2.2 Programming
Programming Guide
21
DSCP
HEX
CODEC Frame Settings
The amount of required bandwidth depends on the type of CODEC and the selected packet
sending interval. The tables below show the amount of bandwidth required for one VoIP
channel in each case:
Required Bandwidth for Voice Communication via LAN
CODEC
Packet Sending Interval
20 ms
30 ms
40 ms
60 ms
90 ms
G.711
87.2 kbps
79.5 kbps
75.6 kbps
—
—
G.729A
31.2 kbps
23.5 kbps
19.6 kbps
—
—
G.723.1 5.3 kbps —
20.8 kbps
—
13.1 kbps
10.5 kbps
G.723.1 6.3 kbps —
21.9 kbps
—
14.1 kbps
11.6 kbps
....
....
....
Bit 0
Bit 8
IP Header
Version
IHL
Total Length
Bit 15
Reserved
Reserved
Bit 32
IP Packet
Type of Service
DSCP: 0
DSCP: 1
DSCP: 62
DSCP: 63
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
....
....
....
....
....
....
....
....
....
Bit 0
Bit 8
IP Header
Version
IHL
Total Length
Bit 15
Bit 32
IP Packet
Type of Service
HEX: 0
HEX: 1
HEX: FE
HEX: FF
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
....
....
....
....
....
....
....
....
