Toshiba CTX28 Strata Net Qsig Over IP and IPT Bandwidth Requirements, Class, Kbps, WAN MTU ms

IP Telephony and QSIG Over IP

Private Networking Over Internet Protocol

Strata Net QSIG Over IP and IPT Bandwidth Requirements

The bandwidth requirements for Strata Net QSIG over IP is the same as those for IP telephones. Refer to Table 9-1 on page 9-5to estimate the quality of service (Excellent, Good, Fair, and Poor) provided by CTX IP QSIG channels depending heavily on the LAN parameters.

When sharing voice and data on the same network segment, the data will cause some jitter in voice communications, especially on slower segments. Table 9-11shows calculations of the amount of jitter assuming a worst case data packet size of 1500 bytes (Maximum Transmission Unit (MTU) = 1500) based on a segment’s bandwidth. This also requires that the routers connecting the segment through the WAN support Diffserv.

Note A router that doesn’t support Diffserv may stack multiple data packets together increasing the jitter perhaps indefinately. And the voice quality will be indeterminate.

Table 9-11 QSIG over IP Jitter on Mixed Voice and Data WAN

No. of	Bandwidth	Time to	Expected
B-Channels		transmit max.		Class
	(kbps)		Jitter (ms)
of WAN		MTU (ms)
2	128	93.75	100	Poor
4	256	46.88	50	Fair
6	384	23.44	30	Fair
8	512	15.63	20	Good
24	1536	1.00	1	Excellent

Class definition categories are shown in Table 9-12.

Table 9-12 QSIG over IPClass Definitions

Class	Delay (ms)	Jitter (ms)
Excellent	< 20	< 10
Good	< 50	< 20
Fair	< 100	< 50
Poor	< 200	< 100

IP Telephony and QSIG Over IP

Table 9-13shows the amount of bandwidth required for setting up and tearing down calls independent of the amount of voice traffic.

Table 9-13 QSIG over IP Bandwidth

Required for Call Setup

Traffic Rate	Required
(BHCA1)	Bandwidth
1000	6
2000	12
4000	23
6000	36

1. BHC = Busy Hour Call Attempts

Strata CTX I&M 06/04 9-41