Polycom 4300T Benutzerhandbuch

 Configuring the 4300T

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• Controls the data transfer rate of far-end WAN TCP devices to limit WAN 

link congestion.

• Supports network-based QoS applications by setting the TOS bits for all 

VoIP packets sent to the WAN and the LAN. TOS bits are used so that 

VoIP packets can be prioritized in the network by DiffServ enabled 

routers.  The TOS bit value used by the 4300T is to “minimize delay and 

maximize throughput”, or 0xb8 hexadecimal.  This value is set for all VoIP 

packets processed by the 4300T and overwrites any specific TOS bit 

configuration set by VoIP endpoints.  

• Ensures that bandwidth allocated to new voice and video calls does not 

adversely affect the quality of existing active calls (Call Admission Control 

or CAC).

The 4300T combines sophisticated traffic management mechanisms including 

classification, prioritization, queuing, rate limiting and CAC to ensure high 

quality voice and video calls.  Fortunately the system manages this complexity 

for you and configuring traffic management is very straightforward:

Enable traffic shaping.

Specify the upstream and downstream bandwidth of your WAN link. 

Enable CAC.

Please follow the steps below to configure and enable traffic management.

From the Configuration Menu, select Traffic Shaper.

Select the Enable traffic shaper checkbox.