any codec which uses compression tehcniques (g729, g726, g723) is unsuitable for fax pass through as the tones representing each sample on the original bitmap from the fax needs to reach the other end of the connection exactly as sent, and the only codec cabable of this is g711.
You can configure g729 codec on ATA and IOS devices for voice calls and switch to G711 as needed (called upspeeding on some documentation) but that doesn't mean your faxes are being carried by a g729 codec which is in fact impossible because this codec works upon the fact that the human hear is incapable of interpeting all the frequencies on the audio spectrum which on a regular phone line are limited to the 4 khz upper range, but fax machines do use precise tones which are turned into garbage by lossy codecs like G.729.
SIP traces provide key information in troubleshooting SIP Trunks, SIP
endpoints and other SIP related issues. Even though these traces are in
clear text, these texts can be gibberish unless you understand fully
what they mean. This document attempts to br...
Please find the attached HTML document, download and open it on your PC.
This provides an easy to use form where you simply answer a few
questions and it will render the proper jabber-config.xml file for you
to copy/paste. There is built in logic to verif...
CUCM Database Replication is an area in which Cisco customers and
partners have asked for more in-depth training in being able to properly
assess a replication problem and potentially resolve an issue without
involving TAC. This document discusses the bas...