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Do ISPs really give out /128s? That's, erm, that's monstruous! Mine gives a /60 but their router doesn't have any way to use it, which is a bit shit. Still, 10 gigs symmetric...



Rogers in Canada gives out a /64 by default, and a /56 if you send a hint.

Bell, on the other hand, gives a big fat /nothing and doesn't support IPv6. I don't understand how they can roll out 1.5Gbit FTTH but refuse to support IPv6. Their mobile network uses it, of course, so it's truly perplexing.


> Bell, on the other hand, gives a big fat /nothing and doesn't support IPv6.

Meanwhile Teksavvy, who piggybacks over Bell's copper and is also using PPPoE for DSL 'logins', has been giving out IPv6 for a couple of years now.


Spectrum here in Austin TX assigns me a /128


If you request a prefix delegation using DHCPv6 you will get up to a /56 which you can subnet.

8 bits of subnetting means you can create up to 256 different subnets.


Your router may be doing something wrong because DHCPv6-PD worked fine for me on Spectrum Austin.


My two data points:

- Spectrum gave me /64.

- Comcast gives me /128.


Spectrum and Comcast both will happily hand out prefix delegations that are larger than the /64.

Comcast for example right now is giving me a /128 for my router, and a /60 which I have used to set up multiple VLAN's.

Spectrum will give you a /56 in a prefix delegation, and a /128 for the router.


Comcast uses /64 for the WAN network and will give you up to a /60 routed prefix for LAN-side networks.


Which means the /64 is not usable if you want to do subnetting and use SLAAC and the /128 is not useable at all if you have more than one machine.

No such issues with v4.

That was my point about subnetting.


I had the /64 via DHCPv6-PD/SLAAC.

The /128 is given to any clients that connect as there is no NAT and the ISP isn't worried if I use a thousand addresses.


A /128 is a single address and given the state of v6 NAT that means it can’t be shared with other machines in your network which means only your router will be able to access the v6 internet without the router being a proxy and you using it


No it means my router is not routing IPv6 traffic. It doesn't need to though. My router and all of my computers each have /128 addresses. No issues. 19/20 on ipv6-test.com.


I got a /48, and I think it will take me a while to put all those addresses in use. I'm using 9-10 now, so while I've certainly started down the path, the end is not in sight just yet.


You need a /48 (or /56) if you want to do your own subnetting and keep using SLAAC (which is the default way for assigning v6 addresses and detecting address conflicts).

A /64 is not enough for that. You can still create your own subnets, but you will be on your own with address assignment


Name and shame the ISP that won't let you do a prefix delegation request to get a larger prefix assigned...


BellAliant in eastern Canada, the only provider of residential layer 1 fiber in my area, still isn't even assigning a /128 or /64, let alone proper delegation.


That's an ISP that apparently still doesn't offer IPv6 at all... not an ISP that has a misconfigured IPv6 network.


Not offering IPv6 is intentional misconfiguration in this day and age, and deserves shame.




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