Subnet Size for BGP peers.

Roy r.engehausen at
Thu Jul 30 21:01:36 UTC 2009

Doug McIntyre wrote:
> On Thu, Jul 30, 2009 at 12:22:27AM -0400, Barton F Bruce wrote:
>> So what is wrong with a /31? We use /30s but if you are short on IP space, 
>> look at using /31 rather than /30 links. Cuts your space usage in half.
> /31's are only defined for point-to-point links. 
> Ethernet isn't considered PtP in general..
> Many devices won't accept a /31 on anything but a PtP WAN media type link.
> (or not at all). 
Since it isn't PtP, one also has to allow the customer to connect 
multiple devices.

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