Welcome

We are very excited to announce this release of the XRA-31 system!

This version extends capture filtering capabilities to further reduce the size of capture files.
Moreover, all core software components (Debian GNU/Linux, Wireshark) are upgraded to their latest stable upstream versions.

Furthermore this release has several stability and bug fixes.

New since 5.2!

Extended capture filtering with the following new packet types:

• SYNC,
• MAP on reference channel and
• MAP on non-reference channel.

Changelog 5.2.2-1664 (2022-04-05)

Fixes

• [Firmware] Fixed critical issue with OFDMA equalizer that caused considerable packet loss for pilot patterns 1-3 and 8-10.
• [Firmware] Fixed critical bug in downstream SC-QAM phase equalizer that was the source of occasional packet loss.
• [System] Fixed support archives functionality.
• [System] Fixed issue where codeword metadata of downstream SC-QAM packets was sometimes duplicated.
• [System] Improved responsiveness of capture stop action if a large capture file has to be replaced.
• [GUI] Fixed issue with capture button that does not respond after changing capture configuration.

Changelog 5.2-1661 (2021-11-08)

Enhancements

• [System] Upgraded operating system to Debian 11 (bullseye).
• [System] Switched to more versatile network manager.
• [System] Support data disks formatted as XFS for improved performance.
• [Wireshark] Upgraded on-system Wireshark version to v3.4.8.

Fixes

• [System] Improved rolling file switchover performance (also fixes potential data loss for high loads).
• [System] Fixed accuracy and drift issues of duration-based capture/file stop criterion.
• [System] Fixed issue where OFDMA initial and fine ranging bursts are missing if there are multiple initial (respectively station) maintenance grants in a single OFDMA frame.
• [System] Cleanup stale temporary data files at bootup.
• [GUI] Fixed overlay issues leading to hidden scrollbars on wide screens.
• [Firmware] Fixed potential OFDMA data loss if channel center frequency is around 102.4MHz.

Features 

OFDM

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1] 
  • Multiple concurrent data profiles (from A up to P) 
  • Mixed-modulation profiles 
  • Dynamic data profile changes 
  • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix) 
• PLC and NCP demodulation and decoding 
  • Including MER statistics 
  • Timestamp precision is on the order of a few nanoseconds 

OFDMA

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Dynamic UCD changes (including data profile IUC changes) 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1] 
  • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently 
  • Supported pilot patterns: 1-4, 8-11 
  • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 1665 microseconds depending on OFDMA frame size, cyclic prefix and FFT size) 
• Real-time full line rate bandwidth request (REQ) message demodulation and decoding 
  • Timestamp precision is on the order of a few nanoseconds 
• Initial Ranging and Fine Ranging demodulation and decoding 
  • Including MER statistics and time offset estimations 
  • Timestamp precision is on the order of a few nanoseconds

Downstream SC-QAM 

• Real-time demodulation and decoding 
• Full line rate
• Hardware timestamping of packets using reference channel clock (nanosecond resolution) 
• 64/256-QAM, independently configurable per channel 
• Dynamically configurable annex 
  • Annex A (EuroDOCSIS)  
  • Annex B (US DOCSIS)  
    • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported 
    • Viterbi decoding for increased reliability. 
• Extended downstream frequency range support 
  • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1]. 
• Two independent 248 MHz wide receive modules 
  • All channel frequency configurations that can be grouped evenly into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not. 
• Data MER and Reed-Solomon decoder statistics 
• Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

A-TDMA 

• Real-time demodulation and decoding 
• Full line rate
• Full A-TDMA UCD type 29 and 35 support (with the sole exceptions of differential encoding, zero-length preambles and IUC 2 Request_2 demodulation). 
  • All channel bandwidths (from 200 kHz to 6.4 MHz) defined in [CM-SP-PHYv3.0] 
  • All upstream center frequencies allowed by [CM-SP-PHYv3.0] 
  • All modulation types (from QPSK to 64-QAM) defined in [CM-SP-PHYv3.0] 
  • All preamble patterns, types (QPSK0/QSPK1) and lengths from 2 to 1536 bits defined in [CM-SP-PHYv3.0] (Hence, the minimum allowed preamble length is one QPSK symbol) 
  • Scrambler on/off 
  • Fixed/shortened last codeword 
  • All interleaving parameters allowed by [CM-SP-PHYv3.0] 
  • All Reed-Solomon FEC parameters allowed by [CM-SP-PHYv3.0] 
  • Supported IUCs: 1 (Request), 3 (Initial Maintenance), 4 (Station Maintenance), 5 (Short Data Grant), 6 (Long Data Grant), 9 (Advanced PHY Short Data Grant), 10 (Long PHY Short Data Grant), 11 (Advanced PHY Unsollicited Grant) 
  • Dynamic UCD changes 
• Detailed statistics per demodulated burst 
  • Data MER 
  • Time offset 
  • Reed-Solomon decoder statistics 
  • Start minislot ID
    

References 

• [CM-SP-PHYv3.0] DOCSIS^® 3.0 Physical Layer Specification (December 2017, http://www.cablelabs.com/specs/) 
• [CM-SP-PHYv3.1] DOCSIS^® 3.1 Physical Layer Specification (September 2019, http://www.cablelabs.com/specs/) 
• [CM-SP-MULPIv3.1] DOCSIS^® 3.1 MAC and Upper Layer Protocols Interface Specification (September 2019, http://www.cablelabs.com/specs/) 
• [ITU-T Rec J.83] ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution  (December 2007, Telecommunication Standardization Sector of ITU)
  

Known limitations

Firmware

• OFDM

  • Possible temporary data loss during dynamic NCP updates
  • Zero-bit-loading of NCP subcarriers not supported
  • No data MER statistics

• OFDMA

  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• A-TDMA

  • UCD type 2 (DOCSIS 1.x PHY channel and mixed DOCSIS 1.x/2.0 TDMA PHY channel) channels not supported
  • Differential encoding not supported
  • Zero preamble length not supported
  • IUC 2 (Request_2) not supported

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Known Issues

Firmware

• The first channel locking attempt of an OFDM or downstream SC-QAM channel after a system reset or a CMTS change can take considerably longer than subsequent locking attempts. This is because internal frequency offset has to be reliably estimated (after which it is cached).

System and services

• The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
• Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
• Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

 

Welcome

We are very excited to announce this release of the XRA-31 system!

To ease analysis, this version performs real-time resequencing of captured packets (obviating the need for post-reordering steps). In addition, all core software components (Debian GNU/Linux, Wireshark) are upgraded to their latest stable upstream versions.

This release also brings several improvements and bug fixes.

New since 5.1!

Captured packets are now ordered by timestamp.

Changelog 5.1-1652 (2021-02-15) 

Enhancements

• [System] Upgraded operating system to Debian 10 (buster).
• [System] More helpful welcome message of SSH console and login shell.
• [System] Increased overall system robustness by throttling internal logging.
• [System] Clarified software licenses and added XRA-31 EULA.
• [GUI] Added licensing information to help page.
• [GUI] Improved accessibility for visually impaired users.
• [Wireshark] Upgraded on-system Wireshark version to v3.4.2.
• [Firmware] Improved OFDM channel recovery after loss of PLC lock.

Fixes

• [System] Fixed rare bug in timestamp calculation due to imprecise conversions.
• [System] Fixed bogus downstream SC-QAM packet timestamps if reference channel is not locked yet (or is not primary capable).
• [System] Fixed missing codeword info metadata for large US DOCSIS (annex B) downstream SC-QAM MAC frames (up to 2030 bytes).
• [System] Fixed issue where highly-loaded upstream channels fail to relock after a reference SC-QAM loss-of-lock event.
• [System] Fixed possible memory corruption during A-TDMA locking.
• [Wireshark] The absolute timestamp of an upstream MAC frame for segment-header-on service flows is now defined as the timestamp of the last upstream segment needed for reassembly (inverse concatenation and fragmentation).
• [Wireshark] Removed redundant "Reed-Solomon decoding successful" and "LDPC decoding successful" XRA header metadata for SC-QAM packets and OFDMA initial fine/ranging bursts, as uncorrectable packets are never captured to disk anyway.

