[186247] in North American Network Operators' Group
Re: DHCPv6 PD & Routing Questions
daemon@ATHENA.MIT.EDU (Owen DeLong)
Sun Dec 6 19:07:31 2015
X-Original-To: nanog@nanog.org
From: Owen DeLong <owen@delong.com>
In-Reply-To: <20151206230347.GA3528@panix.com>
Date: Sun, 6 Dec 2015 16:05:23 -0800
To: Brett Frankenberger <rbf+nanog@panix.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
> On Dec 6, 2015, at 15:03 , Brett Frankenberger <rbf+nanog@panix.com> =
wrote:
>=20
> On Sun, Dec 06, 2015 at 02:20:36PM -0800, Owen DeLong wrote:
>>=20
>> As an alternative worth considering, it could do this with BGP =
instead of OSPF.
>>=20
>> There=E2=80=99s nothing mythical or magical about BGP. A CPE =
autoconfiguring
>> itself to advertise the prefix(es) it has received from upstream
>> DHCPv6 server(s) to it=E2=80=99s neighbors is not rocket science. In =
fact,
>> this would mean that the CPE could also accept a default route via
>> the same BGP session and it could even be used to enable automatic
>> failover for mulihomed dynamically addressed sites.
>>=20
>> Sure, this requires modifying the CPE, but not in a particularly huge
>> way and it provides a much cleaner and more scaleable solution for
>> the ISP side of the equation than OSPF.
>>=20
>> Most current implementations use RIPv2, but we all know just how icky
>> that is.
>=20
> How do you secure that? Or do you just assume no one will announce
> someone else's prefix? (I can think of ways to secure it, of course,
> but none of the approaches for having the DHCP server configure some
> sort of prefix access control seem to me to be any better or easier
> than having the DCHP server configure a static route).
>=20
> This isn't a problem I face, but if it were, I think I'd solve it by
> having the DHCP server inject the route via BGP with an appropriate
> next-hop.
A perfectly valid alternative=E2=80=A6 However, lots of people seem =
determined to use
a routing protocol from the CPE. Given that constraint, I was looking at =
the options available
and trying to pick the most reasonable among them.
Note: Your concern is equally applicable to RIPv2 and OSPF as it is to =
BGP.
Owen
