5 ms·

I’m in the ARIN region. Two things: 1. My home has Verizon fiber. No native IPv6. I have a tunnel for this, but such solutions aren’t going to work for the mas

I’m in the ARIN region. Two things: 1. My home has Verizon fiber. No native IPv6. I have a tunnel for this, but such solutions aren’t going to work for the masses. The other in-region residential provider, Comcast, has great native IPv6 service, but had layer 2 performance issues versus price. 2. At $dayjob I just ordered a circuit from Level3/Centurylink for a branch site. No IP justification form was required if I needed only IPv4 /30. But for dual IPv4 /30 + IPv6 /126, I was required to provide written justification. Shouldn’t this be the other way around? Unencumbered IPv6 for all, with paperwork for IPv4? EDIT: these are not site allocations, just point-to-point link addresses, hence the /126. Still, I’m being asked to justify IPv6 but not IPv4.

kstrauser 7y ago
A /126, seriously? Comcast Business gave us a /56, unprompted, as part of our account setup.
- RKearney 7y ago
  This sounds like a simple P2P link to do BGP over. I highly doubt CL is using /126’s as standard allocation sizes.
  - kstrauser 7y ago
    That makes a lot more sense! Good call.
- cyberpunk 7y ago
  My home connection has a /56 (o2/telephonica de) ....
  - rndgermandude 7y ago
    Yeah, I too got a /56, same country, different ISP. It just showed up one day, which confused me at first.
    - winkeltripel 7y ago
      > It just showed up one day, which confused me at first. I've heard this pretty often. One day it gets rolled out without any notice, and surprise, you're on V6. Plays havoc.
q3k 7y ago
> IPv6 /126 Uh, unless you're running BGP over this or getting a larger subnet statically routed to you, get a larger prefix. A /48 or /56 is the current recommendation [1] for business end site allocations. [1] - https://tools.ietf.org/html/rfc6177 https://tools.ietf.org/html/rfc6177
- souterrain 7y ago
  Of course, this is just a “point-to-point Ethernet” not an allocation. That said, I think the original intent was that such “point-to-point Ethernets” should have been issued /64, but seems /126 is common practice.
  - throw0101a 7y ago
    Actually many ISPs do not even give out a fully routable /126, but simply use an LL fe80:: address for the CPE: * https://www.ripe.net/publications/docs/ripe-690#4-1-2--unnumbered https://www.ripe.net/publications/docs/ripe-690#4-1-2--unnum...
  - colechristensen 7y ago
    Comcast gives out /64s at least. I got my router to successfully ask for 2 on different interfaces.
    - drbawb 7y ago
      Same story on Spectrum. On their residential plans they will give out a /64 by default. However w/ DHCPv6-PD I was able to successfully request a /56. What I found mildly interesting was they wouldn't allocate a /60. (My guess was: whatever silicon they've got pushing IPv6 packets around probably likes segmenting the routing table on a clean byte boundary.)
- windexh8er 7y ago
  Providers don't give out publicly routable /126. Generally most providers aren't going to give out anything longer than a /64 partially because they don't need to and partially because routing tables [0]. They want to route to you via a prefix that's pre-allocated to carve up for the region you're in. [0] https://www.ripe.net/publications/docs/ripe-690 https://www.ripe.net/publications/docs/ripe-690
tzs 7y ago
Maybe their thinking is that if you are just requesting IPv4 you probably aren't set up to support IPv6, but if you ask for IPv4 + IPv6 then they want to know why you can't just use IPv6 for everything and so ask for justification for using IPv4?
- zAy0LfpBZLC8mAC 7y ago
  Which would be about the most braindead reasoning ever?!
- nashashmi 7y ago
  Can you really use ipv6 for everything? I thought only ipv4 could do that?
  - bluGill 7y ago
    If you are a user sure. There are ways to bridge IPv6 to IPv4 (A router someplace translates for you, I suppose NAT but I'm not an expert on how this works), while going the reverse is harder because there is no way to bridge IPv4 to IPv6. There are a lot of people running IPv6 only who don't even know it. (most cell phones for example) Only server administrators need to care, and there they have a problem. If you run real IPv4 only: then IPv6 only users can talk to your server no problem and won't even realize anything is happening. If you run IPv6 only there are a lot of IPv4 only users who cannot connect to you. Thus if you run a server it is critical to have a real IPv4 address. Did you notice the "real" qualifier to IPv4 in that last paragraph? many (most?) IPv4 only users are behind a NAT system such that they cannot run a server anyway. If you are running a IPv4 Server you need an address of the type that RIPE just ran out of. If you are a user you can use a fake IPv4 address and keep on working. If you are a server administrator you should ensure that all your servers have IPv6 addresses. You should then collect statistics on use. There may be a date in the future where you can suggest to your management that you can cut off [small number]% of your users by going IPv6 only and selling your existing IPv4 address to the highest bidder for $$$. That is a business decision, but once it starts happening it will make headlines, but I wouldn't want to be first. (if you wait too long enough others will have gone IPv6 only that there isn't a real customer cost to being IPv6 only and then the market for IPv4 will disappear - and interesting value maximization problem if you want to play that game)
dheera 7y ago
Unfortunately we're just not at a stage yet where anyone can easily associate a static IPv6 to an EC2 instance and expect it to "just work". My phone isn't always happy visiting IPv6 addresses. Many coffee shops and university wifi I regularly use don't support IPv6. My home router doesn't seem to route IPv6 correctly (or maybe it's Comcast's problem; I don't know; I gave up because everything I use can work over IPv4 as well :-/). My work internet connection doesn't route IPv6, either. I'm all for IPv6 but it's not widespread enough to ditch the need for static IPv4 addresses.
- yuvadam 7y ago
  Transitioning to native IPv6 requires running dual stack for quite some time, we'll never get there if we don't start
  - tialaramex 7y ago
    Not necessarily. A network can go entirely IPv6 internally and just have adaptors at the edge to translate parts of the Internet that aren't IPv6 yet. Doing this means all IPv4 network addressing headaches vanish internally. Oh there are going to be 260 remote offices instead of 100 like you said at the kick off meeting? No problem, my subnets are easily big enough either way. And with this approach your budget for the edge reduces over time as more of the network supports IPv6, whereas with a NAT gateway your budget increases as throughput rises. You do need to be really firm during purchases, if the "IPv6 support" in that shiny new product is actually more of a wishlist item than an actual feature, you're getting a full refund, no second chances. That goes for desk phone (if your outfit still has those), printer/ copiers, IoT devices, and everything.
  - koolba 7y ago
    I’ve heard some variant of that for over two decades and still here we are.
    - kitteh 7y ago
      In the early 2000s the issue was the routing hardware did ipv6 shitty. That took a few years to get to a better spot (and a few years more to get it almost at IPv4 parity feature wise). Then it took a few more years for transit providers to roll it out...then the broadband networks. Now we're in a time when v6 support is mixed across cloud companies and there are large swaths of geographical areas that are lagging (sup Central and South America + china). Were closer...
zarangu 7y ago
Here's another fun one: how many usable IPs do you get out of the 4 consumed by that /30? Not sure about L3 specifically but it seems a lot of ISPs haven't yet figured out that it's not necessary to waste half the IPs in every /30 allocation with gateway and broadcast IP.
- ndespres 7y ago
  Spectrum/Charter and Verizon have finally started allocating a single IP out of a /24 instead of giving me a whole /30 when all I need is one routable address. Too little too late though.
  - hhw 7y ago
    I think you're missing the parent's point, that you can use a /31 without separate network (not gateway) and broadcast addresses. Putting multiple customers on the same /24 introduces all kinds of issues. Either you leave it open leaving IP's vulnerable to hijacking, or you have to create static ARP and/or MAC entries, and deal with all the hassle of managing that. Presumably, you're describing consumer service where they don't really have to care about your security unlike a business/enterprise level service.