Features 

OFDM

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1] 
  • Multiple concurrent data profiles (from A up to P) 
  • Mixed-modulation profiles 
  • Dynamic data profile changes 
  • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix) 
• PLC and NCP demodulation and decoding 
  • Including MER statistics 
  • Timestamp precision is on the order of a few nanoseconds 

OFDMA

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Dynamic UCD changes (including data profile IUC changes) 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1] 
  • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently 
  • Supported pilot patterns: 1-4, 8-11 
  • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 1665 microseconds depending on OFDMA frame size, cyclic prefix and FFT size) 
• Real-time full line rate bandwidth request (REQ) message demodulation and decoding 
  • Timestamp precision is on the order of a few nanoseconds 
• Initial Ranging and Fine Ranging demodulation and decoding 
  • Including MER statistics and time offset estimations 
  • Timestamp precision is on the order of a few nanoseconds

Downstream SC-QAM 

• Real-time demodulation and decoding 
• Full line rate
• Hardware timestamping of packets using reference channel clock (nanosecond resolution) 
• 64/256-QAM, independently configurable per channel 
• Dynamically configurable annex 
  • Annex A (EuroDOCSIS)  
  • Annex B (US DOCSIS)  
    • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported 
    • Viterbi decoding for increased reliability. 
• Extended downstream frequency range support 
  • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1]. 
• Two independent 248 MHz wide receive modules 
  • All channel frequency configurations that can be grouped evenly into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not. 
• Data MER and Reed-Solomon decoder statistics 
• Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

A-TDMA 

• Real-time demodulation and decoding 
• Full line rate
• Full A-TDMA UCD type 29 and 35 support (with the sole exceptions of differential encoding, zero-length preambles and IUC 2 Request_2 demodulation). 
  • All channel bandwidths (from 200 kHz to 6.4 MHz) defined in [CM-SP-PHYv3.0] 
  • All upstream center frequencies allowed by [CM-SP-PHYv3.0] 
  • All modulation types (from QPSK to 64-QAM) defined in [CM-SP-PHYv3.0] 
  • All preamble patterns, types (QPSK0/QSPK1) and lengths from 2 to 1536 bits defined in [CM-SP-PHYv3.0] (Hence, the minimum allowed preamble length is one QPSK symbol) 
  • Scrambler on/off 
  • Fixed/shortened last codeword 
  • All interleaving parameters allowed by [CM-SP-PHYv3.0] 
  • All Reed-Solomon FEC parameters allowed by [CM-SP-PHYv3.0] 
  • Supported IUCs: 1 (Request), 3 (Initial Maintenance), 4 (Station Maintenance), 5 (Short Data Grant), 6 (Long Data Grant), 9 (Advanced PHY Short Data Grant), 10 (Long PHY Short Data Grant), 11 (Advanced PHY Unsollicited Grant) 
  • Dynamic UCD changes 
• Detailed statistics per demodulated burst 
  • Data MER 
  • Time offset 
  • Reed-Solomon decoder statistics 
  • Start minislot ID
    

References 

• [CM-SP-PHYv3.0] DOCSIS^® 3.0 Physical Layer Specification (December 2017, http://www.cablelabs.com/specs/) 
• [CM-SP-PHYv3.1] DOCSIS^® 3.1 Physical Layer Specification (September 2019, http://www.cablelabs.com/specs/) 
• [CM-SP-MULPIv3.1] DOCSIS^® 3.1 MAC and Upper Layer Protocols Interface Specification (September 2019, http://www.cablelabs.com/specs/) 
• [ITU-T Rec J.83] ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution  (December 2007, Telecommunication Standardization Sector of ITU)
  

Known limitations

Firmware

• OFDM

  • Possible temporary data loss during dynamic NCP updates
  • Zero-bit-loading of NCP subcarriers not supported
  • No data MER statistics

• OFDMA

  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• A-TDMA

  • UCD type 2 (DOCSIS 1.x PHY channel and mixed DOCSIS 1.x/2.0 TDMA PHY channel) channels not supported
  • Differential encoding not supported
  • Zero preamble length not supported
  • IUC 2 (Request_2) not supported

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Known Issues

Firmware

• The first channel locking attempt of an OFDM or downstream SC-QAM channel after a system reset or a CMTS change can take considerably longer than subsequent locking attempts. This is because internal frequency offset has to be reliably estimated (after which it is cached).

System and services

• The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
• Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
• Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

Welcome 

We are very excited to announce this release of the XRA-31!

This version supports up to 2 OFDM, 2 OFDMA, 32 SC-QAM and 8 A-TDMA channels simultaneously, in real time at line-rate speeds!

Improved OFDM equalization, faster and more robust OFDM locking and significantly reduced power consumption are other notable enhancements.

Furthermore this release has several other improvements and bug fixes.

Check out the details below.

New since 5.0!

• General

  • Lower power consumption.

• OFDM

  • Up to 2 channels.
  • Improved equalization.
  • Improved locking.

• SC-QAM

  • Up to 32 channels.
    

Changelog 5.0.4-1638 (2020-12-07) 

Fixes 

• [Firmware] More robust reset sequence of inter-FPGA serial links (fixes long-standing known issue of occasionally having to reboot after powering on the XRA-31 due to selftest errors).
• [System] Trailing padding is now stripped from upstream MAC frames data bursts without segment header (this also fixes a packet loss issue).
• [System] Fixed issue leading to upstream data burst loss.
• [System] Fixed issue in OFDMA data burst handler to prevent segmentation fault.
• [System] Fixed issue where incomplete support archive could be downloaded.

Changelog 5.0.2-1624 (2020-08-10) 

Fixes 

• [System] Fixed incorrect handling of OFDMA data bursts for SIDs higher than 255 (critical bug introduced in v4.0).
• [Firmware] Don't try to demodulate A-TDMA grants for the NULL SID.

Changelog 5.0-1618 (2020-08-03) 

Enhancements 

• [System] Up to 2 OFDM channels supported.
• [System] Up to 32 SC-QAM channels supported.
• [Firmware] Optimized FPGA power consumption.
• [Firmware] Improved OFDM equalizer leading to significantly higher MER.
  
• [Firmware] Completely revised OFDM locking, faster and more robust than ever, which fixes several locking issues caused by neighboring channel interference.
• [Firmware] More robust OFDM power level estimate (especially during locking).
• [Firmware] Minimized OFDM DC offset.
• [GUI] Added "delete all" button for easier upstream/downstream channel configuration.
• [GUI] Moved channel connector information from configure page to status panel.
• [GUI] Also show PLC-only lock state in status panel.
• [GUI] Multiple layout improvements.
• [GUI/API] Roll-off period is no longer required to configure an OFDM channel.
• [API] Print the client API version without XRA-31 connection.
• [API] Introduced paths (click here for more details).
• [System] Reduced total system update time to about 7 minutes.

Fixes

• [Firmware] Fixed incorrect parsing of MMMs defragmented over multiple PLC MC-MBs, leading to OFDM locking or data demodulation failures.
• [GUI] Fixed missing suffix in status panel OFDM(A) reported input power level.
• [GUI] Fixed OFDM MER reporting for PLC-only lock.
• [GUI] Fixed slow update of status panel after channel configuration change.
• [GUI] Fixed issue where downstream and upstream channels could be edited simultaneously.
• [API] Fixed issue where CLI commands overwrite JSON file with empty file on error.
• [API] Fixed multiple issues related to downloading latest captured file via xra31-analyse.
• [System] Fixed issue with firmware flashing during system update.

Features 

OFDM

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1] 
  • Multiple concurrent data profiles (from A up to P) 
  • Mixed-modulation profiles 
  • Dynamic data profile changes 
  • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix) 
• PLC and NCP demodulation and decoding 
  • Including MER statistics 
  • Timestamp precision is on the order of a few nanoseconds 

OFDMA

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Dynamic UCD changes (including data profile IUC changes) 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1] 
  • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently 
  • Supported pilot patterns: 1-4, 8-11 
  • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 1665 microseconds depending on OFDMA frame size, cyclic prefix and FFT size) 
• Real-time full line rate bandwidth request (REQ) message demodulation and decoding 
  • Timestamp precision is on the order of a few nanoseconds 
• Initial Ranging and Fine Ranging demodulation and decoding 
  • Including MER statistics and time offset estimations 
  • Timestamp precision is on the order of a few nanoseconds

Downstream SC-QAM 

• Real-time demodulation and decoding 
• Full line rate
• Hardware timestamping of packets using reference channel clock (nanosecond resolution) 
• 64/256-QAM, independently configurable per channel 
• Dynamically configurable annex 
  • Annex A (EuroDOCSIS)  
  • Annex B (US DOCSIS)  
    • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported 
    • Viterbi decoding for increased reliability. 
• Extended downstream frequency range support 
  • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1]. 
• Two independent 248 MHz wide receive modules 
  • All channel frequency configurations that can be grouped evenly into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not. 
• Data MER and Reed-Solomon decoder statistics 
• Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

A-TDMA 

• Real-time demodulation and decoding 
• Full line rate
• Full A-TDMA UCD type 29 and 35 support (with the sole exceptions of differential encoding, zero-length preambles and IUC 2 Request_2 demodulation). 
  • All channel bandwidths (from 200 kHz to 6.4 MHz) defined in [CM-SP-PHYv3.0] 
  • All upstream center frequencies allowed by [CM-SP-PHYv3.0] 
  • All modulation types (from QPSK to 64-QAM) defined in [CM-SP-PHYv3.0] 
  • All preamble patterns, types (QPSK0/QSPK1) and lengths from 2 to 1536 bits defined in [CM-SP-PHYv3.0] (Hence, the minimum allowed preamble length is one QPSK symbol) 
  • Scrambler on/off 
  • Fixed/shortened last codeword 
  • All interleaving parameters allowed by [CM-SP-PHYv3.0] 
  • All Reed-Solomon FEC parameters allowed by [CM-SP-PHYv3.0] 
  • Supported IUCs: 1 (Request), 3 (Initial Maintenance), 4 (Station Maintenance), 5 (Short Data Grant), 6 (Long Data Grant), 9 (Advanced PHY Short Data Grant), 10 (Long PHY Short Data Grant), 11 (Advanced PHY Unsollicited Grant) 
  • Dynamic UCD changes 
• Detailed statistics per demodulated burst 
  • Data MER 
  • Time offset 
  • Reed-Solomon decoder statistics 
  • Start minislot ID
    

References 

• [CM-SP-PHYv3.0] DOCSIS^® 3.0 Physical Layer Specification (December 2017, http://www.cablelabs.com/specs/) 
• [CM-SP-PHYv3.1] DOCSIS^® 3.1 Physical Layer Specification (September 2019, http://www.cablelabs.com/specs/) 
• [CM-SP-MULPIv3.1] DOCSIS^® 3.1 MAC and Upper Layer Protocols Interface Specification (September 2019, http://www.cablelabs.com/specs/) 
• [ITU-T Rec J.83] ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution  (December 2007, Telecommunication Standardization Sector of ITU)
  

Known limitations

Firmware

• OFDM

  • Possible temporary data loss during dynamic NCP updates
  • Zero-bit-loading of NCP subcarriers not supported
  • No data MER statistics

• OFDMA

  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• A-TDMA

  • UCD type 2 (DOCSIS 1.x PHY channel and mixed DOCSIS 1.x/2.0 TDMA PHY channel) channels not supported
  • Differential encoding not supported
  • Zero preamble length not supported
  • IUC 2 (Request_2) not supported

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Known Issues

Firmware

• General

  • [Fixed in version 5.0.4] After a system (re)boot, e.g. as part of a system update, it's possible that the inter-FPGA serial links are stuck in a non-operational state. This is signaled in the GUI by error messages on connector US-1. We have taken several measures to improve resilience against this behavior, but are still working on a more pertinent solution. In the meantime, please reset the system via the GUI system page until the serial links are fully operational.

• OFDM

  • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).

System and services

• The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
• Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
• Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

Welcome 

We are very excited to announce this release of the XRA-31!

This is the first release with official Python API/CLI support.
Moreover, the system now supports up to two OFDMA channels.
Faster and more scalable OFDMA locking (with up to hundreds of online CMs) is another notable enhancement.

Furthermore this release has several new enhancements and fixes.

Check out the details below.

New since 4.0!

• API

  • Control the XRA-31 via Python API or CLI commands.
  • Installation is as easy as running pip3 install excentis-xra31.
    
  • Check out https://api.xra31.com for more information.

• OFDMA

  • Up to 2 channels.
    
  • Faster and more scalable locking (with up to hundreds of online CMs).
    

Changelog 4.0-1608 (2020-03-09) 

Enhancements 

• [Firmware] Improved sensitivity of A-TDMA initial ranging burst detector.
• [System] Faster and more scalable (up to hundreds of online CMs) OFDMA locking.
• [System] Reported OFDM(A) channel spectral edges are now devoid of guard bands.
• [System] Support for mounting and accessing removable media via the local file manager.
• [System] Login screen and desktop now have custom XRA-31 background.
• [GUI] Added capabilities section to system page that includes the number of supported channels for each channel type.
• [GUI] Improved look-and-feel of notifications.
• [GUI] Clearer and more detailed channel status messages.
• [GUI] Improved responsivity of "select all" on capture page.
• [GUI] Improved layout of help page.
• [GUI] Improved error handling.
• [Wireshark] Added PLC frequency to all OFDM packet headers (including PLC/NCP).
• [Wireshark] Upgraded on-system version to Wireshark^® 3.0.3-excentis4.

Fixes

• [Firmware] Fixed bug that caused high internal packet loss of a reference SC-QAM channel under certain circumstances, leading to very poor upstream demodulation performance. 
• [Firmware] Fixed unstable automatic gain control for low PAPR (peak to average power ratio) downstream connector input signals (e.g. one single SC-QAM channel), hampering downstream channel locking steps. 
• [Firmware] Fixed bugs in OFDMA frame builder that caused data loss under rare circumstances. 
• [Firmware] Fixed bug where all shortened OFDMA codewords with number of info bits equal to a one plus a multiple of the check matrix lifting factor are dropped. 
• [Firmware] Fixed bugs in OFDMA LDPC decoder that led to decreased error correction performance.
• [System] Fixed bug where OFDMA channel fails to lock after changing upstream channel ID. 
• [System] Fixed incorrect reported time adjust of OFDMA intial and fine  ranging messages if exclusion bands are presents between minislots. 
• [System] Fixed bug in OFDMA initial ranging detector that caused data loss. 
• [System] Fixed initial packet loss on locked OFDMA and A-TDMA channels after a system restart. 
• [System] Fixed bug where timestamps of OFDMA packets are incorrect up to one OFDMA frame duration under certain circumstances. 
• [System] Fixed incorrect upstream packet timestamps around UCD changes under certain circumstances. 
• [System] The system no longer accepts file or directory names longer than 255 characters, which prevents failed captures. 
• [System] Fixed bug in Wicd Network Manager that caused static IP address connection failures.
• [GUI] Also show "folder-up" icon in empty directory. 
• [GUI] Fixed select all icon in case some items are selected (on capture page). 
• [GUI] Fixed several issues related to support archive creation.
• [GUI] Fixed issue with refresh button.

Features 

OFDM

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1] 
  • Multiple concurrent data profiles (from A up to P) 
  • Mixed-modulation profiles 
  • Dynamic data profile changes 
  • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix) 
• PLC and NCP demodulation and decoding 
  • Including MER statistics 
  • Timestamp precision is on the order of a few nanoseconds 

OFDMA

• Real-time demodulation and decoding 
• Full line rate
• All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
• Dynamic UCD changes (including data profile IUC changes) 
• Data demodulation and decoding 
  • All interleaver settings defined by [CM-SP-PHYv3.1] 
  • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1] 
  • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1] 
  • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently 
  • Supported pilot patterns: 1-4, 8-11 
  • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 1665 microseconds depending on OFDMA frame size, cyclic prefix and FFT size) 
• Real-time full line rate bandwidth request (REQ) message demodulation and decoding 
  • Timestamp precision is on the order of a few nanoseconds 
• Initial Ranging and Fine Ranging demodulation and decoding 
  • Including MER statistics and time offset estimations 
  • Timestamp precision is on the order of a few nanoseconds

Downstream SC-QAM 

• Real-time demodulation and decoding 
• Full line rate
• Hardware timestamping of packets using reference channel clock (nanosecond resolution) 
• 64/256-QAM, independently configurable per channel 
• Dynamically configurable annex 
  • Annex A (EuroDOCSIS)  
  • Annex B (US DOCSIS)  
    • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported 
    • Viterbi decoding for increased reliability. 
• Extended downstream frequency range support 
  • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1]. 
• Two independent 248 MHz wide receive modules 
  • All channel frequency configurations that can be grouped into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not. 
• Data MER and Reed-Solomon decoder statistics 
• Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

A-TDMA 

• Real-time demodulation and decoding 
• Full line rate
• Full A-TDMA UCD type 29 and 35 support (with the sole exceptions of differential encoding, zero-length preambles and IUC 2 Request_2 demodulation). 
  • All channel bandwidths (from 200 kHz to 6.4 MHz) defined in [CM-SP-PHYv3.0] 
  • All upstream center frequencies allowed by [CM-SP-PHYv3.0] 
  • All modulation types (from QPSK to 64-QAM) defined in [CM-SP-PHYv3.0] 
  • All preamble patterns, types (QPSK0/QSPK1) and lengths from 2 to 1536 bits defined in [CM-SP-PHYv3.0] (Hence, the minimum allowed preamble length is one QPSK symbol) 
  • Scrambler on/off 
  • Fixed/shortened last codeword 
  • All interleaving parameters allowed by [CM-SP-PHYv3.0] 
  • All Reed-Solomon FEC parameters allowed by [CM-SP-PHYv3.0] 
  • Supported IUCs: 1 (Request), 3 (Initial Maintenance), 4 (Station Maintenance), 5 (Short Data Grant), 6 (Long Data Grant), 9 (Advanced PHY Short Data Grant), 10 (Long PHY Short Data Grant), 11 (Advanced PHY Unsollicited Grant) 
  • Dynamic UCD changes 
• Detailed statistics per demodulated burst 
  • Data MER 
  • Time offset 
  • Reed-Solomon decoder statistics 
  • Start minislot ID
    

References 

• [CM-SP-PHYv3.0] DOCSIS^® 3.0 Physical Layer Specification (December 2017, http://www.cablelabs.com/specs/) 
• [CM-SP-PHYv3.1] DOCSIS^® 3.1 Physical Layer Specification (September 2019, http://www.cablelabs.com/specs/) 
• [CM-SP-MULPIv3.1] DOCSIS^® 3.1 MAC and Upper Layer Protocols Interface Specification (September 2019, http://www.cablelabs.com/specs/) 
• [ITU-T Rec J.83] ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution  (December 2007, Telecommunication Standardization Sector of ITU)
  

Known limitations

Firmware

• OFDM

  • Possible temporary data loss during dynamic NCP updates
  • Zero-bit-loading of NCP subcarriers not supported
  • No data MER statistics

• OFDMA

  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• A-TDMA

  • UCD type 2 (DOCSIS 1.x PHY channel and mixed DOCSIS 1.x/2.0 TDMA PHY channel) channels not supported
  • Differential encoding not supported
  • Zero preamble length not supported
  • IUC 2 (Request_2) not supported

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Known Issues

Firmware

• General

  • After a system (re)boot, e.g. as part of a system update, it's possible that the inter-FPGA serial links are stuck in a non-operational state. This is signaled in the GUI by error messages on connector US-1. We have taken several measures to improve resilience against this behavior, but are still working on a more pertinent solution. In the meantime, please reset the system via the GUI system page until the serial links are fully operational.

• OFDM

  • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).
    
    This effect is considerable on small-bandwidth OFDM channels. Depending on PLC frequency and FFT size, initial locking of a 24 MHz channel (the minimum allowed per [CM-SP-PHYv3.1]) can take up to 10 minutes. Subsequent re-locking steps, even on different channels, should be on the order of seconds. A workaround is to first 'pre-lock' the XRA-31 on a dummy 192 MHz channel (which should take no longer than 1 minute), remove this channel and re-add the 24 MHz channel.

