Clear Channel Fax Transmission
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Clear Channel Fax Transmission
Modulated Fax information from the PSTN is passed in-band end-to-end over a voice speech
path in a IP network.
There are 2 pass-through techniques.
•
The configured voice codec is used for fax transmission. This technique works only when the
configured codec is G711 with no VAD and no echo cancellation (EC) or when the configured
codec is a clear channel codec or G.726/32. Low bit-rate codecs cannot be used for fax
transmission.
•
Gateway dynamically changes the codec from the codec configured for voice to G.711 with no
VAD and no EC for the duration of the fax session. This method is referred to as "codec up
speed" or "fax pass-through with up speed".
PROs
•
Less intrusive, does not modify the packets
•
Does not allows for redundancy
•
Takes less bandwidth than a T.38 fax transmission
•
The bandwidth usage is practically constant.
•
Bandwidth only affected by the P-Time.
CONs
•
Sensitive to network imperfection like packet loss or jitter
Configuration
Summary of Contents for TA7100 Series
Page 1: ...Mitel TA7100 58014903 REV00 STANDARD FAX CONFIGURATION...
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