[c-nsp] Peering + Transit Circuits

[Pshem Kowalczyk]

It's actually quite easy.
Provider1 is present at Exchange1 and Exchange2, so is Provider2. Provider2
doesn't want to pay for the traffic between Exchange1 and Exchange2, so it
points a static route for all prefixes it has in Exchange2 via Provider1's
IP address in Exchange1 and does the same in Exchange2. Provider1's router
receives traffic, checks where it should go (Exchange2) and it forwards the
traffic. So the traffic flows like this:

Provider2 (Exchange1) -> Provider1 -> (Exchange2) Provider2, all due to
static routes.

kind regards
Pshem


On Wed, 19 Aug 2015 at 10:38 Faisal Imtiaz <faisal at snappytelecom.net> wrote:

> Let me start backwards...
>
> To me 'peering' is sharing internal routes and downstream customer
> routes,and not external ones.
>     IP transit is all of the external routes including internal routes &
> downstream customer routes
>
>
> Having said that..... if one is control of what IP Prefixes get advertised
> to whom... how exactly someone (peers) 'steal' transit ?
> (If one is not managing the filters well then yes it is possible, but that
> would be a configuration error ?)
>
>
> Maybe I am naive, to my Peering routes (relationships) are a subset of IP
> Transit Routes (relationships)
>
> Based on above belief...
>
> Then Item # 3, becomes the choice of the OP.... where one can make one of
> two starting assumptions... We will trust everything coming in and change
> what we don't like... or We will not trust anything coming in, and change
> (accept) what we like.
>
> Items # 1 & 2, would be a function of network design, technical
> requirements (maintenance window) etc etc.. easier to deal with a
> distributed edge vs all in one when one has to bring anything down for any
> reason..
>
> I am open to learning and being corrected if any of the above is wrong !
>
>
> Faisal Imtiaz
> Snappy Internet & Telecom
>
> ----- Original Message -----
> > From: "Tim Durack" <tdurack at gmail.com>
> > To: cisco-nsp at puck.nether.net, "nanog list" <nanog at nanog.org>
> > Sent: Tuesday, August 18, 2015 8:29:31 AM
> > Subject: Peering + Transit Circuits
>
> > Question: What is the preferred practice for separating peering and
> transit
> > circuits?
> >
> > 1. Terminate peering and transit on separate routers.
> > 2. Terminate peering and transit circuits in separate VRFs.
> > 3. QoS/QPPB (
> >
> https://www.nanog.org/meetings/nanog42/presentations/DavidSmith-PeeringPolicyEnforcement.pdf
> > )
> > 4. Don't worry about peers stealing transit.
> > 5. What is peering?
> >
> > Your comments are appreciated.
> >
> > --
> > Tim:>
>