System and services

• The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
• Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
• Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

Welcome 

We are very excited to announce this release of the XRA-31 system! 

The system now supports the use of a downstream SC-QAM channel as reference.
This makes it possible to capture upstream traffic (both A-TDMA and OFDMA) in absence of an OFDM channel, extending the debugging capabilities of  the XRA-31 to an even wider range of DOCSIS 3.0/3.1 setups. 

Moreover, the new "rolling file capture" functionality allows you to capture continuously to a ring buffer of files (without being limited by disk capacity).
This makes it possible to analyze rare events effectively. 

Furthermore this release has several new improvements and bug fixes. 

Check out the details below. 

Features 

• New since 3.1! 

  • Reference Downstream SC-QAM 

    • Select a downstream SC-QAM channel as timing reference and source for upstream demodulation 
    • Fully flexible 
      • Choose any configured SC-QAM channel as reference 
      • Both OFDMA/A-TDMA supported 
      • Can be combined with other OFDM channels 

  • Rolling File Capture 

    • Capture to a ring buffer of files 
    • File stop criterion based on duration or size 

• OFDM

  • Real-time demodulation and decoding 
  • Full line rate (up to approx. 2 Gbps per channel)
  • All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
  • Data demodulation and decoding 
    • All interleaver settings defined by [CM-SP-PHYv3.1] 
    • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1] 
    • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1] 
    • Multiple concurrent data profiles (from A up to P) 
    • Mixed-modulation profiles 
    • Dynamic data profile changes 
    • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix) 
  • PLC and NCP demodulation and decoding 
    • Including MER statistics 
    • Timestamp precision is on the order of a few nanoseconds 

• OFDMA
  

  • Real-time demodulation and decoding 
  • Full line rate (up to approx. 1 Gbps per channel)
  • All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1] 
  • Dynamic UCD changes (including data profile IUC changes) 
  • Data demodulation and decoding 
    • All interleaver settings defined by [CM-SP-PHYv3.1] 
    • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1] 
    • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1] 
    • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently 
    • Supported pilot patterns: 1-4, 8-11 
    • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 1665 microseconds depending on OFDMA frame size, cyclic prefix and FFT size) 
  • Real-time full line rate bandwidth request (REQ) message demodulation and decoding 
    • Timestamp precision is on the order of a few nanoseconds 
  • Initial Ranging and Fine Ranging demodulation and decoding 
    • Including MER statistics and time offset estimations 
    • Timestamp precision is on the order of a few nanoseconds

• Downstream SC-QAM 

  • Real-time demodulation and decoding 
  • Full line rate (up to approx. 1.2 Gbps combined) 
  • 24 independent channels supported 
  • Hardware timestamping of packets using reference channel clock (nanosecond resolution) 
  • 64/256-QAM, independently configurable per channel 
  • Dynamically configurable annex 
    • Annex A (EuroDOCSIS)  
    • Annex B (US DOCSIS)  
      • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported 
      • Viterbi decoding for increased reliability. 
  • Extended downstream frequency range support 
    • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1]. 
  • Two independent 248 MHz wide receive modules 
    • All channel frequency configurations that can be grouped into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not. 
  • Data MER and Reed-Solomon decoder statistics 
  • Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

• A-TDMA 

  • Real-time demodulation and decoding 
  • Full line rate (up to approx. 240 Mbps combined) 
  • 8 independent channels supported 
  • Full A-TDMA UCD type 29 and 35 support (with the sole exceptions of differential encoding, zero-length preambles and IUC 2 Request_2 demodulation). 
    • All channel bandwidths (from 200 kHz to 6.4 MHz) defined in [CM-SP-PHYv3.0] 
    • All upstream center frequencies allowed by [CM-SP-PHYv3.0] 
    • All modulation types (from QPSK to 64-QAM) defined in [CM-SP-PHYv3.0] 
    • All preamble patterns, types (QPSK0/QSPK1) and lengths from 2 to 1536 bits defined in [CM-SP-PHYv3.0] (Hence, the minimum allowed preamble length is one QPSK symbol) 
    • Scrambler on/off 
    • Fixed/shortened last codeword 
    • All interleaving parameters allowed by [CM-SP-PHYv3.0] 
    • All Reed-Solomon FEC parameters allowed by [CM-SP-PHYv3.0] 
    • Supported IUCs: 1 (Request), 3 (Initial Maintenance), 4 (Station Maintenance), 5 (Short Data Grant), 6 (Long Data Grant), 9 (Advanced PHY Short Data Grant), 10 (Long PHY Short Data Grant), 11 (Advanced PHY Unsollicited Grant) 
    • Dynamic UCD changes 
  • Detailed statistics per demodulated burst 
    • Data MER 
    • Time offset 
    • Reed-Solomon decoder statistics 
    • Start minislot ID
      

References 

• [CM-SP-PHYv3.0]      DOCSIS 3.0 Physical Layer Specification (version I13 or later; http://www.cablelabs.com/specs/) 
• [CM-SP-PHYv3.1]      DOCSIS 3.1 Physical Layer Specification (version I13 or later; http://www.cablelabs.com/specs/) 
• [CM-SP-MULPIv3.1]   DOCSIS 3.1 MAC and Upper Layer Protocols Interface Specification (version I14 or later; http://www.cablelabs.com/specs/) 
• [ITU-T Rec J.83] ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution  (December 2007, Telecommunication Standardization Sector of ITU)
  

Known limitations

Firmware

• OFDM

  • Limited to one supported channel receiver
  • Possible temporary data loss during dynamic NCP updates
  • Zero-bit-loading of NCP subcarriers not supported
  • No data MER statistics

• OFDMA

  • Limited to one supported channel receiver
  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• SC-QAM

  • Limited to 24 supported channel receivers

• A-TDMA

  • Limited to 8 supported channel receivers
  • UCD type 2 (DOCSIS 1.x PHY channel and mixed DOCSIS 1.x/2.0 TDMA PHY channel) channels not supported
  • Differential encoding not supported
  • Zero preamble length not supported
  • IUC 2 (Request_2) not supported

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Changelog 3.1-1600 (2019-11-05) 

Improvements  

• WebAdmin (GUI)

  • Improved capture and channel status reporting in status panel.
  • The configure page now stays in edit mode after an authentication failure. 
  • The capture page is now also continuously updated in read-only mode. 
  • Consistently use 1024 (instead of 1000) for all byte-related calculations and reported file sizes and capture rates, in line with the convention used in most operating systems.
    

Bugfixes 

• Firmware

  • Fixed critical bug in embedded software that prevented downstream SC-QAM annex B channels from locking under certain circumstances.

• Systems and services 

  • Fixed critical bug in OFDM codeword stream processor that resulted in daemon crash. 
  • Reject full access mode request if firmware feature level is unsupported. 
  • Fixed several race conditions. 

• WebAdmin (GUI) 

  • Copy-down modulation button for downstream SC-QAM configuration now properly copies the value to the rows below (and not to all rows). 
  • Fixed incorrect display of capture start/stop button in some conditions.

Known Issues

• Firmware

  • General

    • After a system (re)boot, e.g. as part of a system update, it's possible that the inter-FPGA serial links are stuck in a non-operational state. This is signaled in the GUI by error messages on connector US-1. We have taken several measures to improve resilience against this behavior, but are still working on a more pertinent solution. In the meantime, please reset the system via the GUI system page until the serial links are fully operational.

  • OFDM

    • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).
      
      This effect is considerable on small-bandwidth OFDM channels. Depending on PLC frequency and FFT size, initial locking of a 24 MHz channel (the minimum allowed per [CM-SP-PHYv3.1]) can take up to 10 minutes. Subsequent re-locking steps, even on different channels, should be on the order of seconds. A workaround is to first 'pre-lock' the XRA-31 on a dummy 192 MHz channel (which should take no longer than 1 minute), remove this channel and re-add the 24 MHz channel.

• System and services

  • The system accepts file names longer than 255 characters and starts capturing, but storing the file fails in this case.
  • The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
  • Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
  • Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

• WebAdmin (GUI)

  • Once a support archive is created, the UI framework sometimes start creating multiple archives in a loop. Other system tasks (for example system reset) might take a long time until they are performed.
    As a workaround the user can use the power button on the system to restart the system. Press once shortly to start shutting down the system properly. Once shut down, press the power button again to start the system again.
  • Layout on small displays can be improved.

Welcome

We are very excited to announce the third major release of the XRA-31 system!

The system can now capture upstream A-TDMA (full UCD type 29 and 35 support).
This means you can capture up to 1 OFDM channel, 1 OFDMA channel, 24 downstream SC-QAM and 8 A-TDMA channels simultaneously and synchronously with nanosecond resolution, as all packets are hardware timestamped using the same reference OFDM channel clock!

Furthermore this release has several new features, improvements and bug fixes.

Check out the details below.

Features

• New since 3.0!

  • Upstream A-TDMA

    • See details below!

  • Continuous upstream locking

    • Added continuous synchronization of upstream channels with downstream channels.
    • Added continuous automatic gain control adjustments for upstream channels.

  • WebAdmin (GUI) user experience improvements

    • Better defaults and button locations to allow faster configuration editing.
    • Where applicable, the status panel now also shows channel ID and frequency.
    • Improved file system navigation.