kstrauser 7y ago

A /126, seriously? Comcast Business gave us a /56, unprompted, as part of our account setup.

RKearney 7y ago
This sounds like a simple P2P link to do BGP over. I highly doubt CL is using /126’s as standard allocation sizes.
- kstrauser 7y ago
  That makes a lot more sense! Good call.
cyberpunk 7y ago
My home connection has a /56 (o2/telephonica de) ....
- rndgermandude 7y ago
  Yeah, I too got a /56, same country, different ISP. It just showed up one day, which confused me at first.
  - winkeltripel 7y ago
    > It just showed up one day, which confused me at first. I've heard this pretty often. One day it gets rolled out without any notice, and surprise, you're on V6. Plays havoc.

q3k 7y ago

> IPv6 /126 Uh, unless you're running BGP over this or getting a larger subnet statically routed to you, get a larger prefix. A /48 or /56 is the current recommendation [1] for business end site allocations. [1] - https://tools.ietf.org/html/rfc6177 https://tools.ietf.org/html/rfc6177

souterrain 7y ago
Of course, this is just a “point-to-point Ethernet” not an allocation. That said, I think the original intent was that such “point-to-point Ethernets” should have been issued /64, but seems /126 is common practice.
- throw0101a 7y ago
  Actually many ISPs do not even give out a fully routable /126, but simply use an LL fe80:: address for the CPE: * https://www.ripe.net/publications/docs/ripe-690#4-1-2--unnumbered https://www.ripe.net/publications/docs/ripe-690#4-1-2--unnum...
- colechristensen 7y ago
  Comcast gives out /64s at least. I got my router to successfully ask for 2 on different interfaces.
  - drbawb 7y ago
    Same story on Spectrum. On their residential plans they will give out a /64 by default. However w/ DHCPv6-PD I was able to successfully request a /56. What I found mildly interesting was they wouldn't allocate a /60. (My guess was: whatever silicon they've got pushing IPv6 packets around probably likes segmenting the routing table on a clean byte boundary.)
windexh8er 7y ago
Providers don't give out publicly routable /126. Generally most providers aren't going to give out anything longer than a /64 partially because they don't need to and partially because routing tables [0]. They want to route to you via a prefix that's pre-allocated to carve up for the region you're in. [0] https://www.ripe.net/publications/docs/ripe-690 https://www.ripe.net/publications/docs/ripe-690

tzs 7y ago

Maybe their thinking is that if you are just requesting IPv4 you probably aren't set up to support IPv6, but if you ask for IPv4 + IPv6 then they want to know why you can't just use IPv6 for everything and so ask for justification for using IPv4?

