Quality of Service (QoS): Managing Bandwidth More Effectively
Using QoS Classifiers To Configure Quality of Service for Outbound Traffic
Figure 8-23 shows an example of the ToS byte in the header for an IPv4 packet,
and illustrates the diffserv bits and precedence bits in the ToS byte. (Note that
the Precedence bits are a subset of the Differentiated Services bits.)
Field: Destination
MAC Address
Source MAC
Address
802.1Q Field Type &
Version
ToS Byte …
Packet: FF FF FF FF FF FF 08 00 09 00 00 16 08 00 45
E 0 ...
Differentiated Services Codepoint
Rsvd.
Precedence
Bits
1 1
E 0
0 0 0 0 0 1
Figure 8-23. The ToS Codepoint and Precedence Bits
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