Generation of IV for ESP

["Amol Deshmukh" <adeshmukh@pace.stpp.soft.net>]

Hi,

I had a question about the generation of IV for ESP mode.

I have come across following Situations in the various
IPsec Implementations:
1) Implicit IV is used by generating it at the
respective peers by use of SEQ_ID.i.e 
           IV[0-3] = Seq-id;
           IV[4-7] = ~Seq-id; 

Which is the most standard way to use in Implicit IV
case? Or How is the IV generated so that there are 
no interoperatibility issues with different IPsec 
implementations?
    Will the using of sequence ID for generation of IV
solve this issue?

I would be thankful if you could help me with the
above query.

Regards,
-Amol.