The MPLS-OPS Archive

[Maher Adib <maher@pd.jaring.my>]

Hi there,

Rajiv Asati wrote:
>> > If the customer service
>> > provider's sites have different AS numbers, then the BGP/MPLS VPN
>> transit
>> > service provider supports multi-AS operations."
>> > AFAIK, this refers to multi-carrier , interprovider(inter-AS?)
>> MPLS/BGP VPN's .....
> 
> 
> Not necessarily. If the motive is to provide the transport service, then
> CsC is still the way to go.
> Whether the ASN values are the same or not usually has no relevance to
> the above conclusion.

Yeap.I go agress about this. Even public or private ASN can be done
without overlapping ip addresses :)

> And this is no different from the usual VPN service. Think of it as the
> following -
>  1) If the VPN customer has the same ASN in all the sites, then the SP
> need to use "as-override"
>      to facilitate the CE routes being accepted at the other CEs.
>  2) If the VPN customer has unique ASN in each site, then the SP doesn't
> need to use
>      any special knob, since BGP (at the CE) would accept the remote
> site routes just fine.

This implementation I assume on BGP PE to CE links right?

> Now, the motive has changed. You want to service the same VPN customer
> which has sites spread across two SPs and want seamless VPN
> connectivity. Hence the need for Inter-AS, in which two SPs peer with
> each other at one or two locations. Of course, this requires agreements
> regarding number of VPN routes, amount of traffic, SLA, QoS etc to be
> negotiated.
> 
> Important to note that we are referring to "tie-up" -> Partnership here.

Lots of things involved here when doing Inter-AS.

> But keep in mind that if the same VPN customer is already serviced by
> two different SPs, then Inter-AS is only way to provide seamless VPN
> connectivity. CsC helps to provide the transport service to another
> (baby) SP, hence the VPN customer of baby SP will not be able to talk to
> the VPN customer of parent SP (without some heavy lifting and hair loss).
> 
Holding two or more SP..as the parent acting as a transit...

regards,

maher

-------
The MPLS-OPS Mailing List
Subscribe/Unsubscribe:  http://www.mplsrc.com/mplsops.shtml
Archive: http://www.mplsrc.com/mpls-ops_archive.shtml