Revision as of 04:20, 23 November 2013 edit ChrisGualtieri (talk \| contribs) Pending changes reviewers, Rollbackers 457,369 edits m Checkwiki 61 + General Fixes, added orphan tag using AWB ← Previous edit		Revision as of 21:04, 26 February 2014 edit undo Dthomsen8 (talk \| contribs) 498,600 edits m →SBC Handling of Media Packets and NAT Traversal: clean up, typo(s) fixed: 87.2 kbps → 87.2 kbit/s using AWB Next edit →
Line 45: It is important to know that while this mostly works, it has several limitations. First of all, it only works with clients that are built "symmetric way", i.e., they use the same port for sending and receiving media. Nowadays that's fortunately the majority of available equipment. The other noticeable disadvantage is "triangular routing": an SBC must relay all VoIP traffic for a call, to make the paths caller-SBC and SBC-callee symmetric. That is in fact quite an overhead for a VoIP operator. With the most common codec, [[G.711]], a relayed call consumes four 87.2 ~~kbps~~kbit/s streams: two outbound, two inbound. Some other disturbing limitations may occur too. For example, if a SIP device uses [[Voice Activity Detection]] (VAD) and fails to send any voice packets initially, the SBC will not learn its address and will not forward incoming media to it as well.

NAT traversal with session border controllers: Difference between revisions