6 ms·

I'm happy that my ISP gives me a /29 ipv4 block :). An example of a real world effect is one of the largest fibre ISPs in the U.K. They are the only provider a

by nvarsj 10y ago

I'm happy that my ISP gives me a /29 ipv4 block :). An example of a real world effect is one of the largest fibre ISPs in the U.K. They are the only provider afaik to assign users internal IPs, which is then NAT'd. This then gets NAT'd on the router again - double NAT, woohoo! :) I know they desperately tried to get enough public space for all their customers, but were unable to buy a large enough space for it, so were forced into this position. Interestingly, the U.K. has at least two /8 ranges that aren't even advertised on the public internet, owned by MoD (25/8) and Department of Work & Pensions (51/8). That's 32 million addresses unused as far as anyone can tell from the outside.

nmc 10y ago
Seriously? They assign internal addresses (10/8, 172.16/12, 192.168/16) to all customers? Are you able to name the ISP?
- knorker 10y ago
  Is it rare? I think BT's cheaper broadbands do this, for one.
  - tokenizerrr 10y ago
    I certainly have never encountered this, and would be really unhappy if my ISP pulled this stunt.
    - j3097736 10y ago
      Only the early players get the luxury of large IP pools, everyone else has had to resort to carrier-grade NAT. Fortunately some of those can un-NAT you if you ask politely.
  - vertex-four 10y ago
    BT does this unless you either have an Unlimited package or opt out through their website.
- the8472 10y ago
  That's fairly normal these days. The combination of ipv6 + cgnat for ipv4 (carried over the v6) is called DS-Lite[0]. ISPs in asian countries have been doing that for years now european and american ISPs have been ramping it up recently too. [0] https://tools.ietf.org/html/rfc6333 https://tools.ietf.org/html/rfc6333
  - userbinator 10y ago
    ISPs in asian countries have been doing that for years And they usually call it "web access" or something similar, never speaking of an "Internet connection". Which is what it is, a way to access websites and usually not much else.
    - clarry 10y ago
      I think we need a mandate for ISPs to make it clear when the product they're offering is not internet connection.
    - luchs 10y ago
      Is it really? Apart from the missing port-forwarding, DS-Lite seems to be one of the better solutions to the IPv4 shortage to me. There's only a single NAT at the ISP, the local router tunnels IPv4 packages directly to the AFTR. For peer-to-peer applications, both UDP and TCP hole punching work fine. Maybe some ISPs will implement the Port Control Protocol [1] at some point, which would allow port forwarding with the DS-Lite NATs. [1]: https://tools.ietf.org/html/rfc6887 https://tools.ietf.org/html/rfc6887
      - the8472 10y ago
        > For peer-to-peer applications, both UDP and TCP hole punching work fine. Sadly, that's only half correct. Yes, nat traversal usually works to establish connections. But in practice port mappings are not necessarily the same thing as NAT table entries. If your p2p application contacts a lot of endpoints, even from the same source port, this can eventually lead to saturation. At that point you'll get packet drops and ICMP errors. In other words, on some aftr implementations p2p can lead to resource exhaustion, leading to a pretty bad ipv4 experience. > Maybe some ISPs will implement the Port Control Protocol [1] at some point, which would allow port forwarding with the DS-Lite NATs. Some already do. The CPE can forward local mappings to the AFTR.
- ckuehl 10y ago
  ISPs usually use the designated block (100.64.0.0/10) for this to avoid collisions with home networks: https://tools.ietf.org/html/rfc6598#section-7 https://tools.ietf.org/html/rfc6598#section-7 Webpass is an example of a "good" ISP that does this. It's my only qualm with them. Besides that they are outstanding. IPv6 works great.
- klackerz 10y ago
  ISP's in India have started using this method. I am currently using such an ISP.
CountSessine 10y ago
Question - given that they've condemned you to an awful carrier-grade-NAT, do they at least support IPv6? I'm of the opinion that this is probably the future for all residential internet users - ISPs that put everyone on an IPv4 NAT so that grandma can still get her hotmail and yahoo, while hopefully providing unencumbered IPv6 access for everything else that requires a real network connection.
- zigzigzag 10y ago
  That's the world I'm in. Carrier NAT for IPv4, fully working routable IPv6 as designed. Unfortunately this still screws me over because nobody who I might want to connect to my home network has IPv6 yet.
  - subway 10y ago
    You might be surprised how much of your traffic already goes over ipv6. Much of your Google and Facebook traffic, for instance.
    - danieldk 10y ago
      But then a lot of software still only supports IPv4, e.g. Dropbox or Resilio Sync. In the latter case that gives me some serious headaches, it has the tendency to open a lot of connections at once. I think my ISPs DS-Lite uses some quota, because when I have sync open on more than a certain number of devices, IPv4 connections start getting dropped and IPv4 is basically unusable for 5-10 minutes. I am pretty sure it's related to DS-Lite, because it doesn't happen to devices that are connected to a VPN. It would help me a lot if all (mostly proprietary) software vendors would finally start supporting IPv6.
    - zigzigzag 10y ago
      Sure but that's all outbound. What matters to me more is what can connect inbound e.g. p2p apps and most of them do not really do ipv6
- vertex-four 10y ago
TazeTSchnitzel 10y ago
Huh. Does the DWP really need 16 million addresses just to deny people benefit payments?
- virtuallynathan 10y ago
  They started selling them off: http://www.bbc.com/news/technology-32826353 http://www.bbc.com/news/technology-32826353
lloeki 10y ago
> the largest fibre ISPs in the U.K > so were forced into this position. Well it's not like they could have deployed IPv6 (with NAT64) instead (/rant). Most ISPs around here (France) provide IPv6, some of them since like 10 years ago. Not supporting IPv6 today is just ridiculous, and I've jumped ship† regularly during those 10 years, explicitly mentioning IPv6 (lack thereof or unsatisfying support) as the reason when cancelling. I understand that not everyone has this chance (due to choice availability) to pressure their ISPs, but seriously they weren't forced: they dug themselves into this hole. † One of them even dropped a previously perfectly functional IPv6 support for me purely due to a contract update and argued it wasn't possible to bring it back. Seriously.

