[LINK] Peering nation-wide

[Martin Barry]

$quoted_author = "stephen at melbpc.org.au" ;
> 
> Peering 101
> -----------

This is more "Internet exchange 101". Peering can take many forms and
multi-party exchanges are just one of them.

You can look at AMS-IX, DEC-IX and LINX for insight into how these are setup
and run. I only picked those because they are the most transparent into
their practices.

 
> Find a neutral location
> 
> Create a Peering entity to run the place.
> 
> Peering entity obtains AS number and IP space (for BGP routing).

Just to be 100% clear the IP space is used for the BGP connections but is
never advertised to the wider Internet as those IPs are not the source nor
destination of any normal traffic.

 
> Each party trunks their data to the neutral location at their own cost.
> 
> Each party plugs into a common network switch. GigE or 10GigE or something
> that works for all parties. You might charge more for a 10GigE connection
> then for a GigE connection but basically all parties pay based on
> what type of port they connect to and how many of these connections they
> have at the exchange.

I don't know of any that don't charge differently based on connection speed.


> Each party configures BGP to talk to the peering fabric.

Exchanges run route reflectors which means a single peering session can
receive the routes for all other networks connected to the reflector.

Exchanges with MLPA force use of the reflectors so all comers are equal.

Other exchanges allow both bilateral peering across the IX (for those who
practice "restricted" peering) as well as use of reflectors (for those who
practice "open" peering).


> Charge each party a nominal monthly levy to keep the Peering entity 
> running.
> 
> You can stop here if it is multi-lateral peering where all
> participants will exchange traffic with each other at no further cost.

This slightly muddles the concepts of "multi-lateral" i.e. who peers with
who and "settlement" i.e. what, if any, money changes hands.

 
> It gets more complicated if they want to be picky about which people
> they will peer with at the peering exchange (bi-lateral peering) or they
> expect some form of compensation if they put more traffic into the
> exchange then they take out.

The lines get really blurry at this point but the key defining factors are:

- what routes are exchanged

- what settlement is involved

In theory, "peering" is the mutual exchange of their own and their
customer's routes where both parties cover their own costs and no money is
exchanged.

In practice, "peering" is given many different qualifiers where either, or
both, of the above parameters are adjusted to suit the needs of the two
networks.

cheers
Marty