Avaya 38DHB0002UKDD Manuel D’Utilisation

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How Do I? 
Part 2 Voice Over IP - Page 97 
Step 3 - Configure IP Connectivity 
Configure the IPNC for the appropriate IP connectivity option. 
IP Connectivity Options 
LAN 10/100 Ethernet 
The IPNC transmitted VoIP packets to LAN are distinguish with the TOS field 
setting. In this case it would be the function of other systems on the LAN to 
ensure that voice traffic is protected from delay. 
Lease line (PPP) 
Avaya QoS for Slow Speed WAN links ensure that non-voice traffic does not 
adversely affect the delay sensitive VoIP stream. The Avaya QoS can also be 
configured to interoperate with a 3rd party router over a WAN link. 
Frame Relay 
Using Frame Relay with PPP encapsulation it is possible to provide VoIP over 
Frame Relay between two INDeX systems. 
Digital services 
The term Digital service to refers to QSIG, DPNSS ISDN-ePRI, ISDN-2e. The 
IPNC can be configured to provide VoIP over single or multiple (bundled) bearer 
channels. A single ISDN bearer channel, for example, can be used to support up 
to 5 concurrent VoIP calls. The bandwidth of a G711 VoIP call is equal to the 
bandwidth of a single bearer channel. Hence G711 compression is not supported 
for this connectivity type. 
 
QoS 
Operation 
The diagram below illustrates the operation of Avaya’s IPNC QoS mechanism for 
slow speed WAN links. 
 
Router 
IP Header 
Compression
Interface 
Multilink 
Fragmentation 
PPP Link 
Signalling 
Non-Voice 
Header
Comp. 
Multilink 
Voice
Traffic &
Signalling
Normal
Compressed 
V3 
Voice 
V2 
V1 
D1 
Non-Voice 
VPN Line 
D1-2 
V2 
D1-1 
V1 
 
Voice packets are transmitted with a fixed length and intervals (1x20ms) and 
must not be delayed through the interface. 
The illustration shows voice packets (V1, V2 and V3) and non-voice packet D1 
arriving at the PPP interface. The non-voice packet D1 is made to fit into the 
interval between successive voice packets. This is accomplished by processing 
large non-voice packets through PPP Multilink. The Multilink process “fragments” 
the larger non-voice packet (D1) into smaller components (D1-1 and D1-2) for 
serialization to the PPP link. Voice packets are not fragmented in this way. Layer 
3 (call control) packets are fragmented and inserted when bandwidth is available 
in the same way as non-voice packets. 
 
INDeX IPNC Cassette Administration Manual 
How Do I? - Page 97 
38DHB0002UKDD – Issue 7 (22/11/02) 
Part 2 Voice Over IP