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Comment Re:Everyone needs an address so you can be tracked (Score 1) 435

Port numbers is only useful and needed if you are dealing with carrier NAT. That is NAT performed by the ISP, such that multiple customers share the same ISP. This happens to be somewhat common with apartment networks.

If RIAA/MPAA records the address 2001:db8:a55:beef::2af6 only the "2001:db8:a55:beef" part is actually useful. The remaining part of the address will typically be a randomized privacy extension address. They are therefore still unable to prove which machine was used to download the content.

If you are one of the persons that want to use easy to remember addresses, you can still use privacy extensions. With IPv6 it is normal to have many address on each computer. You can have your easy to remember address (2001:db8:a55::2) that you use for ingoing connections. And the machine will prefer the random privacy extension address for outgoing connections (2001:db8:a55::9b43:82dd:2239:10bc - right now but in an hour it will be completely different).

Comment Re:Where's IPv6 then? (Score 1) 435

There is also some big sites that are available:

baldur@ballerup1:~$ for i in; do ping6 -c1 -n $i | grep bytes; done
PING 56 data bytes
64 bytes from 2a00:1450:4005:801::1000: icmp_seq=1 ttl=50 time=28.8 ms
PING 56 data bytes
64 bytes from 2a03:2880:20:4f06:face:b00c:0:1: icmp_seq=1 ttl=43 time=191 ms
PING 56 data bytes
64 bytes from 2a01:578:3::36e4:ea94: icmp_seq=1 ttl=46 time=38.0 ms
PING 56 data bytes
64 bytes from 2a02:26f0:103:186::22df: icmp_seq=1 ttl=54 time=22.3 ms
PING 56 data bytes
64 bytes from 2400:cb00:2048:1::c629:d59d: icmp_seq=1 ttl=57 time=10.6 ms
PING 56 data bytes
64 bytes from 2001:4801:1221:101:1c10:0:f5:116: icmp_seq=1 ttl=43 time=127 ms
PING 56 data bytes
64 bytes from 2620:0:862:ed1a::1: icmp_seq=1 ttl=52 time=20.7 ms

The CDNs in there means that you will get some content over IPv6 even from sites that are not IPv6 enabled as such.

Comment Re:the circle of strife. (Score 1) 435

IPv6 Neighbour Discovery protocol (ND) is the protocol used by IPv6 hosts to find each other. It is the IPv6 equivalent of ARP. And ND is based on multicast. Without multicast, nothing would work with IPv6.

An IPv4 host needs to use broadcast ARP packets to every host on the same network. This was fixed in IPv6, so each host uses the last 32 bits of its address as a multicast group. When you need to contact someone, you will take the last 32 bits of his address and then multicast your ND packets to that multicast group. That way only hosts that share the same last 32 bits will receive the ND packet. This dramatically reduces the amount of broadcast/multicast chatter received by each host.

The downside is that it only works on networks with MLD enabled switches. That is very rare. Without MLD the system will fall back to broadcast.

But just to point out that you are wrong to believe that multicast is experimental when in fact it was baked in from the very start.

Comment Re:Everyone needs an address so you can be tracked (Score 1) 435

You need to read up on IPv6 privacy extensions:

Your computer will generate a random IPv6 address and change that random address at regular intervals (typically a few hours before it changes). Therefore they will be unable to track the exact computer, because there is no way to know which computer had that random address at the time.

They will get you anyway due to cookies and device fingerprinting, but that is no different than the situation with IPv4 and NAT.

Also with carrier NAT ISPs in most countries are by law required to record the port numbers assigned to each user. Your IP might be shared with multiple other users, but as long they also recorded the port number, they will be able to find the user. RIAA and MPAA knows this - I get a ton of email from them every day complaining about users that download their stuff with Bittorrent and every complaint includes port numbers.

Comment Re:Move to the latest version? (Score 1) 435

Try "Network Prefix Translation" instead:

"This document describes a stateless, transport-agnostic IPv6-to-IPv6
      Network Prefix Translation (NPTv6) function that provides the
      address-independence benefit associated with IPv4-to-IPv4 NAT
      (NAPT44) and provides a 1:1 relationship between addresses in the
      "inside" and "outside" prefixes, preserving end-to-end reachability
      at the network layer."

Although personally I believe it is seldom needed. In practice a IPv6 home network can renumber every device within 30 seconds of the ISP changing the prefix on you. That is less time than it takes for your CPE router to reboot.

Comment Re:Move to the latest version? (Score 1) 435

Nope, all three protocols will work fine with any prefix size. Only SLAAC need a /64 prefix

If you did a /120 you would use RA to tell your network about it. You would then need to set the managed config flag, so your devices can use DHCPv6 to acquire an address. After getting an address through DHCPv6 the devices will use the DAD process to check that the address is unused. And they will use ND to be able to communicate with other devices.

Comment Re:Move to the latest version? (Score 1) 435

The majority of internet service providers will give you a /48 prefix. Meaning that you decide what to do with the remaining 80 bits. If you make them all zero, your IPv6 address can indeed be shorter than the typical IPv4.


2001:db8:123:: (that would be your router)
2001:db8:123::2 (that would be your web server or whatever).
2001:db8:123::3 (that would be your mail server or whatever).

