CIX routing service (was Re: AGIS/DIGEX)

Tue Nov 5 22:57:55 UTC 1996

> > > [...]  Since Digex is at too few NAPs to peer with AGIS, and they
> > > are not at the CIX, we see no routes from them. 
> 
> CIX is taking new connections, either T1, PB-SMDS, or DEC-PAIX (FDDI or
> Ether).

Just a side thought about CIX's role in the Internet...

With peering requirements becoming too strict for new players, I see
two alternatives for getting good peering connectivity:

	- RA servers
		- semi-reliable registration-based database for routing
		  updates
		- lacks media sensing

	- CIX
		- on-the-fly trust-the-providers routing updates
		- media sensing through BGP peering sessions
		- router could overload

CIX started up long ago to "create a level playing field" (commercial
providers vs. ANS/NSFNET/AUP).  When everyone willingly peered with
everyone else at MAE's and NAPs, CIX was becoming a moot point (why
use CIX over a slow link when I can go direct via DS3/Router/Giga/-
Router/DS3?).  Now that the playing field isn't level anymore (big
fish refusing to peer with little fish), perhaps CIX has a new use -
simple peering at major exchange points.  Instead of having people all
try to peer with each other, a lengthy process and complex to manage),
why not have CIX put a router in any exchange point and say, "Here CIX
members, peer with this router and you'll get routing to every other
CIX member at the exchange point."  The "big ISPs" will still peer
with each other directly, even privately, but they have enough traffic
in between them to make it worthwhile.  New or small ISPs would be the
primary benefactors.

So you ask, "What about RA?"  I have nothing against it.  For new
providers, it's an excellent solution that gets them off the ground
peering.  I suspect though that some providers just don't like the
fact that the routing is decoupled from the L2 switching making
exchange point connectivity outages hard to detect/correct quickly.

Some would say that CIX gets saturated.  Yes, CIX-West was at one
time fatally saturated on incoming bit pipes (not necessarily CIX's
fault), but saturation can be reduced or eliminated by:
	- having multiple CIX routers - one set at every major
	  exchange point (no, there's no bacbone in between).
	- rate-limiting peers to a maximum of XX Mbps (ATM, yes;
	  possible on GigaSwitchs or FDDIs?).
	- detecting then encouraging peers with more than X Mbps of
	  traffic (on average) to offload traffic to direct peering
	  or other exchange points.
	- Using multiple iBGP routers at an exchange point.

Then again, it doesn't have to be CIX; it just seems natural since
they've been running CIX-West for oh-so-long.  A bunch of smart
BGP people can go out, get some money, buy the equipment, install it,
and have ISPs pay them for the service.

Would such a peering entity compete with ISPs?  I don't think so.
Routing at a peering point isn't their business - transiting customers
to "the Internet" reliably and quickly is.  ISPs would be the customers
of the "enhanced peering service".

I don't think this is really a new idea, nor really my concern, but
I see two of my service providers struggling to get new peering and
think, "There's got to be a better way."

... just something to think about.

--
Eric Ziegast
Looking in from the edge