IPV6 Training Books

Owen DeLong owen at delong.com
Mon Apr 4 20:52:22 CDT 2011


More ideally, you give every end site a /48 if they want more than one network.

Owen

On Apr 4, 2011, at 5:59 PM, Mark Andrews wrote:

> 
> In message <690D7D20D2507C44BA8066926B2009890867FA at ES1002.ic-sa.com>, Michael R
> uiz writes:
>> Hello All,
>> 
>>                I am looking for some good reading material to get a better=
>> understanding of IPV6.  I know how to convert HEX into decimal format.  Wh=
>> at I am looking for is how to under the CIDR notation and break them out in=
>> to subnets.   Thank you in advance.
> 
> If you think in hex its straight forward to do CIDR in IPv6.  There
> are only three groupings on a non nibble boundaries.  You also
> display the entire 128 bits with the least significant bits set to
> zero.  The :: notation is used to shorten the displayed address.
> 
> e.g for a /57, /58 and /59 with leading bits of 2001:23bc:fe8d:b200::/56
> you would have.
> 
> /57	{0,1,2,3,4,5,6,7} {8,9,a,b,c,d,e,f}
> 	2001:23bc:fe8d:b200::/57
> 	2001:23bc:fe8d:b280::/57
> /58	{0,1,2,3} {4,5,6,7} {8,9,a,b} {c,d,e,f}
> 	2001:23bc:fe8d:b200::/58
> 	2001:23bc:fe8d:b240::/58
> 	2001:23bc:fe8d:b280::/58
> 	2001:23bc:fe8d:b2c0::/58
> /59	{0,1} {2,3} {4,5} {6,7} {8,9} {a,b} {c,d} {e,f}
> 	2001:23bc:fe8d:b200::/59
> 	2001:23bc:fe8d:b220::/59
> 	2001:23bc:fe8d:b240::/59
> 	2001:23bc:fe8d:b260::/59
> 	2001:23bc:fe8d:b280::/59
> 	2001:23bc:fe8d:b2a0::/59
> 	2001:23bc:fe8d:b2c0::/59
> 	2001:23bc:fe8d:b2e0::/59
> 
> Note the last nibble before the :: is 0 and is there so that the
> final bits are all zeros.  The following all represent the same
> cidr block.
> 
> 	2001:23bc:fe8d:b2e0::/59
> 	2001:23bc:fe8d:b2e0:0000:0000:0000:0000/59
> 	2001:23bc:fe8d:b2e0:0:0:0:0/59
> 
> Normally you just assign /64 subnets and delegate address blocks
> on nibble boundaries to end customers, e.g. /48, /52, /56 or /60.
> This means that end customers don't need do deal with cidr block
> if they don't want to.  They can just route individual /64.
> 
>> MAR.
>> 
> -- 
> Mark Andrews, ISC
> 1 Seymour St., Dundas Valley, NSW 2117, Australia
> PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org





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