Compare to: (that would be your router - and also your web/mail server because it is all you got).

Comment Re:Three years after Europe ran out? (Score 1) 435

Blocks less than a /24 are not routable on the Internet. For some reason it was RIPE that tested that with a loaned block from ARIN.

One can hope that ARIN will recognize the need to be able to route this on the internet as sufficient reason to get a /24 instead of a /28.

There is one other difference to the RIPE policy and that is the IPv6 requirement. There is no such requirement by RIPE. You will get your /22 from RIPE and you can continue to ignore IPv6 and just use it with carrier NAT or whatever. RIPE will ask you to take an IPv6 assignment as well, but they do not ask if you are going to use it for anything.

Comment Re:Move to the latest version? (Score 1) 435

You are wrong. My router does have DHCPv6 and so does every OS (Linux, Mac and Windows) on my network.

You will find that basically 100% of the new generation routers (those with 802.11ac radios) come with full fledged IPv6 support these days. Including DHCPv6 support.

As to the ISP that seems to depend entirely on what country you live in. Some countries have very high penetration now. The rest of the world will follow.

Comment Re:Move to the latest version? (Score 1) 435

They wont because my ISP makes static allocations to every customer. But if you have another ISP with a poor policy, then you can use a private range such as fd00::/64 for your internal network.

fd00::2 is shorter than if we are still at that...

Yes you are supposed to put in something random in the fd00 style address. But nothing stops you from ignoring that. It is just so that your VPN to your employer does not collide unnecessary with your home network, but if both of you choose to use the same range, you are no worse off than if the same thing happened on IPv4.

For the average customer this is no issue however. They are in don't care about IP-addresses boat. If the ISP changes your prefix, your internal network will just renumber too and nobody notices.

Comment Re:Move to the latest version? (Score 1) 435

Actually my IPv6 address is:


Notice how it is _exactly_ the length of your proposal? I also happen to be able to remember it...

Ok, it is the address of my router, from where I can do port forwards etc, just like we used to do. So if you ssh into that, you will get to my server.

My other devices have longer addresses. Such as 2a00:7660:349::2. Yes there is a thing called DHCPv6 that allows one to assign short addresses to devices.

And because the ISP only controls the first 48 bits of the address, every device of mine gets to have an IP address and I was the one that decided the parts that might need to be remembered (the "2" from before).

It is true that most people will just let their network do auto configuration, which will then result in random and long addresses. That is because these days people generally do not care about IP-addresses. But it is your option - you can get it nice and clean if you are one of the few that cares.

Comment Re:America! F-Yeah! (Score 2) 435

You found enough /8 blocks to distribute one or two to each region. It would be gone within the week.

APNIC and RIPE have been out for years now and ARIN is building up a waiting list. The demand did not just stop - there is a huge unfilled demand there that will soak up any stray addresses you can find.

But the real problem is that there is no legal framework to force these companies to stop using the addresses. How much worth is an IP address that can not be used by an Apple device?

Comment Re:Its all in the taxes and incentives. (Score 1) 211

Each generator is constantly trying to run a little faster than the grid. This result in a current from the generator. If the generator only matched the grid exactly, there would be no current which means there would be no power generated.

The grid frequency will in fact change according to load. Look it up. If the grid is overloaded, the frequency drops. This happens because the voltage difference between the generator and the grid is just another way to view the fact that the generator is a bit a head. A bigger voltage difference means the generator is further ahead. A bigger voltage difference also means more current and more power is being drawn out of the generator, which it can not hold up. Therefore the generator will slow down until the voltage difference between the grid and the generator matches the power rating of the generator.

The reverse is also true. If there is less demand than power generated, the voltage will rise and the generators will start skipping further ahead. The frequency goes up.

Most generators need the grid to pace them correctly. They can not run without the grid. This creates big trouble when the grid crashes and none of the powerplants are able to start up isolated. Usually they have a few generators that have the special ability to boot the grid.

Large generators have inertia. They will not change frequency quickly. This is important to keep the grid stable. Small generators, such as those in windmills, do not have this property. This means you can not run a grid on windmills alone. In some parts of Germany this is sometimes a big problem.

Comment Re: wft ever dude! (Score 1) 215

Network, gateway and broadcast are still IP addresses so the company does indeed own 512 addresses.

Second, it is not true that you can not use 3 IP addresses. The most obvious is the gateway address - can the computer doing the routing not also run a web server? Does in fact not most home routers run various services, including a web server, dhcp client, NAT etc?

The subnet would be routed and usually the IP address used for routing would be provided by the IP transit company. As a routed subnet there is nothing that forces a particular subnetting scheme. They could deploy it as a big /23 subnet. Or as a bunch of /30 subnets, allowing only 128 "usable" IP addresses.. But they could equally also deploy /32 addresses and this technique would allow you to use all 512 IP addresses for hosts. Or it could be used as a NAT pool, again allowing you to use all addresses including the first and last address in the series.

As to how you deploy /32 addresses you can do that by DHCP or manually - on Linux eg:

# add the /32 address
ip addr add dev eth0
# add a host route for the IP that will be used for gateway
ip route add dev eth0
# add default gateway route
ip route add default via

Notice that you can use a completely different subnet for gateway, such as

"It's like deja vu all over again." -- Yogi Berra