nanog mailing list archives
Re: Buying IP Bandwidth Across a Peering Exchange
From: Bill Woodcock <woody () pch net>
Date: Tue, 25 Nov 2014 10:56:06 -0800
On Nov 25, 2014, at 10:47 AM, Colton Conor <colton.conor () gmail com> wrote:
I know typically peering exchanges are made for peering traffic between providers, but can you buy IP transit from a provider on an exchange? An example, buy a 10G port on an exchange, peer 5Gbps of traffic with multiple providers on the exchange, and buy 5Gbps of IP transit from others on the exchange?
Some IXPs have a rule that explicitly disallows this, others encourage it, most don’t care. I don’t know of any that have a mechanism to enforce a rule prohibiting it. PCH’s guidance in the IXP formation process is to avoid creating rules which are, practically, unenforceable. So we generally counsel IXPs against having a rule precluding transit across the switch fabric. That said, a crossconnect is a _much better idea_.
Some might ask why not get a cross connect to the provider. It is cheaper to buy an port on the exchange (which includes the cross connect to the exchange) than buy multiple cross connects. Plus we are planning on getting a wave to the exchange, and not having any physical routers or switches at the datacenter where the exchange/wave terminates at. Is this possible?
Yes, it’s possible, but what you describe is a pretty fragile setup. Lots of common points of failure between peering and transit; places where screwing one up would screw both up. If all of this is really tangential to whatever you’re doing, and you don’t mind looking a little out-of-step with best practices, and you don’t mind it all being down at once, any time anything breaks, then it may be a reasonable economy. If you’re planning on actually depending on it, you need to do better engineering, and either spend more money, or allocate your money more conservatively. Doing everything the cheapest possible way, regardless of the fragility or complexity, is very short-sighted, and is unlikely to be an economy in the long run. -Bill
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Current thread:
- Buying IP Bandwidth Across a Peering Exchange Colton Conor (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Randy Epstein (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Nick Hilliard (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Chris Rogers (Nov 25)
- RE: Buying IP Bandwidth Across a Peering Exchange Tony Wicks (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Chris Rogers (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Bill Woodcock (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Bob Evans (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Mark Tinka (Nov 26)
- Re: Buying IP Bandwidth Across a Peering Exchange Bob Evans (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Ammar Zuberi (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Colton Conor (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Faisal Imtiaz (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Justin Wilson (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Mark Tinka (Nov 26)
- Re: Buying IP Bandwidth Across a Peering Exchange Colton Conor (Nov 25)
- RE: Buying IP Bandwidth Across a Peering Exchange Eric Van Tol (Nov 25)
- Re: Buying IP Bandwidth Across a Peering Exchange Mark Tinka (Nov 26)
- Re: Buying IP Bandwidth Across a Peering Exchange Ammar Zuberi (Nov 26)
- Re: Buying IP Bandwidth Across a Peering Exchange Mark Tinka (Nov 26)