• OFDM

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 2 Gbps per channel)
  • Hardware timestamping of packets using channel clock (nanosecond resolution)
  • All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1]
  • Data demodulation and decoding
    • All interleaver settings defined by [CM-SP-PHYv3.1]
    • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1]
    • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1]
    • Multiple concurrent data profiles (from A up to P)
    • Mixed-modulation profiles
    • Dynamic data profile changes
    • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix)
  • PLC and NCP demodulation and decoding
    • Including MER statistics
    • Timestamp precision is on the order of a few nanoseconds

• OFDMA

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 1 Gbps per channel)
  • Hardware timestamping of packets using reference OFDM channel clock (nanosecond resolution)
  • All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1]
  • Dynamic UCD changes (including data profile IUC changes)
  • Data demodulation and decoding
    • All interleaver settings defined by [CM-SP-PHYv3.1]
    • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1]
    • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1]
    • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently
    • Supported pilot patterns: 1-4, 8-11
    • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 945 microseconds depending on OFDMA frame size)
  • Real-time full line rate bandwidth request (REQ) message demodulation
    • Timestamp precision is on the order of a few nanoseconds
  • Initial Ranging and Fine Ranging demodulation and decoding
    • Including MER statistics and time offset estimations
    • Timestamp precision is on the order of a few nanoseconds

• SC-QAM

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 1.2 Gbps combined)
  • 24 independent channels supported
  • Hardware timestamping of packets using reference OFDM channel clock (nanosecond resolution)
  • 64/256-QAM, independently configurable per channel
  • Dynamically configurable annex
    • Annex A (EuroDOCSIS)
    • Annex B (US DOCSIS)
      • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported
      • Viterbi decoding for increased reliability.
  • Extended downstream frequency range support
    • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1].
  • Two independent 248 MHz wide receive modules
    • All channel frequency configurations that can be grouped into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not.
  • Data MER and Reed-Solomon decoder statistics
  • Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

• A-TDMA

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 240 Mbps combined)
  • 8 independent channels supported
  • Hardware timestamping of packets using reference OFDM channel clock (nanosecond resolution)
  • Full A-TDMA UCD type 29 and 35 support (with the sole exceptions of differential encoding, zero-length preambles and IUC 2 Request_2 demodulation).
    • All channel bandwidths (from 200 kHz to 6.4 MHz) defined in [CM-SP-PHYv3.0]
    • All upstream center frequencies allowed by [CM-SP-PHYv3.0]
    • All modulation types (from QPSK to 64-QAM) defined in [CM-SP-PHYv3.0]
    • All preamble patterns, types (QPSK0/QSPK1) and lengths from 2 to 1536 bits defined in [CM-SP-PHYv3.0] (Hence, the minimum allowed preamble length is one QPSK symbol)
    • Scrambler on/off
    • Fixed/shortened last codeword
    • All interleaving parameters allowed by [CM-SP-PHYv3.0]
    • All Reed-Solomon FEC parameters allowed by [CM-SP-PHYv3.0]
    • Supported IUCs: 1 (Request), 3 (Initial Maintenance), 4 (Station Maintenance), 5 (Short Data Grant), 6 (Long Data Grant), 9 (Advanced PHY Short Data Grant), 10 (Long PHY Short Data Grant), 11 (Advanced PHY Unsollicited Grant)
    • Dynamic UCD changes
  • Detailed statistics per demodulated burst
    • Data MER
    • Time offset
    • Reed-Solomon decoder statistics
    • Start minislot ID

References

• [CM-SP-PHYv3.0]      DOCSIS 3.0 Physical Layer Specification (version I13 or later; http://www.cablelabs.com/specs/)
• [CM-SP-PHYv3.1]      DOCSIS 3.1 Physical Layer Specification (version I13 or later; http://www.cablelabs.com/specs/)
• [CM-SP-MULPIv3.1]   DOCSIS 3.1 MAC and Upper Layer Protocols Interface Specification (version I14 or later; http://www.cablelabs.com/specs/)
• [ITU-T Rec J.83]         ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution (December 2007, Telecommunication Standardization Sector of ITU)

Known limitations

Firmware

• OFDM

  • Limited to one supported channel receiver
  • Possible temporary data loss during dynamic NCP updates
  • Zero-bit-loading of NCP subcarriers not supported
  • No data MER statistics

• OFDMA

  • Limited to one supported channel receiver
  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• SC-QAM

  • Limited to 24 supported channel receivers

• A-TDMA

  • Limited to 8 supported channel receivers
  • UCD type 2 (DOCSIS 1.x PHY channel and mixed DOCSIS 1.x/2.0 TDMA PHY channel) channels not supported
  • Differential encoding not supported
  • Zero preamble length not supported
  • IUC 2 (Request_2) not supported

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Changelog 3.0.2-944 (2019-08-08)

Improvements

• System and services

  • Better thermal management.
    • XRA-31 temperature sensor information is now available via standard Linux Hardware Monitoring interface; User-space application: sensors
    • FPGA will be shut down when we cannot ensure correct behavior (especially regarding timing)
  • Device Driver: Add FPGA firmware and state checks.
    • FPGA firmware and driver version check, feature verification; using FPGA feature level.
    • Device state verification: Do not allow to access the device when it has been shut down or restarted.
  • General: Improved FPGA firmware and driver version and feature verification.
  • Control Daemon: Improved exception handling to avoid improper exit due to FPGA thermal shutdown (or restart).
  • Avoid or remove unnecessary mutex locks.
  • Control Daemon: Improved logging.
    • Decreased debug logging.
    • Rate limit on error logging.
  • Control Daemon: small speed-up when configuring downstream SC-QAM channels.
  • Control Daemon: Avoid inconsistent processing state: No longer allow to configure more than one Upstream Channel Receiver with the same US Channel ID.
  • Firmware tool: Better exception handling related to device driver / firmware control.
  • XRA-31 self-test: Better exception handling related to device driver / firmware control.

Bugfixes

• Firmware

  • General

    • Fixed suboptimal placement of PCIe clock manager.
    • Fixed several unsafe clock domain crossings.
    • Fixed several place-and-route warnings.

  • OFDM

    • Fixed bugs in MMM processor where packets were incorrectly dropped if a codeword contains 3 info bytes or if the MAC header is fragmented over multiple codewords.
    • Fixed bug in codeword builder which led to packet loss in case a NULL NCP-MB is the only data NCP-MB in an OFDM symbol.

  • SC-QAM

    • Fixed improper reset of hardware blocks after disabling downstream SC-QAM channel receiver. This reduces power consumption considerably.
    • Fixed spurious output valid signal of deinterleaver after reset or FEC frame sync loss.

• Systems and services

  • Fix XRA TLV length of IUC for ranging packets in pcap output files (xra.tlv.iuc field in Wireshark).
  • Fixed possible multi-thread access issues with pcap file save.
  • Fix reset of US Channel ID/SID mapping state for all upstreams when the configuration of a single upstream channel receiver changed.
  • Device driver: Fixed possibly uninitialized DMA registers.

• WebAdmin (GUI)

  • Fixed incorrect display of OFDMA frequency range.

Known Issues

• Firmware

  • General

    • After a system (re)boot, e.g. as part of a system update, it's possible that the inter-FPGA serial links are stuck in a non-operational state. This is signaled in the GUI by error messages on connector US-1. We have taken several measures to improve resilience against this behavior, but are still working on a more pertinent solution. In the meantime, please reset the system via the GUI system page until the serial links are fully operational.

  • OFDM

    • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).
      
      This effect is considerable on small-bandwidth OFDM channels. Depending on PLC frequency and FFT size, initial locking of a 24 MHz channel (the minimum allowed per [CM-SP-PHYv3.1]) can take up to 10 minutes. Subsequent re-locking steps, even on different channels, should be on the order of seconds. A workaround is to first 'pre-lock' the XRA-31 on a dummy 192 MHz channel (which should take no longer than 1 minute), remove this channel and re-add the 24 MHz channel.

• System and services

  • The system accepts file names longer than 255 characters and starts capturing, but storing the file fails in this case.
  • The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
  • Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
  • Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

• WebAdmin (GUI)

  • Once a support archive is created, the UI framework sometimes start creating multiple archives in a loop. Other system tasks (for example system reset) might take a long time until they are performed.
    As a workaround the user can use the power button on the system to restart the system. Press once shortly to start shutting down the system properly. Once shut down, press the power button again to start the system again.
  • Layout on small displays can be improved.

Changelog 3.0-795 (2019-06-11)

Improvements

• Firmware

  • OFDM

    • Channel receivers are now disabled on FPGA after removal of the corresponding OFDM(A) channels, which reduces power consumption considerably. This has no considerable impact on subsequent locking time.
    • Dynamic NCP updates are now supported but might still lead to temporary data loss.

  • OFDMA

    • Channel receivers are now disabled on FPGA after removal of the corresponding OFDM(A) channels, which reduces power consumption considerably. This has no considerable impact on subsequent locking time.

  • SC-QAM

    • Improved channel equalization of EuroDOCSIS (annex A) SC-QAM channels.

  • A-TDMA

    • Added upstream A-TDMA support

• System and services

  • Time and power offset of all locked upstream channels (including OFDMA) is now continuously tracked and updated. This ensures that the XRA-31 dynamically adapts to RF network changes or drift over long time periods. Note that the internal time offset corrections are rather conservative, allowing reliable troubleshooting of time offset CM/CMTS issues via the Wireshark XRA header of upstream data bursts.
  • More efficient processing of highly-loaded OFDM profiles with high fraction of uncorrectables.
  • Better handling of upstream segments which only contain stuff bytes.
  • The XRA-31 Control Daemon no longer exits when the FPGA firmware is not supported.
  • The Control Daemon no longer allows to change the configuration (enter full access mode) if hardware errors have been detected.
  • IUC is now also included in the XRA header of OFDMA initial and fine ranging packets. This allows easier filtering.

