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Re: Regarding the pointer field in LSSR options of IP packet.

2000-06-06 08:50:02
  *> Shankar Agarwal <ashankar(_at_)cisco(_dot_)com> wrote:
  *> >
  *> > Can anyone tell me why the minimum value of the pointer in the LSSR 
option
  *> > is 4. It says that it points to the next address with respect to the 
option
  *> > field. Then shouldn't it be 3 (option type + length + pointer) rather 
then 4.
  *> > Similarly for the pointer in the timestamp option it says that
  *> > "The Pointer is the number of octets from the beginning of this
  *> > option to the end of timestamps plus one (i.e., it points to the
  *> > octet beginning the space for next timestamp).  The smallest
  *> > legal value is 5.  The timestamp area is full when the pointer
  *> > is greater than the length."
  *> 
  *> The pointers are 1-based, i.e., a pointer value of 1 would point to the
  *> option type.
  *> 
  *> //cmh
  *> 
  *> 

Yes.  

Some years ago I twigged Jon Postel about this precise issue.  As I
recall, he shrugged his shoulders and said something like "Well, I made
a choice, maybe not the choice I would make today, but... [that's the
way it is, learn to live with it!].

(The part in [] is my interpretation of his shrug).

Bob Braden