Cisco Cisco IOS Software Release 12.2(14)ZA

GPRS load balancing with GTP cause code inspection enabled has the following characteristics:

Must operate in directed server NAT mode.

Supports stateful backup. See the 

 for more information.

Tracks the number of open PDP contexts for each GGSN, which enables GGSN server farms to use 
the weighted least connections (leastconns) algorithm for GPRS load balancing. See the 

 for more information about this algorithm.

Enables IOS SLB to deny access to a virtual GGSN if the carrier code of the requesting International 
Mobile Subscriber ID (IMSI) does not match a specified value.

Enables IOS SLB to account for secondary PDP contexts even without DFP.

The Home Agent Director load balances Mobile IP Registration Requests (RRQs) among a set of home 
agents (configured as real servers in a server farm). Home agents are the anchoring points for mobile 
nodes. Home agents route flows for a mobile node to its current foreign agent (point of attachment).

The Home Agent Director has the following characteristics:

Can operate in dispatched mode or in directed server NAT mode, but not in directed client NAT 
mode. In dispatched mode, the home agents must be Layer 2-adjacent to the IOS SLB device.

Can operate in both fast and CEF switching modes.

Does not support stateful backup. See the 

 for more 

information.

Delivers RRQs destined to the virtual Home Agent Director IP address to one of the real home 
agents, using the weighted round robin load-balancing algorithm. See the 

 for more information about this algorithm.

For more information about Mobile IP, home agents, and related topics, refer to the Cisco IOS IP 
Configuration Guide, Release 12.2.

Semantic error in TFT operation

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Syntactic error in TFT operation

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Semantic error in packet filter

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Syntactic error in packet filter

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Mandatory IE incorrect

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Mandatory IE missing

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Optional IE incorrect

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Invalid message format

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Version not supported

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