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I have a /96 block of IPV6 addresses and i'm wondering how i could some how find the next address (Since ipv6 addresses can contain numbers and letters). I know the first address could be in numbers but i've yet to find out how i could really find in some kind of order for that amount of addresses

E.G: What technique could i use to make sure i'll actually be able to use all of the addresses

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up vote 5 down vote accepted

It isn't letters as such, it is hexadecimal numbers, after 9, 10 is simply represented as A, 11 as B and so on until 15 as F.

So, the easiest thing you can do to learn/understand hexadecimal is to use calculator, switch to Advanced/Programmers mode, then you can click on the "HEX" button. This will allow you to go through the numbers -

Type 1+ =, then keep pressing on the = in order to go up by one. alt text

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I'm using a mac :S – Daniel Sep 30 '10 at 13:22
On the Mac, Open the Calculator application and choose View : Programmer. – Chris Nava Sep 30 '10 at 13:27
Theres no hex option there though? – Daniel Sep 30 '10 at 13:30
Apple do not support hexadecimal. They believed it too be too complex for ordinary users and prone to buffer overflow issues. Hence they use iAddress type notation for IPv6. Of course you must purchase an additional developer licence to use iAddresses and can only assign them from a Mac computer. Further more iAddresses are incompatible with ordinary IPv6 addresses. – PP. Sep 30 '10 at 13:57
@PP LOL - @Daniel Here is an online one - is just an example from a quick Google - I can't comment on MAC but there must be a better calculator you can download. – William Hilsum Sep 30 '10 at 14:00

The "numbers and letters" are actually hexadecimal numbers, so you have the following:

0 1 2 3 4 5 6 7 8 9 A B C D E F

which count from 0 to 15.

So if you had the "number" 99 the next value in the sequence would be 9A.

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The math is (2^(128-cidr))-2 which in you case is (2^32)-2 (4,294,967,294). So the host number portion of the address looks like:

   Integer   Hex
          1 0000:0001
          2 0000:0002
          3 0000:0003
          4 0000:0004
          5 0000:0005
          6 0000:0006
          7 0000:0007
          8 0000:0008
          9 0000:0009
         10 0000:000a
         11 0000:000b
         12 0000:000c
         13 0000:000d
         14 0000:000e
         15 0000:000f
         16 0000:0010
         17 0000:0011
         18 0000:0012
         19 0000:0013
         20 0000:0014
         21 0000:0015
         22 0000:0016
         23 0000:0017
         24 0000:0018
         25 0000:0019
         26 0000:001a
         27 0000:001b
         28 0000:001c
         29 0000:001d
         30 0000:001e
         31 0000:001f
         32 0000:0020
         33 0000:0021


 4294967294 ffff:fffe
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