A list of important HIPv2 changes for implementors

Hello,

currently there are at least two efforts to create HIPv2 that I know of.
I believe compiling a list of implementation changes that need to be done
in order to transform a HIPv1 into a HIPv2 implementation might be useful.
I'll try to make this list as complete as I can. Please feel free to
respond to this e-mail to add more changes. I also tried to keep this
short and concise. Please respond if you don't understand what I mean.

The items on this list are often related. I tried not to bundle related
things to avoid oversimplification - as a result some things pop up twice
in the list.

This list is not intended as complete guide but it should serve to make a
implementor's life a bit easier by highlighting important changes. It is
intended to be something like a checklist but it cannot be used as sole
basis for upgrading an HIPv1 implementation. This list assumes that the
reader is familiar with RFC5201 and the -bis document.

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 1) HIP Version Number:
    dual implementations should use the version numbers to distinguish
    HIPv1 and HIPv2 packets.

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 2) Signature and Hash Algorithms:
    HIPv2 supports more options than HIPv1 support for these
    algorithms is required. Also the default algorithms are