[c-nsp] BGP peer/customer routes

[Vitkovsky, Adam]

Right, got the point -than the trafic would have to pass the expensive upstream links and that would not be desirable

Filtering just the more specifics on AS10's peering and upstream links sounds good + offer community so that AS5 can mark the routes they advertise to AS10 as backup (prefix would get low local-pref within AS10 and would get as10 prepended when sent to AS10's transit)
-in case AS5 would like to use AS10 as the backup provider

But what if AS5 is a content provider and all the AS10 customers would now have to use the peering links ruining the tx/rx ratio :)


adam
-----Original Message-----
From: Gert Doering [mailto:gert at greenie.muc.de] 
Sent: Wednesday, June 01, 2011 9:14 AM
To: Vitkovsky, Adam
Cc: vince anton; cisco-nsp
Subject: Re: [c-nsp] BGP peer/customer routes

Hi,

On Tue, May 31, 2011 at 03:17:11PM +0200, Vitkovsky, Adam wrote:
> I believe the new customer questionnaire should query customers as to who they use as transit 
> -and if one of the customer upstream ISPs happens to be your peer 
>  than you should not advertise prefixes of the particular customer to that peer
> -and also update your peer inbound filter with your customer prefixes/ASNs

Bad advice.  What happens if one of the customer uplink fails?  Then you
*need* the interconnection to ensure they still have reachability to that
AS.

Now, filtering out more-specifics coming in from your peer but not
announced by the customer to you (thus redirecting incoming transit
traffic out the peering link) might make sense.

gert
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