Session Based Statistics

The first 3 statistics listed by the show sipd codecs are session based. These statistics are titled Transcoded, Transrated, and Transparent.

• transcoded—counts of sessions that use the Transcoding NIU’s TCUs to transcode between two or more codes.
• transrated—counts of sessions that use the Transcoding NIU’s TCUs to change the packetization interval among dialogs in the session.
• transparent—counts of sessions that require no TCU hardware intervention (all end-to-end media uses the same codec)

A value of "none" which is not counted in the statistics is set when there is no media at all or media is not yet negotiated. Sessions within the same realm are counted only once.

These are meter type counters, and thus have an "active" count as well as total lifetime values. The media-processing state of the session only can increase in precedence (highest=transcoded, transrated, transparent, lowest=none). Thus, if a session begins as transcoded, and then is re-negotiated to transparent later by a re-INVITE, it is still considered transcoded. However, if a session begins as transparent, it can go to transcoded by a re-INVITE. In such a case, the total counts for both transparent and transcoded would be incremented. If there are several media lines, the highest precedence is used for the session.