IP Trunk3.01 (and later) traffic engineering 97
5Calculate bandwidth output. Refer to Table17 "Silence Suppression
disabled TLAN Ethernet and WAN IP bandwidth usage per IP Trunk
3.01 (and later) " (page 113) (Silence Suppression disabled). Tv/36
and Tx/36 indicate the average number of simultaneous callers.
This calculation requires perfectly queued and perfectly smooth
traffic.
Tv/36*bandwidth output per port = voice bandwidth per node (Bv)
Tx/36*bandwidth output per port = fax bandwidth per node (Bx)
Totalbandwidth (Bt) = Bv + Bx
For WAN calculation, consider only the larger of faxtraffic sent or
received.
6Adjust requirement for traffic peaking.
Peak hour bandwidth per node = Bt*1.3 (default)
—End—
Procedure 5 "Calculating IP Trunk 3.01 (and later) port and bandwidth
requirements" (page 98) is used to calculate IP Trunk 3.01 (and later)
port and, therefore, IP network bandwidth requirements. In the WAN
environment, the traffic parcel is defined for each destination pair (route).
The total node traffic should be sub-divided into destination pair traffic. The
rest of the calculation procedure continues to apply.
Example 1:
IP Trunk 3.01 (and later) ports and bandwidth engineering (Silence
Suppression enabled)
In this configuration example of 120 VoIPusers, each user generates four
calls using the IP network (originating and terminating) with an average
holding time of 150 seconds in the busy hour.
In the same hour,25 faxes were sent and 20 faxes received. The faxes sent
averaged3 pages, while the faxes received averaged 5 pages. The average
time to set up and complete a fax page delivery is 48 seconds.
The codec of choice is G.729AB, voice packetpayload is 30 ms. The fax
modem speed is 14.4 kbit/s and payload is 16.6 ms. How many IP Trunk
3.01 (and later) ports are needed to meet P.01blocking Grade of Service?
What is the traffic in kbit/s generated by this node to the TLAN subnet?
Follow the steps in Procedure 5 "Calculating IP Trunk3.01 (and later) por t
and bandwidth requirements" (page 98) to calculate IP Trunk 3.01 (and
later) port and bandwidth requirements.
Nortel Communication Server 1000
IP TrunkFundamentals
NN43001-563 02.01 Standard
Release 5.5 21 December 2007
Copyright© 2007, Nor tel Networks
.