[c-nsp] DS1 provisioning using IP Unnumbered vs /30s

[Gert Doering]

Hi,

On Thu, Feb 05, 2009 at 06:01:09PM -0600, Justin Shore wrote:
> I'm curious to see what everyone's take is on handling the addressing of 
> customer-facing DS1s.  

We run all our customers "ip unnumbered", whether it's E1/E3 or DSL
customers.  Since the first 64 kbit ISDN leased line...

Exception:
  - customers on ethernet circuits
  - customers that require dynamic routing
  - customers with multiple circuits and failover
    (to be able to monitor the links independent of the customer service IPs)

QoS, ACLs, etc. are tacked to the physical interface (or virtual, in
case of DSL), never to the loopback.

> I'm actually looking at options to restrict bcasts 
> between IP unnumbered serial interfaces too.  We need to allow direct
> access between the sites but not bcast.

Where should broadcasts come from...?  There is nothing in your router
that would turn "all serial links on this box" into "a big broadcast
domain", except if you configure a bridge group (which is not a good
plan).

> I know that IP unnumbered works in general; I'm just wondering if anyone 
> has already done it in production and ran into problems?  My goal is to 
> not waste IP space on network and bcast addresses where possible.  

Go for IPv6 :-)

gert
-- 
USENET is *not* the non-clickable part of WWW!
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Gert Doering - Munich, Germany                             gert at greenie.muc.de
fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de
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