• WebAdmin (GUI)

  • Reviewed Channel configuration
    • US/EURO slider (for changing downstream SC-QAM annex) is moved to edit mode of the downstream channels.
    • Downstream SC-QAM channels now use 256-QAM by default instead of 64-QAM.
    • You can now sort on the channel name.
    • The upstream (OFDMA/A-TDMA) add-button is also disabled when there are no more detected upstream channels available.
  • Status information
    • XRA-31 self-test errors are now shown as system errors on the Connectors.
    • The GUI properly reports invalid firmware state to the user via the Connector state. This can happen for example when an update of the firmware has failed.
    • Rounding start/stop frequencies for OFDM(A) channels to MHz boundary if possible.
    • Where applicable, channel ID and frequency are also shown in channel name.
    • Capture stop reason is now also shown in the Capture status information.
    • Replaced confusing '-' separator in expanded view. Now using a dot-symbol to avoid incorrectly interpreting the values as negative values.
  • System page
    • Added confirmation window before resetting the system.
    • Do not allow to create multiple support archives at once.
      • All system administration related tasks show a notice and/or are disabled when a support archive is being created. The latter can take a long time and since the system administration tasks are run sequentially, the user might be waiting for a long time without any notification otherwise.
  • File system navigation
    • Added missing leading '/' when showing absolute file system paths on the server.
    • Added "select all" / "select none" button.
    • Add "directory up" links where file system navigation is possible.
    • Files are ordered by date by default.

• Wireshark

  • Updated base to the official Wireshark 2.6.8 version.

Bugfixes

• Firmware

  • Declare OFDMA channel as unlocked after lock on downstream reference clock is lost.

• System and services

  • Fixed several bugs related to incorrect timestamps of captured downstream SC-QAM packets in case no OFDM channel is present.
  • Fixed invalid creation of non-existing upstream Channel ID 0 and/or 255 in certain situations.
  • Fixed segmentation fault occurring in rare circumstances.
  • Fixed recovery when MAC stream loses lock.
  • Fixed race condition in OCD processing.
  • Fixed incorrect reporting of "Reed-Solomon Decoding Successful" (xra.tlv.cw_info.rs_decoding_successful) in XRA header in capture file.

• WebAdmin (GUI)

  • Fixed issue where WebAdmin tries to add multiple filters and/or file outputs to a Capture.
  • Fixed issues with multi-user access.
  • Fixed some graphical issues when scaling the UI.
  • Fixed issue deleting files with ',' in their name.

Known Issues

• Firmware

  • General

    • After a system (re)boot, e.g. as part of a system update, it's possible that the inter-FPGA serial links are stuck in a non-operational state. This is signaled in the GUI by error messages on connector US-1. We have taken several measures to improve resilience against this behavior, but are still working on a more pertinent solution.
      In the meantime, please reset the system via the GUI system page until the serial links are fully operational.

  • OFDM

    • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).
      
      This effect is considerable on small-bandwidth OFDM channels. Depending on PLC frequency and FFT size, initial locking of a 24 MHz channel (the minimum allowed per [CM-SP-PHYv3.1]) can take up to 10 minutes. Subsequent re-locking steps, even on different channels, should be on the order of seconds. A workaround is to first 'pre-lock' the XRA-31 on a dummy 192 MHz channel (which should take no longer than 1 minute), remove this channel and re-add the 24 MHz channel.

• System and services

  • The system accepts file names longer than 255 characters and starts capturing, but storing the file fails in this case.
  • The reported upstream channel MER is the average over all fine ranging requests (for OFDMA) or all data bursts excluding initial ranging requests and bandwidth requests (for A-TDMA) over an elapsed interval of at most 30s. As such, it is possible that N/A (not available) is shown on low-load channels with T4 timeout multiplier higher than 1.
  • Captured Wireshark traces might contain invalid (malformed) packets corresponding to collisions (or possible RF interference) on A-TDMA IUC 1 (bandwidth request) grants. In a future release we plan to filter out these spurious bursts.
  • Inverse upstream Concatenation and Fragmentation (ICCF) of "segment header on" service flows is now performed for each channel independently. Hence, for CMs in MTCM (multi transmit channel mode), MAC frames that are fragmented over multiple upstream channels are not detected and consequently absent in the Wireshark trace. A future release will support ICCF over multiple channels.

• WebAdmin (GUI)

  • Once a support archive is created, the UI framework sometimes start creating multiple archives in a loop. Other system tasks (for example system reset) might take a long time until they are performed.
    As a workaround the user can use the power button on the system to restart the system. Press once shortly to start shutting down the system properly. Once shut down, press the power button again to start the system again.
  • Layout on small displays can be improved.

Welcome

We are very excited to announce the second major release of the XRA-31 system!

The system can now capture downstream SC-QAM (annex A/B, 64/256-QAM are supported, full spectrum).
This means you can capture up to 1 OFDM channel, 1 OFDMA channel and 24 downstream SC-QAM channels simultaneously and synchronously with nanosecond resolution, as all packets are hardware timestamped using the same reference OFDM channel clock!

Furthermore this release has several new features, improvements and bug fixes.

Check out the details below.

Features

• New since 2.0!

  • Downstream SC-QAM

    • See details below!

  • OFDMA bandwidth requests

    • The system can now capture OFDMA bandwidth request (REQ) messages.

  • Revised capture filtering

    • Capture Filtering has been revised to incorporate SC-QAM support

  • WebAdmin (GUI) re-design

    • Updated Channel Configuration
      • All Downstream Channels are now edited at once.
      • All Upstream Channels are now edited at once.
    • Updated Capture Configuration
    • New Status Panel
      
      • Collapsible panel
      • Status icon and detail message box show more extended information on the status including suggestions for changes on physical setup.
      • Physical Connector status information is now separated from the DOCSIS Channel status information.
    • Ease-of-use
      
      • Add "copy-down" and "copy-down with value increment"
      • Sorting in all relevant table columns
      • Context help is now always available via the help button in the navigation panel

• OFDM

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 2 Gbps per channel)
  • Hardware timestamping of packets using channel clock (nanosecond resolution)
  • All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1]
  • Data demodulation and decoding
    • All interleaver settings defined by [CM-SP-PHYv3.1]
    • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1]
    • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1]
    • Multiple concurrent data profiles (from A up to P)
    • Mixed-modulation profiles
    • Dynamic data profile changes
    • Timestamp precision of DOCSIS frames is equal to one OFDM symbol (between 21 and 45 microseconds depending on FFT size and cyclic prefix)
  • PLC and NCP demodulation and decoding
    • Including MER statistics
    • Timestamp precision is on the order of a few nanoseconds

• OFDMA

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 1 Gbps per channel)
  • Hardware timestamping of packets using reference OFDM channel clock (nanosecond resolution)
  • All FFT sizes, cyclic prefixes and roll-off periods defined by [CM-SP-PHYv3.1]
  • Dynamic UCD changes (including data profile IUC changes)
  • Data demodulation and decoding
    • All interleaver settings defined by [CM-SP-PHYv3.1]
    • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1]
    • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1]
    • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently
    • Supported pilot patterns: 1-4, 8-11
    • Timestamp precision of DOCSIS frames is equal to one OFDMA frame (between 126 and 945 microseconds depending on OFDMA frame size)
  • Real-time full line rate bandwidth request (REQ) message demodulation - NEW since v2.0!
    • Timestamp precision is on the order of a few nanoseconds
  • Initial Ranging and Fine Ranging demodulation and decoding
    • Including MER statistics and time offset estimations
    • Timestamp precision is on the order of a few nanoseconds

• SC-QAM

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 1.2 Gbps combined)
  • 24 independent channels supported
  • Hardware timestamping of packets using reference OFDM channel clock (nanosecond resolution)
  • 64/256-QAM, independently configurable per channel
  • Dynamically configurable annex
    • Annex A (EuroDOCSIS)
    • Annex B (US DOCSIS)
      • All interleaving parameters (control words) defined in [ITU-T Rec. J.83] supported
      • Viterbi decoding for increased reliability.
  • Extended downstream frequency range support
    • Channel frequencies can be any multiple of 62.5 kHz between 108 and 1006 MHz, complying with all CM requirements in [CM-SP-PHYv3.1].
  • Two independent 248 MHz wide receive modules
    • All channel frequency configurations that can be grouped into the two receive module bands are valid, e.g. a channel configuration consisting of three channels at 200 MHz, 440 MHz and 1000 MHz is valid, but a configuration with frequencies 200 MHz, 600 MHz and 1000 MHz is not.
  • Data MER and Reed-Solomon decoder statistics
  • Timestamp precision of DOCSIS frames is equal to one MPEG frame (between 29 and 56 microseconds depending on annex and modulation)

References

• [CM-SP-PHYv3.1]      DOCSIS 3.1 Physical Layer Specification (version I13 or any later version; http://www.cablelabs.com/specs/)
• [CM-SP-MULPIv3.1]   DOCSIS 3.1 MAC and Upper Layer Protocols Interface Specification (version I14 or any later version; http://www.cablelabs.com/specs/)
• [ITU-T Rec J.83]         ITU-T J.83: Digital multi-programme systems for television, sound and data services for cable distribution (December 2007, Telecommunication Standardization Sector of ITU)

Known limitations

Firmware

• OFDM

  • Limited to one supported channel receiver
  • No dynamic NCP profile changes
  • No data MER statistics

• OFDMA

  • Limited to one supported channel receiver
  • Unsupported pilot patterns: 5-7, 12-14
  • No probing sequences
  • No data MER statistics

• SC-QAM

  • Limited to 24 supported channel receivers

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Changelog 2.0.2-442 (2018-02-27)

Improvements

• Firmware

  • Improved resilience to known issue (described hereafter) where serial links are stuck in a non-operational state after a system (re)boot.

