Subnet Size for BGP peers.

Doug McIntyre merlyn at
Thu Jul 30 20:22:24 UTC 2009

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). 

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