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alex / what-happens-when

An attempt to answer the age old interview question "What happens when you type google.com into your browser and press enter?"
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IPv6 Scenario #210

Open daknob opened 8 years ago

daknob commented 8 years ago

We need to also cover the scenario where the address reported by the DNS is IPv6 and the host has IPv6 Capabilities.

Operating Systems like iOS and Mac OS X actually have some algorithms to make sure they give a head start to IPv6 over IPv4.

devopslearn101 commented 2 years ago

@daknob - If you have any idea about the IPV6 flow can you please include it?

lpar commented 2 years ago

IPv6 uses Neighbor Discovery Protocol (NDP) to locate the router, there's no ARP. The DNS server may be located by NDP and RFC 5006, or by DHCPv6. (Or an IPv4 DNS server may be used, since it'll still resolve AAAA records.)

Once the IP address of the web server is resolved, the Happy Eyeballs algorithm is used to determine whether IPv6 or IPv4 gets used to talk to the web server.