Typical bandwidth usage
You can use the following table to assess the bandwidth (in Kbits/sec) used for various types of codecs and packet sizes. The values shown have a 7–byte L2 WAN header (and are rounded up).
Table 1: Bandwidths used for codecs and packet sizes
Packet Size |
10 ms |
20 ms |
30 ms |
40 ms |
50 ms |
20 ms |
G.711 |
102 |
83 |
77 |
74 |
72 |
71 |
G.729 |
46 |
27 |
21 |
18 |
16 |
15 |
G.723-6.3 |
NA |
NA |
19 |
NA |
NA |
13 |
G.723-5.3 |
NA |
NA |
18 |
NA |
NA |
12 |
G.722.2 |
NA |
43 |
NA |
34 |
NA |
31 |
These values are not significantly different from the actual bandwidth used for 8–byte L2 WAN headers and 10–byte L2 WAN headers. In some cases, the rounded up values shown above are greater than the values used for 10 bytes.
The bandwidth usage numbers shown above have 6 bytes for Multilink Point-to-Point Protocol (MP) or Frame Relay Forum (FRF), 12 Layer 2 (L2) header, and 1–byte for the end-of-frame flag on MP and Frame Relay frames for a total of 7–byte headers only. They do not account for silence suppression or header compression techniques, which might reduce the actual bandwidth. For other types of networks (such as Ethernet or ATM) or for cases where there is a lot of silence suppression or header compression being used, the network is modeled by administering the CAC-BL limits in terms of number of connections rather than bandwidth used.
