Re: Link-local connectivity in Web browsers

Here are a few thoughts;

1. As related to the following in the Introduction,

Connectivity is often desirable in such scenarios, and can be accomplished
using link-local addresses. This feature was added in IPv6 [RFC4007] and
retroactively backported to IPv4 [RFC3927].

Section 2.5.6 of RFC 4291, "IP Version 6 Addressing Architecture", defines
the link-local unicast address range, not RFC 4007.

2. In section 3.1, I think you should add that RFC 3986 and the WHATWG URL
Living Standard provide a URI syntax for IPv6 literals, including IPv6
link-local literals, but that syntax does not include a zone identifier.
Such a URI, containing an IPv6 link-local literal without a zone
identifier, is only effective when an operating system supports the
"default" zone, as discussed in section 2.2.

Further, section 3.2 is more about adding a zone identifier to the URI
syntax since IPv6 link-local literals are already in the URI syntax of RFC
3986 and the WHATWG URL Living Standard.

3. I'm not sure where this should go; mDNS ".local" names resolve to all
address types the device has. IPv4, IPv6-LL, IPv6-ULA, and IPv6-GUA
addresses are all frequently available, especially once the device and the
network it is attached to are fully configured. However, sometimes only
link-local addresses are available, especially when configuring the first
devices of a new network, such as a new home broadband router. When
multiple addresses are available, the address used is determined by
RFC6724, "Default Address Selection for Internet Protocol Version 6".

Thanks.
-- 
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David Farmer               Email:farmer@umn.edu
Networking & Telecommunication Services
Office of Information Technology
University of Minnesota
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Minneapolis, MN 55414-3029   Cell: 612-812-9952
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