Carriage providers on the other hand see World IPv6 day as almost like a huge denial of service attack against their networks. Among other things they’re worried that they will be swamped by expensive tech support calls as customers can’t get to their favorite web sites. Some carriage providers are planning to block IPv6 traffic on World IPv6 day to protect their networks.
Meanwhile, the fact that many ISPs pay extra for equipment to put millions of internet users behind NAT and TAKE AWAY IPv4 addresses, even though they could get IPv4 addresses practically for free, makes it look to me unlikely that a lot of ISPs will pay extra to do the opposite and give out IPv6 addresses any time soon."
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