Table 13-1 Bandwidth Per Voip Call; Section 5 Ip Precedence - NEC SL1100 Networking Manual

NEC SL1100
Below is a table that shows the average bandwidth per VoIP call over Ethernet.
Codec
G.711
G.711
G.711
G.711
G.722
G.722
G.722
G.722
For example, if one site plans on making a maximum of 16 calls across the network
using G.729 with a 30ms packet size, there must be a minimum of 376kbps available
for voice traffic. The QOS policy for this network should allow for 376kbps to be set
aside for voice prioritization.
Q
S 4
UALITY OF
ECTION
Quality of Service (QOS) is one of the most important factors for VoIP. QOS is used
to prioritize voice packets over data packets during times of network congestion.
There are many ways that QOS can be implemented in the network and one of the
most common ways QOS is implemented is by using IP Precedence or Diffserv. If the
networks QOS policy is based on IP Precedence or Diffserv then there are settings
required in the SL1100.
Program 84-10 is used to assign the IP Precedence or Diffserv Values per Protocol
Type. For SL Net only two protocol types will be selected. All signaling packets will
be marked with the values assigned for protocol type "H.323". All voice packets will
be marked with the values assigned for protocol type "RTP/RTCP".
IP P
S 5
ECTION
IP Precedence uses the first 3 bits of the TOS field to give eight possible precedence
values (0 ~ 7). Under normal circumstances the higher the number the higher the
priority. However this is left to the network administrator for setup. When assigning IP
Precedence values (for SL Net) go to program 84-10-01 and change the type from
Disabled to IP Precedence. Then in program 84-10-02 assign the value for the
Networking Manual

Table 13-1 Bandwidth per VoIP Call

Bandwidth
Packet Size
Used
10ms 110.4kbps
20ms 87.2kbps
30ms 79.5kbps
40ms 75.6kbps
10ms 110.4kbps
20ms 87.2kbps
30ms 79.5kbps
40ms 75.6kbps
S
ERVICE
RECEDENCE
Codec
G.729
G.729
G.729
G.729
G.729
G.729
G.723
G.723
S (QOS)
ETTINGS
Issue 6.0
Bandwidth
Packet Size
Used
10ms 54.4kbps
20ms 31.2kbps
30ms 23.5kbps
40ms 19.6kbps
50ms 17.3kbps
60ms 15.7kbps
30ms 20.8kbps
60ms 13.2kbps
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