[113671] in North American Network Operators' Group
Re: IXP
daemon@ATHENA.MIT.EDU (Nathan Ward)
Sat Apr 18 00:35:33 2009
From: Nathan Ward <nanog@daork.net>
To: NANOG Off-topic Gripes <nanog@merit.edu>
In-Reply-To: <g3myaej02j.fsf@nsa.vix.com>
Date: Sat, 18 Apr 2009 16:35:17 +1200
Errors-To: nanog-bounces@nanog.org
On 18/04/2009, at 12:08 PM, Paul Vixie wrote:
> i should answer something said earlier: yes there's only 14 bits of
> tag and
> yes 2**14 is 4096. in the sparsest and most wasteful allocation
> scheme,
> tags would be assigned 7:7 so there'd be a max of 64 peers. it's more
> likely that tags would be assigned by increment, but it's still
> nowhere
> near enough for 300+ peers. however, well before 300 peers, there'd
> be
> enough staff and enough money to use something other than a switch
> in the
> middle, so that the "tagspace" would be per-port rather than global
> to the
> IXP. Q in Q is not how i'd build this... cisco and juniper both have
> hardware tunnelling capabilities that support this stuff... it just
> means
> as the IXP fabric grows it has to become router-based.
On Alcatel-Lucent 7x50 gear, VLAN IDs are only relevant to that local
port. If you want to build a "VLAN" that operates like it does on a
Cisco switch or something, you set up a tag on each port, and join the
tags together with a L2 switching service. The tag IDs can be
different on each port, or the same... it has no impact.
--
Nathan Ward
