15. [tos] command
TOS/DiffServ (DS) priority function can discriminate the Differentiated Service
Codepoint (DSCP) of the DS field in the IP packet header, and map each Codepoint to a
corresponding egress traffic priority. As per the definition in RFC2474, the DS field is
Type-of-Service (TOS) octet in IPv4. The recommended DiffServ Codepoint is defined in
RFC2597 to classify the traffic into different service classes. The mapping of Codepoint
value of DS-field to egress traffic priorities is shown as follows.
1. High priority with DS-field.
(1) Expected Forwarding (EF) 101110 ====> 46 (Decimal System)
(2) Assured Forwarding (AF) 001010 ====> 10 (Decimal System)
010010 ====> 18 (Decimal System)
011010 ====> 26 (Decimal System)
100010 ====> 34 (Decimal System)
2. Low Priority with DS-field:
Assured Forwarding (AF)
001100 ====> 12 (Decimal System)
010100 ====> 20 (Decimal System)
011100 ====> 28 (Decimal System)
100100 ====> 36 (Decimal System)
001110
====>
14
(Decimal
System)
010110
====>
22
(Decimal
System)
011110
====>
30
(Decimal
System)
100110
====>
38
(Decimal
System)
000000 ====> 0 (Decimal System)
For example, to configure TOS at EV via Telnet command.
usr/config$ tos -rtptype 10
usr/config$ tos -sigtype 10
usr/config$ tos -print
IP Packet ToS information:
29
