Re: Start accepting longer prefixes as IPv4 depletes?
From nanog-bounces+bonomi=mail.r-bonomi.com@nanog.org Wed Dec 8 15:36:44 2010 Date: Wed, 08 Dec 2010 15:34:47 -0600 From: Jack Bates <jbates@brightok.net> To: David Conrad <drc@virtualized.org> Subject: Re: Start accepting longer prefixes as IPv4 depletes? Cc: NANOG list <nanog@nanog.org>
On 12/8/2010 3:12 PM, David Conrad wrote:
Cameron,
On Dec 8, 2010, at 12:01 PM, Cameron Byrne wrote:
I believe a lot of folks think the routing paths should be tightly coupled with the physical topology.
The downside, of course, being that if you change your location within the physical topology, you have to renumber. Enterprises have already voted with their feet that this isn't acceptable with IPv4 and they'll no doubt do the same with IPv6.
In a mature IPv6 world, that is sane, i am not sure what the real value of LISP is.
Sanity is in the eye of the beholder. The advantage a LISP(-like) scheme provides is a way of separating location from identity, allowing for arbitrary topology change (and complexity in the form of multi-homing) without affecting the identities of the systems on the network. Changing providers or multi-homing would thus not result in a renumbering event or pushing yet another prefix into the DFZ.
I think the issue, and correct me if I'm wrong, is that LISP does not address issues of traffic engineering? A lot of the additional routes in DFZ are there specifically to handle traffic engineering.
The primary thing that a LISP-like approach accomplishes is the 'de-coupling" of infrastructure and leaf networks. You can mess with either one, w/o having any effect on the other.
On Dec 10, 2010, at 12:30 , Robert Bonomi wrote:
From nanog-bounces+bonomi=mail.r-bonomi.com@nanog.org Wed Dec 8 15:36:44 2010 Date: Wed, 08 Dec 2010 15:34:47 -0600 From: Jack Bates <jbates@brightok.net> To: David Conrad <drc@virtualized.org> Subject: Re: Start accepting longer prefixes as IPv4 depletes? Cc: NANOG list <nanog@nanog.org>
On 12/8/2010 3:12 PM, David Conrad wrote:
Cameron,
On Dec 8, 2010, at 12:01 PM, Cameron Byrne wrote:
I believe a lot of folks think the routing paths should be tightly coupled with the physical topology.
The downside, of course, being that if you change your location within the physical topology, you have to renumber. Enterprises have already voted with their feet that this isn't acceptable with IPv4 and they'll no doubt do the same with IPv6.
In a mature IPv6 world, that is sane, i am not sure what the real value of LISP is.
Sanity is in the eye of the beholder. The advantage a LISP(-like) scheme provides is a way of separating location from identity, allowing for arbitrary topology change (and complexity in the form of multi-homing) without affecting the identities of the systems on the network. Changing providers or multi-homing would thus not result in a renumbering event or pushing yet another prefix into the DFZ.
I think the issue, and correct me if I'm wrong, is that LISP does not address issues of traffic engineering? A lot of the additional routes in DFZ are there specifically to handle traffic engineering.
LISP has TE properties based on priority of the locators and weight (for load balancing). You can read: http://inl.info.ucl.ac.be/system/files/inm08.pdf Luigi
The primary thing that a LISP-like approach accomplishes is the 'de-coupling" of infrastructure and leaf networks. You can mess with either one, w/o having any effect on the other.
participants (2)
-
Luigi Iannone -
Robert Bonomi