[lisp] Some basic questions ...

[Marc Binderberger <[e-mail]>]

Hello LISP experts,

have two questions, mainly to understand the context a bit better.

Q1: map-notify message.

maybe it's the name but I always expected this message is for the Map 
Server to inform ETRs. Kind of a "push" method. But reading RFCs 6830 
and 6833 again it seems that the Map-Notify is simply an ACK for a 
received and processed Map-Register message. Take the Map-Register 
message, set the type to Map-Notify and send back.

Now, the use as ACK is not a contradiction to the broader use as a push 
message. So my question to the LISP experts and inventors is: is 
Map-Notify restricted to be just an ACK? (having an extra type for it 
seems generous)



Q2: Locator-Status-Bits (LSBs).

RFC 6830 says in section 6.3:

   When an ETR decapsulates a packet, it will check for any change in
   the 'Locator-Status-Bits' field.

I interpret this that if an ITR sets the Locator-Status-Bits then it 
would do so permanently. In other words the LSBs are not set used in an 
"alert style" (means: only set when an RLOC change happened) ?

Wondering what requirements this imposes on the data plane. It may not 
be possible for the "hardware" (NP, ASIC, FPGA) to check the incoming 
LSBs. So if LSBs are sent permanently this would likely require to punt 
every Nth packet to the control plane?



Q3: the lexicographic order of RLOCs.

Maybe stupid question but the lexicographic order is computed over what 
byte sequence exactly?  Loc-AFI + Locator? (both in network order, 
Loc-AFI first)



Thanks & Regards,
Marc