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>The ISP should give every SOHO/residential customer a /60. The ISP should give every residence 295 quintillion IPv6 addresses? I know there is an abundance of
by m348e912 2y ago
>The ISP should give every SOHO/residential customer a /60.
The ISP should give every residence 295 quintillion IPv6 addresses? I know there is an abundance of ipv6 addresses but that seems like a lot of waste.
Even assigning a /96 would provide 4.3 billion ipv6 addresses (which is the same number as all ipv4 addresses in existence)
And since available ipv6 space is basically 4.3 Billion^2, assigning an ipv6 /96 would be like assigning a /32 in ipv4 terms of total ipv6 space utilization.
- mbirth 2y ago/64 is needed for SLAAC to work and is basically the default. Anything larger (usually /56, sometimes even /48) gives the customers a chance to segment their LAN.
- unethical_ban 2y agoLike other person said, /64 is the minimum subnet size. And submitting in ipv6 is best done 4 bits at a time. A /60 is overkill for residents, but because it gives 16 subnets, not because it gives excessive addresses.
- megous 2y agoThere's no minimum subnet size.
- immibis 2y ago/64 acts as a soft limit due to the prevalence of SLAAC. Which is good in a way, since it means ISPs have to give out at least /64, which means you're always able to subnet (although you can't use SLAAC and must use static addresses or DHCP) unlike IPv4 where you have to pay for extra addresses.
- GoblinSlayer 2y agoThe purpose of SLAAC intends to have many customers in one /64 network though.
- immibis 2y agoNo, just many devices. You can DoS your whole subnet by pretending to be a billion devices. In IPv4 you can do it by occupying all the IP addresses. Therefore putting several customers on one network is a bad idea, just like in IPv4.
- icedchai 2y agoThe purpose of SLAAC is to make it "easy" for a client to get onto the network without something like a DHCP server tracking addresses. If you set it up, it generally just works.
- GoblinSlayer 2y agoPreviously it worked by putting the MAC address in the last 64 bits.
- icedchai 2y agoYes, that was before privacy extensions. It hasn't been like that (in most implementations) for a very long time.
- GoblinSlayer 2y agoAnd you get no privacy if /64 prefix is a stable identifier of one customer.
- icedchai 2y agoThis doesn't seem like an IPv6-specific issue. For most broadband customers, your external IPv4 address is also generally stable. Mine hasn't changed in years.
- megous 2y agoYes, you can't use SLAAC feature, but there's no subnetting limit in IPv6. Any subnet size works. Writing to you from /72.
- unethical_ban 2y agoYou're technically correct, but ISPs best practice is to hand out a /64.
- Dylan16807 2y agoThat's not how you're supposed to use IPv6. It would just be 64 bits if that was the case. Instead, 99% of the time, it's a 64 bit subnet ID and a 64 bit device ID.