Layer 3 / Diffserv - Siemens Asterisk OpenStage 20 Owner's Manual

administration.fm
Administration
IP Network Parameters
Administration via WBM
Network > QoS
Administration via Local Phone
|
--- Administration
|
--- Network
|
--- QoS
|
--- Service
|--- Layer 2
|--- Layer 2 voice
|--- Layer 2 signalling
|
--- Layer 2 default
3.3.1.2

Layer 3 / Diffserv

Diffserv assigns a class of service to an IP packet by adding an entry in the IP header.
Traffic flows are classified into 3 per-hop behavior groups:
1. Default
Any traffic that does not meet the requirements of any of the other defined classes is placed
in the default per-hop behaviour group. Typically, the forwarding has best-effort forwarding
characteristics. The DSCP (Diffserv Codepoint) value for Default is "0 0 0 0 0 0".
2. Expedited Forwarding (EF referred to RFC 3246)
Expedited Forwarding is used for voice (RTP streams) by default. It effectively creates a
special low-latency path in the network. The DSCP (Diffserv Codepoint) value for EF is
"1 0 1 1 1 0".
3. Assured Forwarding (AF referred to RFC 2597)
Assured forwarding is used for signaling messages by default (AF31). It is less stringent
than EF in a multiple dropping system. The AF values are containing two digits X and Y
(AFXY), where X is describing the priority class and Y the drop level.
Four classes X are reserved for AFXY: AF1Y (high priority), AF2Y, AF3Y and AF4Y (low
priority).
3-14
A31003-S2000-M102-1-76A9, 06/02/2009
Asterisk - OpenStage Family, Administration Manual