What practical problems, aside from address range exhaustion, does it solve? I've read some technical articles about benefits of IPv6, but most of them keep returning to address size problem.
I think a big part of this is address range exhaustion is the root cause of many other problems. For example, IPv6 effectively obsoletes NAT, which removes all kinds of complexity from many protocols (off the top off my head: IPSec, many P2P protocols).
IPv6 also brings saner (IMO) protocol headers, and introduces a variety of other incrementally improved protocols (see ICMPv6, DHCPv6) that have been tweaked with the benefit of years of deployment experience.
IPv6 also brings saner (IMO) protocol headers, and introduces a variety of other incrementally improved protocols (see ICMPv6, DHCPv6) that have been tweaked with the benefit of years of deployment experience.