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Bits Help - We've Run out of IP Addresses!

Discussion in 'Article Discussion' started by arcticstoat, 3 Jun 2011.

  1. Vadoff

    Vadoff What's a Dremel?

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    I see. I already know that hexadecimals offer more numbers than decimal, I'm just wondering why they can't keep it in decimal since it's much easier to remember, read/write down. Even adding 3 additional digits should give us plenty of IPs (1000 times more than we have currently, 1,000,000 times more with 6); I don't understand the need for hexadecimals since it's not like we need that absurd undecillion amount of IPs anyways.
     
  2. Zoon

    Zoon Hunting Wabbits since the 80s

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    Yes they are. All you have to do is request some from your ISP giving a justification for it and you can have them. Some ISPs will charge an administrative fee for doing this some won't.
    Not sure if you're being facetious - if you are, then :lol: - if not, then its to do with binary maths. An IP address in its current form is a 32bit number - 4 x 8bit octets - and there's only space in the IP packet for an IP address of that size. So that means you have to bin off large parts of the IP protocol anyway to make it accept the IP address. If you're gonna do that you may as well increase to 128bit to give a ridiculous amount of IP addresses. So they did.
     
  3. Woodstock

    Woodstock So Say We All

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    As said by zoof, its based on binary math 32bit = 2 ^ 32 = 4294967296, 128bit = 2 ^ 128 = 34028236692093846346337460743176811456. Additionaly decimal numbers suck for computers. A binary(base 2) number takes 1 bit to represent, an ocatal (base 8) take 3, hex (base 16) takes 4 and decimal (base 10) takes 3 (cant have part bits, there binary values).

    Decimal imho was a bad decision for ipv4 address. Additionaly the reason to grow ip address by an additional 2 powers of two (or even 1) is based on storing the number in cache and registers, and being to apply instructions effiecently to them.

    The seperators exist for two main reasons, human readability and the ability to use bit masks to seperate the network and host portion (routing).

    No its not backwards compatable, he said that was the route not taken. An ipv6 machine cannot talk to an ipv4 machine (and vice versor) nativly. You need some sort of 4 to 6 tunnel, which I suspect most commodity routers will do in the future. You either need a tunnel or to run a dual stack machine to communicate across versions.
     
  4. tehBoris

    tehBoris What's a Dremel?

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    255 = 0xFF = 0377

    Number representation used is fairly irrelevant.

    IPv6 is backwards compatible with IPv4. It has the whole IPv4 range reserved for this purpose. You may or may not need to use to gateway to contact a device on an IPv4 network, this is contextual. If you try to go to a IPv6 address that is in the IPv4 reservation your OS should automatically know to try and send that request out as IPv4 if it is on the correct subnet or has a route to it. If it does not have IPv4 configured or does not have a route for the requested address, it will send the request to it's default IPv6 gateway hoping that this can take care of it. In all likely hood, this is likely to never bother any one.
     
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