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Chapter 3: Applications and Configuration Overview
Avidia System Configuration and Management User Manual
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Traffic Management for Dual Homing
When implementing dual homing, you can create backup PVCs and configure static load 
sharing to both line cards in an Avidia system. Account for these variables when setting up 
a system:
the number of VPCs and VCCs that can be switched from a primary to a second line card
the number of VPCs and VCCs mapped full time to each line card
the traffic contract and quality of service (QOS) you apply to each VPC and VCC
the policing, through the Usage Parameter Control (UPC), that applies to the connection
The traffic contract and policing you select is dependent on the service you provide. The traffic 
contract and policing selection should maximize the network throughput and minimize 
end-to-end delays, thus efficiently utilizing the network. To set up your system:
Create ATM profiles for the service you will supply (upstream and downstream rates and 
the QoS must be supported end-to-end). See 
 for the traffic types that are available.
Configure service as described in the sections for command-line or Web interface.
Set up UPC policing. The policing function monitors and regulates traffic flow at the 
interface to ensure the traffic conforms to the configured traffic contract (see 
 for information about the traffic contract). Policing protects the 
network from intentional or unintentional changes in the traffic contract that could affect 
other connections. If you enable policing and traffic does not conform, it is deleted. 
Policing validates parameters such as VPI/VCI values, traffic rates conforming to contract. 
Policing can be enabled per one of the following:
ATM port
VPC
VCC
When implementing dual homing and redundancy, a failure of the primary line card switches 
traffic to the secondary line card. This can result in too heavy a traffic load on the second line 
card. To handle this, you can configure the recovery priority by traffic type (for example, 
CBR first, rt-VBR second). If you do not configure recovery priorities, the connections are 
recovered sequentially until no further resources are available. After that point, the remaining 
connections are dropped.