The following are notes regarding QoS that I consider helpful for my work.
I will update this as I learn more.
Cisco's Differentiated Services Code Point (DSCP) Values for Various Types of Traffic
|
|
|
|
Call signaling
|
3
|
3
|
CS3 (24)
|
Voice
|
5
|
5
|
EF (46)
|
Video
|
4
|
4
|
AF41 (34)
|
TelePresence
|
4
|
4
|
CS4 (32)
|
Class selector values
| DSCP |
Binary |
Hex |
Decimal |
Typical application |
Examples |
| CS0 (Default) |
000 000 |
0x00 |
0 |
|
|
| CS1 |
001 000 |
0x08 |
8 |
Scavenger |
YouTube, Gaming, P2P |
| CS2 |
010 000 |
0x10 |
16 |
OAM |
SNMP,SSH,Syslog |
| CS3 |
011 000 |
0x18 |
24 |
Signaling |
SCCP,SIP,H.323 |
| CS4 |
100 000 |
0x20 |
32 |
Realtime |
TelePresence |
| CS5 |
101 000 |
0x28 |
40 |
Broadcast video |
Cisco IPVS |
| CS6 |
110 000 |
0x30 |
48 |
Network control |
EIGRP,OSPF,HSRP,IKE |
| CS7 |
111 000 |
0x38 |
56 |
|
|
Commonly used DSCP values
| DSCP value |
Hex value |
Decimal value |
Meaning |
Drop probability |
Equivalent IP precedence value |
| 101 110 |
0x2e |
46 |
Expedited forwarding (EF) |
N/A |
101 Critical |
| 000 000 |
0x00 |
0 |
Best effort |
N/A |
000 - Routine |
| 001 010 |
0x0a |
10 |
AF11 |
Low |
001 - Priority |
| 001 100 |
0x0c |
12 |
AF12 |
Medium |
001 - Priority |
| 001 110 |
0x0e |
14 |
AF13 |
High |
001 - Priority |
| 010 010 |
0x12 |
18 |
AF21 |
Low |
010 - Immediate |
| 010 100 |
0x14 |
20 |
AF22 |
Medium |
010 - Immediate |
| 010 110 |
0x16 |
22 |
AF23 |
High |
010 - Immediate |
| 011 010 |
0x1a |
26 |
AF31 |
Low |
011 - Flash |
| 011 100 |
0x1c |
28 |
AF32 |
Medium |
011 - Flash |
| 011 110 |
0x1e |
30 |
AF33 |
High |
011 - Flash |
| 100 010 |
0x22 |
34 |
AF41 |
Low |
100 - Flash override |
| 100 100 |
0x24 |
36 |
AF42 |
Medium |
100 - Flash override |
| 100 110 |
0x26 |
38 |
AF43 |
High |
100 - Flash override |
Cisco switch COS to DSCP fix
because EF (DSCP46) -> COS 5
but COS = 5 -> DSCP CS5 (40)
mls qos map cos-dscp 0 8 16 24 32 46 48 56