So, if you work at an Internet service provider, manage Internet-connected servers, or develop software or hardware — yes, you should care about IPv6! More Efficient Routing — IPv6 reduces the size of routing tables and makes routing more efficient and hierarchical. By , the last remaining blocks of IPv4 addresses were allocated. With IPv5 using the same bit addressing, it would have suffered from the same limitation.
So, IPv5 was abandoned before ever becoming a standard, and the world moved on to IPv6. IPv6 stands for the Internet Protocol, version 6. It is true that IPv6 will change addressing on the Internet. In fact, IPv6 actually has features that are designed to foil these sorts of plans. IPv6 uses bit addresses, allowing 3. This is equal to trillion trillion trillion IP addresses. Will IPv6 addresses run out eventually?
In practical terms, no. This will be more than sufficient to support trillions of Internet devices for the forseeable future. The prefix-length in IPv6 is the equivalent of the subnet mask in IPv4. However, rather than being expressed in four octets like it is in IPv4, it is expressed as an integer between 1 through So your wifi and cellular will have two different ones.
Link-local addresses are not routable off the link IPv6 subnet. Examples: FEDC:BAFEDC:BA 39 characters CA 25 characters The second, or zero suppressed, form allows "::" to indicate multiple groups of suppressed zeroes, hence: CA may be represented as CA a saving of just 5 characters from this typical address form, and still leaving 21 characters.
In other cases the saving is more dramatic, in the extreme case, the address: that is, the unspecified address, can be written as :: This is just 2 characters, which is a considerable saving. However such cases will rarely be encountered. These can be considerably longer than the longest normal IPv6 representation, and will eventually be phased out.
Consequently they will not be considered further here. Why 85? As there are just 94 ASCII characters excluding control characters, space, and del base 94 is the largest reasonable value that can be used.
Even if space were allowed, base 95 would still require 20 characters. Thus, any value between 85 and 94 inclusive could reasonably be chosen. Selecting 85 allows the use of the smallest possible subset of the ASCII characters, enabling more characters to be retained for other uses, eg, to delimit the address. The Character Set The character set to encode the 85 base85 digits, is defined to be, in ascending order: '0'..
Refer - superuser. Show 5 more comments. Yury Yury 2, 2 2 gold badges 20 20 silver badges 24 24 bronze badges. So what is this 48 I see? Possibly incremented for struct alignment. Answered my own question: IPv6 addresses are normally written as eight groups of four hexadecimal digits, where each group is separated by a colon :.
So that's 39 characters max. However there's apparently a caveat, see stackoverflow. The maximum should therefore be 45 characters. The answer at stackoverflow. Sean F Sean F 3, 14 14 silver badges 24 24 bronze badges. True, but this is only link-local addresses, and you aren't going to see any of those once your website is running on the Internet and hopefully not even while developing it. This answer deserves more attention.
It's best to add 5 more characters than to debug such a weird issue for an hour, just to find out such exception. So, for people who want to know the true max amount of characters, this answer is the best of all. QMaster QMaster 3, 2 2 gold badges 37 37 silver badges 54 54 bronze badges. A slightly conflicted -1 conflicted because I've fallen into this trap before, and I guess this answer contains info relevant to some people who will be arriving on this page because nonetheless this clearly isn't an answer to the question asked.
Your mileage may vary. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How many characters can an IP address be? Ask Question. Asked 9 years, 9 months ago. Active 7 years ago. Viewed 26k times.
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