User`s guide

Configuring MultiVoice
MultiVoice configuration examples
MultiVoice Gateway for the MAX— User’s Guide Preliminary November 23, 1998 6-11
Impact of configurable voice frames on IP packet size
The size of each IP packet is determined by the number of audio frames contained in each RTP
packet plus the size of the respective headers required to construct the frame.
The RTP packet header contains a time stamp and sequence number used to reconstruct the
voice message. The header size is fixed at 12 bytes. The size of the packet data will vary,
depending upon the type of audio codec defined for Pkt Audio Mode:
Table 6-1. Impact of configurable voice frames on IP packet size
Audio
codec
Number of
voice frames
RTP packet
size
Ethernet
frame size
G.729 1 @ 10ms ea. 22 bytes 64 bytes
2 @ 10ms ea. 32 bytes 74 bytes
3 @ 10ms ea. 42 bytes 84 bytes
4 @ 10ms ea. 52 bytes 94 bytes
5 @ 10ms ea. 62 bytes 104 bytes
6 @ 10ms ea. 72 bytes 114 bytes
7 @ 10ms ea. 82 bytes 124 bytes
8 @ 10ms ea. 92 bytes 134 bytes
9 @ 10ms ea. 102 bytes 144 bytes
10 @ 10ms ea. 112 bytes 154 bytes
G.723.1 1 @ 30ms ea. 32 Bytes 74 Bytes
2 @ 30ms ea. 52 Bytes 94 Bytes
3 @ 30ms ea. 72 Bytes 114 Bytes
4 @ 30ms ea. 92 Bytes 134 Bytes
5 @ 30ms ea. 112 Bytes 154 Bytes
6 @ 30ms ea. 132 Bytes 174 Bytes
7 @ 30ms ea. 152 Bytes 194 Bytes
8 @ 30ms ea. 172 Bytes 214 Bytes
9 @ 30ms ea. 192 Bytes 234 Bytes
10 @ 30ms ea. 212 Bytes 254 Bytes