IPv6 addressing

[S891]

I am planning for IPv6 address assignment for my enterprise network. I have read several documents and posts. I want to have some correlation between IPv4 and IPv6 addresses. So far example IPv4 address 88.72.52.0/24 will map to 2abc:def:72:52::/64.  

My questions are following:

1. Is this a reasonable approach? 

2. Is there any drawback in mapping ipv4 to ipv6?

3. Is there any alternate better approach?

thanks

[johnd2310]

Hi,

The following is my personal opinion:

1. Is a reasonable approach if your network is small.
2. In large networks with a lot of variable length subnet masks, there could be issues with overlapping prefixes e.g. if you have user subnets 88.72.52.0/26 and 88.72.52.64/26 then 2abc:def:72:52::/64 won't work
3. You could assign addresses based on  topology, organisational boundaries or services boundaries

The following resources are a good reference for IPv6 address planning:

https://www.cisco.com/c/dam/en/us/td/docs/solutions/CVD/Aug2013/CVD-IPv6AddressingWhitePaper-AUG13.pdf

http://www.ipv6forum.com/dl/presentations/IPv6-addressing-plan-howto.pdf

Thanks

John

[Sergey Lisitsin]

Fawad, I think many people find it easier to have some sort of correlation between IPv4 and IPv6 addresses in their network. However, I would advise against that. Firstly, if your IPv4 addressing scheme is not ideal, like having some sub-optimal subnetting or some weird scheme, you would have to replicate that mess into brand new shiny IPv6 network for no reason. Secondly, as already mentioned, if you have VLSM in your IPv4 network, this correlation will break anyway, because in IPv6 standard you only need /64s, which makes it simple and predictable.  So if at first your IPv6 addressing will seem alien, after a while you will get used to it and the benefits of having a well-structured IP address space will definitely outweigh the initial discomfort of not having familiar numbers.

[Vishnu Vardhan S]

Firstly you can use below link to convert it. 

https://www.ultratools.com/tools/ipv4toipv6

How it works is very simple :

Of you should you have your network portion with you and we are going to care about only the host portion of the IPV6.

So for example our IP is 10.0.0.1 so convert it into binary

00001010 0000000 0000000 00000001

Split into 4 digits. 

0000 1010 0000 0000 0000 0000 0000 0001

convert into hexa values

0        A    0           0         0       0     0       1

Combine 4 values.

0A00:0001 = A00 :1

We found the last 2 portions of IPv6 out of 8 

so finally we will get. 

0000:0000:0000:0000:0000:FFFF:A00:1

By,

@Networkchef

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