NACK-Oriented%20Reliable%20Multicast%20(NORM)%20Update

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NACK-Oriented Reliable Multicast (NORM) Update

• Brian Adamson, et al.
• ltadamson_at_itd.nrl.navy.milgt

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Overview

• Updated NORM drafts to
• draft-ietf-rmt-pi-norm-revised-00, and
• draft-ietf-rmt-bb-norm-revised-00
• Incorporated comments from mailing list with
  respect to changes related to revised FEC
  Building Block and FEC Schemes documents
• Editorial changes, clarifications, and
  corrections to RFC 3940 (NORM PI) from comments
  received during past year.

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draft-ietf-rmt-pi-norm-revised-00

• Corrections
• Clearly defined Generic vs. FEC Specific
  portions of NORM EXT_FTI header extension format.
• Fixed problem with NORM_CMD(SQUELCH) packet
  format figure
• Specified baseline hdr_len for NORM messages
  where formerly omitted.
• Clarifications
• Clearly described NORM receiver behavior upon
  sender inactivity timeout (timeout-driven NACKing
  when NORM_CMD(FLUSH) are missed)
• No rate limiting of receiver congestion control
  feedback messages.
• Tie broken for CLR selection based on receiver
  with bigger RTT
• RECOMMENDED value for NORM_ROBUST_FACTOR
  specified
• Editorial
• Removed block partitioning algorithms and
  reference revised FEC BB
• Added reference to FEC Basic Schemes document
• Other
• Deprecated NORM_DATA flags for
  NORM_OBJECT_STREAM messages and defined use of
  former reserved field in FEC encoded portion of
  such messages as payload_msg_start field.
• Specified reduction of NORM congestion control
  probing rate when data transmission is inactive.

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Next Steps

• Incorporate any new comments received on current
  drafts
• Provide examples in NORM specification for
  fully-specified Reed Solomon FEC scheme
• Add more examples to NORM protocol document?
• Recommend for last call