• System and services

  • Hardware self-test failure information is now available through the Connectors status in the WebAdmin GUI.

• Wireshark

  • Update to Wireshark 2.6.5

Bugfixes

• Firmware

  • Fixed bug where an OFDM channel is stuck in "PLC-only lock" if extended headers are present in PLC MC MMMs.
  • Fixed bug where messages of low-bandwidth streams (such as OFDMA REQ messages on low-load channels) are not visible in the capture file by upper bounding the latency of the internal FPGA streams to a fraction of a second.

• System and services

  • Fixed bug where an encrypted REG-REQ-MP is dropped and not saved to the capture file.
  • Fixed bug where OFDMA REQ messages are dropped in some cases.
  • Fixed bug where, in some cases, the Annex is not set correctly in the XRA header.
  • Fixed possible out-of-bounds memory access in MER calculation.
  • Fixed race condition.

Known Issues

• Firmware

  • General

    • After a system (re)boot, e.g. as part of a system update, it's possible that the inter-FPGA serial links are stuck in a non-operational state. This is signaled in the GUI by error messages on connector US-1. We have taken several measures to improve resilience against this behavior, but are still working on a more pertinent solution. In the meantime, please reset the system via the GUI system page until the serial links are fully operational.

  • OFDM

    • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).
      
      This effect is considerable on small-bandwidth OFDM channels. Depending on PLC frequency and FFT size, initial locking of a 24 MHz channel (the minimum allowed per [CM-SP-PHYv3.1]) can take up to 10 minutes. Subsequent re-locking steps, even on different channels, should be on the order of seconds. A workaround is to first 'pre-lock' the XRA-31 on a dummy 192 MHz channel (which should take no longer than 1 minute), remove this channel and re-add the 24 MHz channel.

  • SC-QAM

    • MER can be significantly lower on annex A channels with low traffic load on some CMTSs. This is due to poor symbol scrambling (needed to maintain proper lock) caused by sub-optimal low-entropy payload sequences of null packets. A workaround is to generate some (possibly artificial) traffic on the affected channels.

• System and services

  • During the OFDMA locking phase, the XRA-31 estimates the optimal time and power offset for demodulation (comparable to the ranging process of a cable modem). After RF network changes, primary OFDM or OFDMA channel configuration changes, or due to drift over long time periods, these estimations can deviate considerably from their initial value, leading to demodulation failures for data bursts. In a future release, the XRA-31 will continuously track and update time and power offset after locking.
    
    In the meantime, as a workaround for the above described cases, please remove and re-add the OFDMA channel to force a new locking phase. Note that you can keep track of the XRA-31 internal time offset by inspecting the Wireshark XRA header of the fine ranging signals.
  • The system accepts file names longer than 255 characters and starts capturing, but storing the file fails in this case.

• WebAdmin (GUI)

  • Multi-user access shows incomplete or invalid status information.
    • This is seen when connecting with multiple users (or browser tabs) to the WebAdmin.
    • Also unexpected error messages may be shown.
  • The XRA-31 Control Daemon exits when the FPGA firmware is not supported. The GUI has no way to properly show this state to the user and the user is just prompted with an error that connection to the XRA-31 server failed. This can happen for example when an update of the firmware failed. The user can detect this state by verifying that the firmware versions on the System page do not match.
  • Layout on small displays can be improved.

Changelog 2.0-138 (2018-11-12)

Improvements

• General

  • Add downstream SC-QAM support
  • Physical Connector status information is now separated from the DOCSIS Channel status information.

• Firmware

  • OFDM

    • Improved channel locking (between 2 and 30 times faster)
    • Improved automatic gain control
    • Optimized digital dynamic range
    • Improved anti-aliasing filter characteristics

  • OFDMA

    • Added bandwidth request processor
    • Improved initial ranging processor
    • Optimized digital dynamic range
    • Improved anti-aliasing filter characteristics

  • SC-QAM

    • Added downstream SC-QAM support

• System and services

  • Slightly improved capture performance
  • Performing CRC/HCS checks on incoming packets
  • Improved RPC/user input validation and error handling
  • Fixed some typos in error messages
  • The system now supports multiple captures with their own channel selection, filter criteria and file output. The GUI allows to use a single capture with a single filter and file output configuration.

• WebAdmin (GUI)

  • General re-design and improvements in Channel Configuration, Capture Configuration and Status Panel.
  • The Status Panel now also shows the capture duration.
  • The system now also provides informational messages regarding the Physical Connector and Channel in the Status Panel.
  • Context help
    • All help is now in one page. The help button jumps to the right section based on the last context used in the GUI.
    • Improved content and readability.
  • Improved cross-browser compatibility.
  • Capture configuration: Add .pcap extension to the file name when it was not given.
  • Add "refresh" functionality on filesystem listings (captured files, support archives).

• Wireshark

  • Update to Wireshark 2.6.4

Bugfixes

• Firmware

  • Minor bugfixes

• System and services

  • Upstream synchronization no longer fails in certain downstream channel bonding configurations.
  • Fixed possible segmentation faults due to incorrect incoming (packet) data.
  • Fixed some multi-threaded access issues.
  • Better handling of channel configuration versus status information.
  • Fixed some occasional problems during firmware updates.

• WebAdmin (GUI)

  • Fixed issues with handling file and directories with special characters in their name.
  • Several minor bug fixes

Known Issues

• Firmware

  • OFDM

    • The first channel locking step after a system reset or a CMTS change can take considerably longer than subsequent locking steps. This is because internal frequency offset has to be reliably estimated (after which it is cached).
      
      This effect is considerable on small-bandwidth OFDM channels. Depending on PLC frequency and FFT size, initial locking of a 24 MHz channel (the minimum allowed per [CM-SP-PHYv3.1]) can take up to 10 minutes. Subsequent re-locking steps, even on different channels, should be on the order of seconds. A workaround is to first 'pre-lock' the XRA-31 on a dummy 192 MHz channel (which should take no longer than 1 minute), remove this channel and re-add the 24 MHz channel.

  • SC-QAM

    • MER can be significantly lower on annex A channels with low traffic load on some CMTSs. This is due to poor symbol scrambling (needed to maintain proper lock) caused by sub-optimal low-entropy payload sequences of null packets. A workaround is to generate some (possibly artificial) traffic on the affected channels.

• System and services

  • During the OFDMA locking phase, the XRA-31 estimates the optimal time and power offset for demodulation (comparable to the ranging process of a cable modem). After RF network changes, primary OFDM or OFDMA channel configuration changes, or due to drift over long time periods, these estimations can deviate considerably from their initial value, leading to demodulation failures for data bursts. In a future release, the XRA-31 will continuously track and update time and power offset after locking.
    
    In the meantime, as a workaround for the above described cases, please remove and re-add the OFDMA channel to force a new locking phase. Note that you can keep track of the XRA-31 internal time offset by inspecting the Wireshark XRA header of the fine ranging signals.
  • The system accepts file names longer than 255 characters and starts capturing, but storing the file fails in this case.

• WebAdmin (GUI)

  • Multi-user access shows incomplete or invalid status information.
    • This is seen when connecting with multiple users (or browser tabs) to the WebAdmin.
    • Also unexpected error messages may be shown.
  • The XRA-31 Control Daemon exits when the FPGA firmware is not supported. The GUI has no way to properly show this state to the user and the user is just prompted with an error that connection to the XRA-31 server failed. This can happen for example when an update of the firmware failed. The user can detect this state by verifying that the firmware versions on the System page do not match.
  • Layout on small displays can be improved.

Welcome

We are pleased to announce the new release of the XRA-31 system!

We hope unboxing was a pleasure and you are up-and-running for this new experience!

This release brings both bug fixes and new features.

Features

• New since 1.1!

  • Re-defined the lock state of the downstream channels
    • No lock
    • PLC-only lock
    • Full lock
  • Capturing is now allowed even when the downstream channel has no lock or PLC-only lock.
  • The PLC MER is now available.
  • Update to Wireshark 2.4.5 with Excentis patches

• New since 1.1.2!

