Altigen AltiContact Manager Version 4.6, Руководство администратора

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VoIP Configuration
AltiContact Manager Administration Manual 9-9
9
.V
o
IP
Configur
a
tion
WAN Bandwidth
• G.711/G.723 compression and bandwidth requirements:
(for example, a Multilink Point-to-Point Protocol (MLPPP) or Frame
Relay Forum (FRF), with no Voice Activity Detection (VAD)
running)
— G711 10ms packet frame = 100.8 kbps
— G711 20ms packet frame = 82.4 kbps
— G711 30ms packet frame = 76.3 kbps
— G723 30ms packet frame 6.4k rate = 18.7 kbps
If you are running G.723.1 compression, you should reserve 17 kbps
WAN link bandwidth for each channel.
• When a small data application (e.g. one FTP transfer session) is
running across the same WAN as AltiWare IP, make sure bandwidth
is reserved for data traffic. An example would be, if you have 64 kbps
WAN link, you can run one G.723.1 session concurrently with one
FTP file transfer session, provided that the router fragments each TCP
packet to 500 bytes.
• The Jitter Buffer should be adjusted according to the bandwidth
allocated to data traffic. For example, a long Ethernet packet
(approximately 1500 bytes) traversing through a WAN which is
allocated with 256 kbps of data traffic bandwidth will take about 50
milliseconds. The Jitter Buffer value should be set to this WAN link
transmission delay plus the typical network jitter delay. Refer to
“Triton VoIP Trunk Configuration” on page 7-13 for more information
on how to configure the Jitter Buffer.
• If you have heavier data applications running concurrently, the
bandwidth reserved for data traffic should be increased.
• If your router supports multilink or TCP fragmentation, configure your
WAN router to user smaller packet sizes, e.g. 500 bytes.
WAN Router Configuration
• The router which connects your LAN and the WAN should support
priority queuing.