5 ms·
> Can someone explain why it's ambiguous? Because you don’t know how many zeroes are on each side around the 0001 in the middle. It can be 2000:0000:1:0000:00
by boob 10mo ago
> Can someone explain why it's ambiguous?
Because you don’t know how many zeroes are on each side around the 0001 in the middle.
It can be 2000:0000:1:0000:0000:0000:0000:1 or 2000:0000:0000:0000:0000:1:0000:1 etc.
- koakuma-chan 10mo agoThis shortcut system of ipv6 only makes it worse. It's too hard to remember how it works.
- karlshea 10mo ago":: is all zeros" is too hard??
- koakuma-chan 10mo agoIt's not just ":: is all zeroes"
- ninkendo 10mo ago… such as?
- DaSHacka 10mo agohttps://news.ycombinator.com/item?id=46338674 https://news.ycombinator.com/item?id=46338674
- WarOnPrivacy 10mo agoI am not clear what your point is. The parent's point stands. A double colon only represents zeros (that were compressed and are not displayed). Your link does not show different addresses from a valid compression, it shows different addresses from an invalid compression. The link examples what we don't do. Conversely, if we compress the expanded addresses in your link, we will get 2 different compressed addresses.
- Dylan16807 10mo agoThat's a post about invalid things that are not IPv6 addresses. In IPv6 addresses, :: is all zeroes and there's no ambiguity.
- webignition 10mo agoHow many zeros?
- db48x 10mo agoExactly enough to fill out the address, which is always the same length. BTW, IPv4 does basically the same thing. The address 127.1 is equivalent to 127.0.0.1.
- integralid 10mo agoNot really the same, the mechanics are different and this particular behaviour is pretty much an accident, not abbreviation. In IPv4 you also have 127.257 equal to 127.0.1.1, 123456789 equal to 7.91.205.21, and 010.010.010.010 is a well-know DNS server. This notation is also rejected by most implementations.
- jstanley 10mo agoHowever many are left. In what circumstances do you care?
- kstrauser 10mo agoHowever many it takes to make the whole A::B number exactly 128 bits long.
- paulddraper 10mo ago“Enough”
- icedchai 10mo agoIs it really hard to remember? A hint is in the syntax itself. What's in between the two colons '::'? Nothing. In other words, all zeros. IPv4 also has a similar, though rarely documented or utilized, shortcut system. Try `ping 1.1` for example. It expands to 1.0.0.1.