  • Customer informationcan be obtained via WebAdmin (GUI) or xra31-admin customer-info (CLI)
  • Update to Wireshark 2.4.6 with Excentis patches

• OFDM

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 2 Gbps per channel)
  • All FFT sizes, cyclic prefixes and rolloff periods defined by [CM-SP-PHYv3.1]
  • All interleaver settings defined by [CM-SP-PHYv3.1]
  • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1]
  • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1]
  • Multiple concurrent data profiles (from A up to P)
  • Mixed-modulation profiles
  • Dynamic data profile changes
  • PLC and NCP MER statistics

• OFDMA

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 1 Gbps per channel)
  • All FFT sizes, cyclic prefixes and rolloff periods defined by [CM-SP-PHYv3.1]
  • All interleaver settings defined by [CM-SP-PHYv3.1]
  • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1]
  • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1]
  • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently
  • Dynamic UCD changes (including data profile IUC changes)
  • Supported pilot patterns: 1-4, 8-11
  • Initial Ranging and Fine Ranging MER statistics

References

• [CM-SP-PHYv3.1]      DOCSIS 3.1 Physical Layer Specification (version I13 or any later version; http://www.cablelabs.com/specs/ )
• [CM-SP-MULPIv3.1]   DOCSIS 3.1 MAC and Upper Layer Protocols Interface Specification ( version I14 or any later version; http://www.cablelabs.com/specs/ )

Known limitations

FPGA

• OFDM

  • One channel receiver supported
  • No dynamic NCP profile changes
  • No data MER statistics

• OFDMA

  • One channel receiver supported
  • Unsupported pilot patterns: 5-7, 12-14
  • No REQ messages
  • No probing sequences
  • No data MER statistics

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Changelog 1.1.2-417 (2018-06-05)

Improvements

• System and services

  • The user can now obtain the customer information either via command-line (xra31-admin customer-info) or via the WebAdmin System page.
  • Fixed some typo's in error messages.

• WebAdmin (GUI)

  • Added feedback bar after creating support archive.
  • Status is refreshed more frequently.
  • Some minor graphical changes (more compact tables, position of icons).
  • Added more tooltips.

• Wireshark

  • Update to Wireshark 2.4.6
  • Added UCD reassembly

Bugfixes

• System and services

  • Fixed selection of OFDMA channels when more than one is available.
  • Bugfix in reporting of input level when channel power is too low.
  • No longer invalidating the lock status for all OFDM profiles when one profile loses MAC lock.
  • Fixed possible erroneous packets due to race conditions in buffering.

• WebAdmin (GUI)

  • Fixed issue where edited parameters were displayed in the status bar before apply.
  • Fixed incorrect MER shown in status bar when the OFDM channel had PLC-only lock.
  • Fixed stability issue (status no longer fetched when something went wrong).

Known Issues

• System and services

  • Upstream synchronization may fail in certain downstream channel bonding configurations.

• WebAdmin (GUI)

  • Upload progress bar not does correctly display full upload process progress
  • In some rare occasions, selecting a different OFDMA channel fails (workaround = select and apply again)

Changelog 1.1-285 (2018-04-11)

Changes

• General

  • Re-defined the lock state of the downstream channels
    • No lock
    • PLC-only lock
    • Full lock
  • Capturing is now allowed even when the downstream channel has no lock or PLC-only lock.
  • The PLC MER is now available.

• FPGA

  • Reinitialize OFDM channel after self-test
  • Added extra OFDM channel status flags
  • Fixed amplifier communication lockup

• Wireshark

  • Update to Wireshark 2.4.5
  • Added expert info in case XRA payload is non-existent
  • Made sure UCD embedded in REGRSPMP does not overwrite REGRSPMP info
  • Fixed profile mapping

• WebAdmin (GUI)

  • System page has been finalized
    • Fixed download button of support archive
    • Added sorting on columns
  • Analyze page
    • Fixed download of capture via download button
    • Added sorting on columns
  • Capture page
    • Automatically adding .pcap extension to capture file
    • Selection dialogs have been moved for better visibility
  • Overall small bug fixes and look and feel.

• System

  • The xra31 user can now reset the state of the firmware self-test.
    • In case of firmware update failure the state can be reset so that a firmware update will be retried on next reboot.
  • The FPGA firmware is now forced to reboot when the system reboots.

Known Issues

• WebAdmin (GUI)

  • Sometimes the status shows a warning about the input level while the input level is OK.
  • Delete confirm dialog disappears after two seconds.
  • When editing PLC frequency value this appears in the status bar.
  • There's no confirmation when creating support archive.
  • Tooltip texts are not available everywhere yet.
  • The GUI rarely gets in a state showing "object not found" and "no more channel receivers available" errors

• Daemon

  • The lock status for all OFDM profiles is invalidated when one profile loses MAC lock

Welcome

We are pleased to announce the first release of the XRA-31 system!

We hope unboxing was a pleasure and you are up-and-running for this new experience!

Features

• OFDM

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 2 Gbps per channel)
  • All FFT sizes, cyclic prefixes and rolloff periods defined by [CM-SP-PHYv3.1]
  • All interleaver settings defined by [CM-SP-PHYv3.1]
  • All modulations from zero-bit-loading up to 4096-QAM defined by [CM-SP-PHYv3.1]
  • All possible configurations of exclusion bands defined by [CM-SP-PHYv3.1]
  • Multiple concurrent data profiles (from A up to P)
  • Mixed-modulation profiles
  • Dynamic data profile changes
  • PLC and NCP MER statistics

• OFDMA

  • Real-time demodulation and decoding
  • Full line rate (up to approx. 1 Gbps per channel)
  • All FFT sizes, cyclic prefixes and rolloff periods defined by [CM-SP-PHYv3.1]
  • All interleaver settings defined by [CM-SP-PHYv3.1]
  • All modulations from zero-valued up to 4096-QAM defined by [CM-SP-PHYv3.1]
  • All possible configurations of exclusion bands and unused sub-carriers defined by [CM-SP-PHYv3.1]
  • All data profile IUCs defined by [CM-SP-MULPIv3.1] concurrently
  • Dynamic UCD changes (including data profile IUC changes)
  • Supported pilot patterns: 1-4, 8-11
  • Initial Ranging and Fine Ranging MER statistics

References

• [CM-SP-PHYv3.1]      DOCSIS 3.1 Physical Layer Specification (version I13 or any later version; http://www.cablelabs.com/specs/ )
• [CM-SP-MULPIv3.1]   DOCSIS 3.1 MAC and Upper Layer Protocols Interface Specification (version I14 or any later version; http://www.cablelabs.com/specs/ )

Known limitations

FPGA

• OFDM

  • One channel receiver supported
  • No dynamic NCP profile changes
  • No data MER statistics

• OFDMA

  • One channel receiver supported
  • Unsupported pilot patterns: 5-7, 12-14
  • No REQ messages
  • No probing sequences
  • No data MER statistics

Environment and system tools

• xra31-admin: It is not possible to follow the system/service logs

Analysis

• Captured packets are not ordered by timestamp

Changelog 1.0-235 (2018-03-07)

• First public release

Excentis actively contributes to the Wireshark community to integrate the XRA-31 support and improve the DOCSIS protocol parser.

The results of these efforts are now available in the official release of Wireshark 2.6!

The Excentis version 2.6 of Wireshark is based on the official Wireshark 2.6 releases.
It enhances the well-known network analysis tool with pre-release enhancements and bug fixes for Excentis' XRA-31.

Download

You can download the latest Excentis version of Wireshark from these locations:

• [[SecureDownload:XRA-31/wireshark/2.6.8-excentis63/Wireshark-win64-2.6.8-excentis63.exe:Wireshark Windows 64-bit installer]]

You can download the latest Wireshark releases from the official website:

• Wireshark downloads page

Known limitations

• SID decoding not always correct in RNG-REQ
• Some DOCSIS TLVs are not decoded yet

Changelog 2.6.8-excentis63 (2019-05-07)

• Update base to the official Wireshark 2.6.8

Changelog 2.6.5-excentis57 (2018-12-11)

• Update base to the official Wireshark 2.6.5
• Fixed wrongly dissected REG-REQ-MP.
• Add missing decoding of many DOCSIS 3.1 TLVs.

Changelog 2.6.4-excentis51 (2018-10-26)

• Update base to the official Wireshark 2.6.4
• Add XRA-31 downstream SC-QAM decoding.
• Support for defragmentation of multipart Mac Management Messages.
• The HCS of the segment header is now verified.
• The parts of the UCD OFDMA timestamp snapshot are now decoded (D3.0 timestamp and minislots).
• The parts of the PLC timestamp are now decoded (epoch, D3.0 timestamp, extra 204.8 MHz samples, extra 16*204.8 MHz samples).
• Decoding of several DOCSIS TLVs (Peak Traffic Rate, T4 timeout multiplier, diplexer band edge, full duplex descriptor, …)
• CM-Status messages are now correctly decoded.
• Indication of encrypted payload in Info column.

Changelog 2.6.0 (2018-04-24)

• Official Wireshark 2.6.0 release notes.
• Almost all Excentis XRA-31 patches have been integrated.
  • Missing features in comparison with Wireshark 2.4.6 with Excentis patches
    
    • expert info in case XRA payload is non-existent
    • UCD reassembly

The Excentis version 2.4 of Wireshark is based on the official Wireshark 2.4 releases.
It enhances the well-known network analysis tool with support for Excentis' XRA-31.

Download

You can download the latest Excentis version of Wireshark from these locations:

• [[SecureDownload:XRA-31/wireshark/2.4.6-excentis39/Wireshark-win64-2.4.6-excentis39.exe:Wireshark Windows 64-bit installer]]

Known limitations

• OPT dissection does not support reassembly yet

Changelog 2.4.6-excentis39 (2018-05-15)

• Update base to the official Wireshark 2.4.6
• Added UCD reassembly

Changelog 2.4.5-excentis31 (2018-03-31)

• Update base to the official Wireshark 2.4.5
• Added expert info in case XRA payload is non-existent
• Made sure UCD embedded in REGRSPMP does not overwrite REGRSPMP info
• Fixed profile mapping

Changelog 2.4.4-excentis21 (2018-03-05)

• Added SID, IUC and US Channel ID sub-TLVs to Burst Info TLV

Changelog 2.4.4-excentis14 (2018-02-05)

• Initial release
• Based on the official Wireshark 2.4.4
• Included Excentis patches