by nvarsj 10y ago

nmc 10y ago

Seriously? They assign internal addresses (10/8, 172.16/12, 192.168/16) to all customers? Are you able to name the ISP?

knorker 10y ago
Is it rare? I think BT's cheaper broadbands do this, for one.
- tokenizerrr 10y ago
  I certainly have never encountered this, and would be really unhappy if my ISP pulled this stunt.
  - j3097736 10y ago
    Only the early players get the luxury of large IP pools, everyone else has had to resort to carrier-grade NAT. Fortunately some of those can un-NAT you if you ask politely.
- vertex-four 10y ago
  BT does this unless you either have an Unlimited package or opt out through their website.
the8472 10y ago
That's fairly normal these days. The combination of ipv6 + cgnat for ipv4 (carried over the v6) is called DS-Lite[0]. ISPs in asian countries have been doing that for years now european and american ISPs have been ramping it up recently too. [0] https://tools.ietf.org/html/rfc6333 https://tools.ietf.org/html/rfc6333
- userbinator 10y ago
  ISPs in asian countries have been doing that for years And they usually call it "web access" or something similar, never speaking of an "Internet connection". Which is what it is, a way to access websites and usually not much else.
  - clarry 10y ago
    I think we need a mandate for ISPs to make it clear when the product they're offering is not internet connection.
  - luchs 10y ago
    Is it really? Apart from the missing port-forwarding, DS-Lite seems to be one of the better solutions to the IPv4 shortage to me. There's only a single NAT at the ISP, the local router tunnels IPv4 packages directly to the AFTR. For peer-to-peer applications, both UDP and TCP hole punching work fine. Maybe some ISPs will implement the Port Control Protocol [1] at some point, which would allow port forwarding with the DS-Lite NATs. [1]: https://tools.ietf.org/html/rfc6887 https://tools.ietf.org/html/rfc6887
    - the8472 10y ago
      > For peer-to-peer applications, both UDP and TCP hole punching work fine. Sadly, that's only half correct. Yes, nat traversal usually works to establish connections. But in practice port mappings are not necessarily the same thing as NAT table entries. If your p2p application contacts a lot of endpoints, even from the same source port, this can eventually lead to saturation. At that point you'll get packet drops and ICMP errors. In other words, on some aftr implementations p2p can lead to resource exhaustion, leading to a pretty bad ipv4 experience. > Maybe some ISPs will implement the Port Control Protocol [1] at some point, which would allow port forwarding with the DS-Lite NATs. Some already do. The CPE can forward local mappings to the AFTR.
ckuehl 10y ago
ISPs usually use the designated block (100.64.0.0/10) for this to avoid collisions with home networks: https://tools.ietf.org/html/rfc6598#section-7 https://tools.ietf.org/html/rfc6598#section-7 Webpass is an example of a "good" ISP that does this. It's my only qualm with them. Besides that they are outstanding. IPv6 works great.
klackerz 10y ago
ISP's in India have started using this method. I am currently using such an ISP.

CountSessine 10y ago

Question - given that they've condemned you to an awful carrier-grade-NAT, do they at least support IPv6? I'm of the opinion that this is probably the future for all residential internet users - ISPs that put everyone on an IPv4 NAT so that grandma can still get her hotmail and yahoo, while hopefully providing unencumbered IPv6 access for everything else that requires a real network connection.

zigzigzag 10y ago
That's the world I'm in. Carrier NAT for IPv4, fully working routable IPv6 as designed. Unfortunately this still screws me over because nobody who I might want to connect to my home network has IPv6 yet.
- subway 10y ago
  You might be surprised how much of your traffic already goes over ipv6. Much of your Google and Facebook traffic, for instance.
  - danieldk 10y ago
    But then a lot of software still only supports IPv4, e.g. Dropbox or Resilio Sync. In the latter case that gives me some serious headaches, it has the tendency to open a lot of connections at once. I think my ISPs DS-Lite uses some quota, because when I have sync open on more than a certain number of devices, IPv4 connections start getting dropped and IPv4 is basically unusable for 5-10 minutes. I am pretty sure it's related to DS-Lite, because it doesn't happen to devices that are connected to a VPN. It would help me a lot if all (mostly proprietary) software vendors would finally start supporting IPv6.
  - zigzigzag 10y ago
    Sure but that's all outbound. What matters to me more is what can connect inbound e.g. p2p apps and most of them do not really do ipv6
vertex-four 10y ago

TazeTSchnitzel 10y ago

Huh. Does the DWP really need 16 million addresses just to deny people benefit payments?

virtuallynathan 10y ago
They started selling them off: http://www.bbc.com/news/technology-32826353 http://www.bbc.com/news/technology-32826353

lloeki 10y ago

> the largest fibre ISPs in the U.K > so were forced into this position. Well it's not like they could have deployed IPv6 (with NAT64) instead (/rant). Most ISPs around here (France) provide IPv6, some of them since like 10 years ago. Not supporting IPv6 today is just ridiculous, and I've jumped ship† regularly during those 10 years, explicitly mentioning IPv6 (lack thereof or unsatisfying support) as the reason when cancelling. I understand that not everyone has this chance (due to choice availability) to pressure their ISPs, but seriously they weren't forced: they dug themselves into this hole. † One of them even dropped a previously perfectly functional IPv6 support for me purely due to a contract update and argued it wasn't possible to bring it back. Seriously.