Using /126 for IPv6 router links

Ryan Harden hardenrm at
Mon Jan 25 19:23:42 UTC 2010

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Our numbering plan is this:

1) Autoconfigured hosts possible? /64
2) Autoconfigured hosts not-possible, we control both sides? /126
3) Autoconfigured hosts not-possible, we DON'T control both sides? /64
4) Loopback? /128

Within our /48 we've carved it into (4) /50s.
* First, Infrastructure. This makes ACLs cake.
** Within this /50 are smaller allocations for /126s and /128s and /64s.
* Second, User Subnets (16k /64s available)
** All non-infrastructure subnets are assigned from this pool.
* Third, Reserved.
* Fourth, Reserved.

We believe this plan gives us the most flexibility in the future. We
made these choices based upon what works the best for us and our tools
and not to conserve addresses. Using a single /64 ACL to permit/deny
traffic to all ptp at the border was extremely attractive, etc.

- -- 
Ryan M. Harden, BS, KC9IHX		Office: 217-265-5192
CITES - Network Engineering		Cell:  	217-689-1363
2130 Digital Computer Lab		Fax:    217-244-7089
1304 W. Springfield	 		email:  hardenrm at
Urbana, IL  61801 			

      University of Illinois at Urbana/Champaign - AS38
	   University of Illinois - ICCN - AS40387
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