zAy0LfpBZLC8mAC 7y ago
Which would be about the most braindead reasoning ever?!
nashashmi 7y ago
Can you really use ipv6 for everything? I thought only ipv4 could do that?
- bluGill 7y ago
  If you are a user sure. There are ways to bridge IPv6 to IPv4 (A router someplace translates for you, I suppose NAT but I'm not an expert on how this works), while going the reverse is harder because there is no way to bridge IPv4 to IPv6. There are a lot of people running IPv6 only who don't even know it. (most cell phones for example) Only server administrators need to care, and there they have a problem. If you run real IPv4 only: then IPv6 only users can talk to your server no problem and won't even realize anything is happening. If you run IPv6 only there are a lot of IPv4 only users who cannot connect to you. Thus if you run a server it is critical to have a real IPv4 address. Did you notice the "real" qualifier to IPv4 in that last paragraph? many (most?) IPv4 only users are behind a NAT system such that they cannot run a server anyway. If you are running a IPv4 Server you need an address of the type that RIPE just ran out of. If you are a user you can use a fake IPv4 address and keep on working. If you are a server administrator you should ensure that all your servers have IPv6 addresses. You should then collect statistics on use. There may be a date in the future where you can suggest to your management that you can cut off [small number]% of your users by going IPv6 only and selling your existing IPv4 address to the highest bidder for $$$. That is a business decision, but once it starts happening it will make headlines, but I wouldn't want to be first. (if you wait too long enough others will have gone IPv6 only that there isn't a real customer cost to being IPv6 only and then the market for IPv4 will disappear - and interesting value maximization problem if you want to play that game)

dheera 7y ago

Unfortunately we're just not at a stage yet where anyone can easily associate a static IPv6 to an EC2 instance and expect it to "just work". My phone isn't always happy visiting IPv6 addresses. Many coffee shops and university wifi I regularly use don't support IPv6. My home router doesn't seem to route IPv6 correctly (or maybe it's Comcast's problem; I don't know; I gave up because everything I use can work over IPv4 as well :-/). My work internet connection doesn't route IPv6, either. I'm all for IPv6 but it's not widespread enough to ditch the need for static IPv4 addresses.

yuvadam 7y ago
Transitioning to native IPv6 requires running dual stack for quite some time, we'll never get there if we don't start
- tialaramex 7y ago
  Not necessarily. A network can go entirely IPv6 internally and just have adaptors at the edge to translate parts of the Internet that aren't IPv6 yet. Doing this means all IPv4 network addressing headaches vanish internally. Oh there are going to be 260 remote offices instead of 100 like you said at the kick off meeting? No problem, my subnets are easily big enough either way. And with this approach your budget for the edge reduces over time as more of the network supports IPv6, whereas with a NAT gateway your budget increases as throughput rises. You do need to be really firm during purchases, if the "IPv6 support" in that shiny new product is actually more of a wishlist item than an actual feature, you're getting a full refund, no second chances. That goes for desk phone (if your outfit still has those), printer/ copiers, IoT devices, and everything.
- koolba 7y ago
  I’ve heard some variant of that for over two decades and still here we are.
  - kitteh 7y ago
    In the early 2000s the issue was the routing hardware did ipv6 shitty. That took a few years to get to a better spot (and a few years more to get it almost at IPv4 parity feature wise). Then it took a few more years for transit providers to roll it out...then the broadband networks. Now we're in a time when v6 support is mixed across cloud companies and there are large swaths of geographical areas that are lagging (sup Central and South America + china). Were closer...

zarangu 7y ago

Here's another fun one: how many usable IPs do you get out of the 4 consumed by that /30? Not sure about L3 specifically but it seems a lot of ISPs haven't yet figured out that it's not necessary to waste half the IPs in every /30 allocation with gateway and broadcast IP.

ndespres 7y ago
Spectrum/Charter and Verizon have finally started allocating a single IP out of a /24 instead of giving me a whole /30 when all I need is one routable address. Too little too late though.
- hhw 7y ago
  I think you're missing the parent's point, that you can use a /31 without separate network (not gateway) and broadcast addresses. Putting multiple customers on the same /24 introduces all kinds of issues. Either you leave it open leaving IP's vulnerable to hijacking, or you have to create static ARP and/or MAC entries, and deal with all the hassle of managing that. Presumably, you're describing consumer service where they don't really have to care about your security unlike a business/enterprise level service.