[cisco-bba] Problems to monitor resource usage using Radius in ios 12.3(10)

[RGCABELL]

Testing cisco ios 12.3(10) as a L2TP Network Server, I have noticed a 
different behaviour on PPPoL2TP sessions treatment regarding to ios 12.2
(24). 

Now a new L2TP session state is created when ICCN control packet is 
received: "wait-for-service-selection" instead of "established". The 
L2TP session is considered "established" when authentication process 
succeeds, and a virtual-access interface is assigned to the L2TP 
session. 

During the authentication process, the virtual-access interface is 
unknown, so the value for NAS-Port Radius attribute cannot contain the 
virtual-access any more. New ios version sends a "uniq-Sess-Id" 
assigned to L2TP session as NAs-Port value. 

I have tried to test the criteria to generate this new value, and I 
have seen that the value is a decimal number generated in sequential 
form. But, when the value is around "1004", it is wrapped and it starts 
at "1" again. 

I have tested it at two different platforms: 3725 and 7200, and the 
result is the same for them. 

Why Uniq-Sess-Id is wrapped around 1004? could it be solved with some 
configuration command? If not so, the monitorization of resource usage 
using Radius will not work properly if Radius server uses an IP address 
and a Port to identify a resource, and the number of simultaneous 
sessions is greater than 1004.