Move the atom:ipaddr construct proposed in PacePersonConstruct out of atom:author to atom:entry.
Members of the community have indicated that the ip address is useful information. However:
HTTP, does not have a 1:1 mapping from user agents to IP addresses. Along with NAT, there is no strong correlation between an IP address and a person; a single IP address may represent many users, and a single user may come from any number of IP addresses, even in the same browsing session.
There are no defined heuristics for this mapping, and any mapping might result in incorrect inferences.
Aside from being a bogus identifier, atom:ippadr is not information actively provided by the author and as such is entirely different in spirit to constructs such as email, name, uri or foaf.
Not every atom:entry can be associated with an ip address, nor is it always required information, hence it should be an optional element.
Make atom:ipaddr and optional child of atom:entry. Proposed spec text:
NN.n "atom:ipaddr" Element The "atom:ipaddr" element's content conveys an IP address associated with the source of the entry. An atom:entry constructs MAY contain an atom:ipaddr element, but MUST NOT contain more than one. Its content MUST be a dotted-decimal IPv4 address or a colon-delimited IPv6 address.