Description
This article describes how to traffic shape or prioritize traffic locally originating traffic using ToS or DSCP.
Scope
FortiGate.
Solution
There are two types of traffic mapping: Type of Service (ToS) or DSCP (Differentiated Services Code Point).
Only one method can be used at a time, with ToS set as the default method.
The type used and attributes can be set in the CLI.
To set ToS or DSCP traffic mapping:
config system global
set traffic-priority {tos | dscp} <- Default value TOS.
set traffic-priority-level {low | medium | high} <- Default value High.
end
This means, by default, the local traffic will always have the highest priority.
Mapping of DSCP and ToS hexadecimal values for QoS.
| Service Class |
DSCP
Class |
DSCP Bits |
DSCP Value |
ToS Value |
ToS Hexidecimal |
| Network Control |
cs7 |
111000 |
56-63 |
224 |
0xE0 |
| Internetwork Control |
cs6 |
110000 |
48-55 |
192 |
0xC0 |
| Critical - Voice Data (RTP) |
ef |
101110 |
46 |
184 |
0xB8 |
| cs5 |
101000 |
40 |
160 |
0xA0 |
| Flash Override Video Data |
af43 |
100110 |
38 |
152 |
0x98 |
| af42 |
100100 |
36 |
144 |
0x90 |
| af41 |
100010 |
34 |
136 |
0x88 |
| cs4 |
100000 |
32 |
128 |
0x80 |
| Flash Voice Control |
af33 |
011110 |
30 |
120 |
0x78 |
| af32 |
011100 |
28 |
112 |
0x70 |
| af31 |
011010 |
26 |
104 |
0x68 |
| cs3 |
011000 |
24 |
96 |
0x60 |
| Immediate Deterministic (SNA) |
af23 |
010110 |
22 |
88 |
0x58 |
| af22 |
010100 |
20 |
80 |
0x50 |
| af21 |
010010 |
18 |
72 |
0x48 |
| cs2 |
010000 |
16 |
64 |
0x40 |
| Priority Controlled Load |
af13 |
001110 |
14 |
56 |
0x38 |
| af12 |
001100 |
12 |
48 |
0x30 |
| af11 |
001010 |
10 |
40 |
0x28 |
| cs1 |
001000 |
8 |
32 |
0x20 |
| Routine - Penalty Box |
|
000010 |
2 |
8 |
0x08 |
| Routine - Best Effort |
|
000000 |
0 |
0 |
0x00 |
In earlier versions of FortiOS v6.4, v7.0, and v7.2, the above commands were the only ones that could be used to change traffic priority.
Starting FortiOS v7.4+ supports DSCP and VLAN CoS marking for both local-in and local-out traffic. See the documentation for this.
