Avaya P333R-LB Manuel D’Utilisation

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Chapter 14
Load Balancing in the P333R-LB
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Avaya 
P333R-LB User’s Guide
Application Redirection
This section provides information on Application Redirection (AR), and includes a 
configuration example. 
With the importance of the Internet as an organization's source of information, 
normal operation of the LAN can be negatively impacted by congestion on the 
network router to the Internet.
Since much of the information retrieved from the Web is either repeatedly requested 
by a user or requested by multiple users, many organizations implement a local 
caching mechanism to prevent unnecessary WAN traffic.
The problem with local caches is that they must be on the traffic path between the 
client and the WAN router. As a result, all traffic, even non-cacheable traffic, passes 
through the caches.
The P333R-LB’s Application Redirection (AR) redirects packets from their original 
destination to an alternative server, based on AR configuration. Since redirecting 
Web requests to local caches is the most common implementation of AR, it is also 
known as Cache Redirection.
The AR feature can also be used for policy-based (source-based) routing. For full 
details, see Policy-Based Routing (Source-Based Routing) on page 57.
Benefits
By redirecting client requests to a local cache or application server, you can increase 
the speed at which clients access the information and free up valuable network 
bandwidth.
AR for cache redirection provides the following benefits:
Faster client access to information.
Increased network bandwidth.
Policy based routing.
Only suitable traffic is directed to the local cache.
Multiple caches can be connected and load-balanced.
The redirection process is transparent to the client.
Redundant caches can be configured.
How It Works
To enable AR, locate P333R-LB on the traffic route, instead of the local cache, and 
redirect packets from their original destination, the WAN access router, to 
alternative cache servers. The redirection process performs the following:
1
Checks whether the packet characteristics complies with one of the defined 
filter rules. You need to configure rules in order to define which clients/
destinations P333R-LB redirects to the cache applications.
2
Routes the packet to the cache server instead of the original destination, the