NEC SL1100, Networking Manual

Page: 167 / 292

NEC SL1100 Issue 6.0
Networking Manual 9 - 33
Working in conjunction with IP precedence, the next 4 bits in the ToS field are
designed to influence the delivery of data based on delay, throughput,
reliability, and cost. However these fields are typically not used.
The following table shows the 8-bit ToS field and the associated IP
precedence bits.
Differential Services Code Point (DSCP)
DSCP stands for Differential Services Code Point (or Diffserv for short). It
uses the first 6 bits of the ToS field therefore giving 64 possible values.
The following list shows the most common DSCP code points with their binary
values and their associated names:
IP
Precedence
IP
Precedence
IP
Precedence
Delay Throughput Reliability Cost Not Used
1(on) here =
value of 4
1(on) here =
value of 2
1(on) here =
value of 1
DSCP Code
Points
Binary Values Names
000000 0 Best Effort (BE)
001000 8 Class Selector 1 (CS1)
001010 10 Assured Forwarding 11 (AF11)
001100 12 Assured Forwarding 12 (AF12)
001110 14 Assured Forwarding 13 (AF13)
010000 16 Class Selector 2 (CS2)
010010 18 Assured Forwarding 21 (AF21)
010100 20 Assured Forwarding 22 (AF22)
010110 22 Assured Forwarding 23 (AF23)
011000 24 Class Selector 3 (CS3)
011010 26 Assured Forwarding 31 (AF31)
011100 28 Assured Forwarding 32 (AF32)
011110 30 Assured Forwarding 33 (AF33)
100000 32 Class Selector 4 (CS4)
100001 34 Assured Forwarding 41 (AF41)
100100 36 Assured Forwarding 42 (AF42)
100110 38 Assured Forwarding 43 (AF 43)