Application 77 - Vivotek CC8160 User Manual

QoS/DSCP (the DiffServ model)
DSCP-ECN defines QoS at Layer 3 (Network Layer). The Differentiated Services (DiffServ) model is
based on packet marking and router queuing disciplines. The marking is done by adding a field to the
IP header, called the DSCP (Differentiated Services Codepoint). This is a 6-bit field that provides 64
different class IDs. It gives an indication of how a given packet is to be forwarded, known as the Per Hop
Behavior (PHB). The PHB describes a particular service level in terms of bandwidth, queueing theory,
and dropping (discarding the packet) decisions. Routers at each network node classify packets according
to their DSCP value and give them a particular forwarding treatment; for example, how much bandwidth
to reserve for it.
Below are the setting options of DSCP (DiffServ Codepoint). Specify the DSCP value for each application
(0~63).
Note that different vendors of network devices might have different methodologies and unique
implementations. Shown below is a sample corresponding information from a Cisco switch. You should
enter a DSCP tag value according to the information provided by the network devices.
QoS Baseline/Technical Marketing Classification and Marking Recommendations
Application
IP Routing
Voice
Interactive Video
Streaming-Video
Locally-defined Mission-
Critical Data
Call-signaling
Transactional Data
Network Management
Bulk Data
Scavenger
Best Effort
Layer3 Classification
IPP PHB
6 CS6
5 EF
4 AF41
4 CS4
3 -
3 AF31/CS3
2 AF21
2 CS2
1 AF11
1 CS1
0 0
Layer 2 CoS/MPLS EXP
DSCP
48 6
46 5
34 4
32 4
25 3
26/24 3
18 2
16 2
10 1
8 1
0 0
VIVOTEK
32
QoS B
User's Manual - 77