[Mobike] When to do Return Routability Checks

[Francis Dupont]

 In your previous mail you wrote:

   this is issue is interesting. in a previous mail i had the impression that
   you argued that only an authorized address can be used for communication
   (non-return-routability-test messages).

=> not exactly because IMHO return-routability-test messages can be
a way to authorize an address, so there can be a case, likely limited
to return-routability-test messages, where a not yet authorized address
may be used for communications.

   if you have an unauthorized address
   you need to perform some authorization check (which might require a return
   routability check) to turn this address into an authorized address which can
   subsequently be used. 
   
=> exactly. Note the authorization is required only for IPsec packets,
for IKE messages connectivity is more important.

   if my observation is correct then you also suggest to have a window larger
   than one in order for the protocol to work.
   
=> IMHO this is not necessary but highly recommended (i.e., SHOULD).
   
Thanks

Francis.Dupont at enst-bretagne.fr