AASTRA 480i User Manual

Advanced Network Settings

41-001129-00 Rev 09, Release 1.4.1

4-23

Configuring the IP Phones

ToS is an octet as a field in the standard IP header. It is used to classify the traffic 
of the different QoSs.

QoS provides service differentiation between IP packets in the network. This 
service differentiation is noticeable during periods of network congestion (for 
example, in case of contention for resources) and results in different levels of 
network performance.

Port 0 is the Ethernet connected to the network. Port 1 is the Ethernet used for 
passthrough to a PC (port 1 is not available on 9112i).

Differentiated Service (DiffServ) QoS is class-based where some classes of traffic 
receive preferential handling over other traffic classes.

The Differentiated Services Code Point (DSCP) value is stored in the first six bits 
of the ToS field.  Each DSCP specifies a particular per-hop behavior that is 
applied to a packet. 

The following parameters allow an administrator to configure ToS, QoS, and 
DiffServ QoS for VLAN: