[c-nsp] High Availability for CGSE - NAT44 - Inter Chassis Redundancy

[cisco-pe]

Guys,
Thanks for your replies...

1. Currently CGSE does not offer hot-standby so, even if you have two in one
chassis the sessions will have to be re-established (take the number of
sessions into consideration if you do not want very long outage)

Yes, the idea is to deploy cold-standby following the Cisco recommendations.
I dont know if the typical bank transactions using Internet could be
affected during the cut of services.


2. With inter-chassis fail-over you have to relay on routing protocols
convergence and ability to trigger routing convergence if only the CGSE card
fails, but not the RP or uplink line cards.
Good Point, I always were thinking on link failures, but not on RP or CGSE
problem,
Is it possible to use BFD to obtain a better switchover time during failures
on CGSE,RP or Line cars ?


3. Do you want the CGSE to participate in MPLS or not, if so are you running
TE or only LDP?
The TG is connecting to a MPLS Core running LDP, this point is not very
clear for me. At this moment the default route is advertise by the TG to the
BRAS using MPLS unicast IP forwarding using the MPLS Core. The BRAS is
receiving the default route in the global routing. In all the Cisco
documentation, the examples are using only ip routing scenarios, I can´t not
found an example using CGSE on MPLS environment using HA.


4. When the sessions are dropped some customers' sessions will not come back
automatically, user intervention will be necessary. Depending on your
customer base this might not be a big problem.
The solution will be deployed for resindential users using basically ADSL
and Metro Ethernet (900k residential users aprox).


5. How are you going to scale the solution when number of
subscribers/sessions increases?
    To add more CGSE cards...We are working in the capacity planning with
our customer.


6. Do you have to record all mappings between inside/outside IPs (for
example for lawful intercept, charging or some other reasons)?
    We will confirm if our customer are using these functionalities.


Best Regards.
Juan Carlos