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When the RFC number moves

SDP, ICE, STUN, and TURN moved. The RFC Editor banner beats a blog, and an uncited successor stays an open question.

Learn in 5 minutes

  1. Name the four moves this edition teaches
  2. Read Obsoletes on the header
  3. Mark a possible newer RFC this library does not cite

Visual

Which number is on which hop · study drawing · cyphermonkeylabs.com AliceSBCBob INVITE 100 INVITE 180 180 200 200 ACK

SVG HTML PNG

Confirm each Obsoletes line on rfc-editor.org. A later banner outranks this table.

Worked example

Cite the offer The first INVITE carries SDP. Which number is current in this library?

  1. Press Play.
  2. Step until the hop named in the question.
  3. Inspect that message and answer the check.

Fault

A design freezes SDP as RFC 4566 and ICE as RFC 5245, and it says the table in class cannot be wrong even if the RFC Editor shows a newer document.

This edition's current numbers are 8866 and 8445. An uncited successor on the banner still wins.

Quiz

Current SDP in this library is


ICE in this library is


STUN and TURN in this library are


A blog that calls RFC 4566 current


If a newer RFC obsoletes RFC 8656 and this edition does not cite it


RFC 6026 relative to RFC 3261 is


Ecosystem

Glossary, sister systems, and the integration seam for this room.

Workforce management WFM forecasts volume and builds schedules. It consumes contact-center events. It does not parse Via headers. When a forecast is wrong, the SIP symptom is usually queue delay and 480 or carrier congestion, not a broken dialog ID.

Programmable communications APIs Twilio’s docs home is API reference, tutorials, and integration for Twilio products. Elastic SIP Trunking is the SIP-shaped product already cited in this lab. This page does not define the word CPaaS from an RFC. Read the vendor page before you copy a diagram that uses that word.

Glossary · Ecosystem map · Ports · Troubleshooting

Sources and go deeper