Figure 5-9 Ethernet Frame Example - Containing One Rtp (Speech) Packet; Table 5-2 Diffserv Parameters; Diffserv (Differentiated Service) - NEC Univerge SV9100 Manual

Hide thumbs Also See for Univerge SV9100:

Table of Contents

Payload type=ITU-T G.729, SSRC=732771006, Seq=30885, Time=20560

Frame 159 (65 bytes on wire, 65 bytes captured)

Ethernet II, Src: 00:60:b9:c1:ab:a3, Dst: 00:60:b9:c6:6e:45

Internet Protocol, Src Addr: 172.16.0.21 (172.16.0.21), Dst Addr:

172.16.0.101 (172.16.0.101)

Differentiated Services (Diffserv) uses the ToS field in an IP header. Diffserv is

now commonly used instead of IP Precedence (refer to

5-23) as it provides greater flexibility. This method uses six bits of the ToS

field to determine the priority – which provides up to 64 possible values. The

combination of binary digits is known as the Diffserv Codepoint (DSCP).

Differentiated Services Code Point

The example below shows an Ethernet Frame containing one RTP (speech)

packet. The IP Packet has the ToS field set to 101000 (binary) which is the

equivalent of Class Selector 5. The router(s) in this network should be

programmed to prioritize based on CS5.

Figure 5-9 Ethernet Frame Example - Containing One RTP (Speech) Packet

172.16.0.101

Arrival Time: Jan 18, 2005 13:55:44.834497000

Time delta from previous packet: 0.000445000 seconds

Time since reference or first frame: 2.901831000 seconds

Frame Number: 159

Packet Length: 65 bytes

Capture Length: 65 bytes

Destination: 00:60:b9:c6:6e:45 (Nitsuko_c6:6e:45)

Source: 00:60:b9:c1:ab:a3 (Nitsuko_c1:ab:a3)

Type: IP (0x0800)

Header length: 20 bytes

Diff Services Field: 0xa0 (DSCP 0x28: Class Selector 5; ECN: 0x00)

1010 00.. = Diff Services Codepoint: Class Selector 5 (0x28)

.... ..0. = ECN-Capable Transport (ECT): 0

.... ...0 = ECN-CE: 0

7.4 IP Precedence on

(Not QoS related)

Network Design Considerations