Avaya 555-245-600 사용자 설명서

In circuit switched networks, trunks provide the means to interconnect PBXs with each other 
and to the PSTN. Connection to the public network allows PBX station users to call and be 
called by terminals that are not part of the PBX private network. An analogous arrangement 
exists in packet-switched IP networks. 
H.323 trunks connect H.323 systems or gateways over IP networks, similar to circuit-switched 
tie trunks. Similarly, SIP trunks connect SIP systems or gateways over IP networks.
A set of Communication Manager switches can each be attached to an IP network, and voice 
and fax calls can flow between them in the usual manner except that the call signaling and 
audio/fax streams are carried over the IP network. The signaling is carried through the C-LAN 
circuit packs, and the audio and fax streams are carried between switches through the Media 
Processor circuit packs. 
The benefits of using IP trunks include: 

●

Reducing long distance voice and fax expenses 

●

Facilitating global communications 

●

Providing a fully functional network with data and voice 

●

Converging and optimizing networks by using the available network resources 

IP trunk calls can be compressed to save network bandwidth. Repeated compression and 
decompression (transcoding) results in a loss of data at each stage and degrades the final 
quality of the signal. The maximum recommended number of compression cycles on a call is 
three. Normal corporate voice calls or fax calls typically go through fewer than three 
compression cycles. 
IP (H.323 and SIP) trunks can also connect to other vendors' compliant PBXs.

Default, 45.45 Baudot, interoperates with previous releases

50 Baudot

similar to Fax pass-thru

system ignores TTY tones, call remains in administered 

codec