[c-nsp] Inter-AS L2VPN redundancy, option B (Ruzhanskaya Olga)

[Phil Bedard]

If you are using BGP Signaling for L2VPN (Kompella style) Option B is  
an option but not for Martini-style LDP signaled pseudowires.  You  
would still need L2VPN inter-as support for option B, which I'm not  
sure Cisco even supports.

You could use option C with targeted LDP sessions between the remote  
ASBRs to exchange VC labels and then use MBGP between AS2/AS1 for  
transport between ASBR2/ASBR3.   The transport LSP can easily be made  
redundant.



Phil


On Sep 23, 2009, at 4:10 AM, Ольга Ружанская wrote:

> Hello List!
>
> My company is working on building Inter-AS VPN connection with other  
> provider (both using MPLS).
> After researching on different option we've decided to use Option B  
> (single-hop MP-EBGP).
> The only way to build l2vpn for option B is to use point-to-point  
> VFI on ASBRs:
> http://www.cisco.com/en/US/docs/ios/mpls/configuration/guide/mp_l2vpn_pseudo_swit_ps6922_TSD_Products_Configuration_Guide_Chapter.html#wp1059907
>
> We've found information how to build redundant schemes for L3VPN,  
> but redundancy for l2vpn is a problem..
> If we have the following topology (2 ASBRs in one AS with  
> connections to 1 ASBR in other AS):
> ASBR2(AS2)
>   |
> ASBR1(AS1)
>   |
> ASBR3(AS2)
> is it possible to build a redundant l2vpn?
>
> As I understand, to use L2VPN Pseudowire Redundancy, we need  
> directed control protocol between the peer routers, and there is no  
> such protocol (LDP, for example) in nature of option B.
> But maybe someone have already decided such question?
>
> I will be very glad for any suggestions/documents(it is so little  
> information about inter-as l2!)
>
> Best regards,
> Olga
>
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/