RE: Reflecting new-MAM/SAM definition in diff-te drafts

["Francois Le Faucheur (flefauch)" <flefauch@cisco.com>]

Hello Jerry,

>> -----Original Message-----
>> From: Dimitry Haskin [mailto:dhaskin@axiowave.com] 
>> Sent: 25 April 2003 22:28
>> To: 'Ash, Gerald R (Jerry), ALABS'; Francois Le Faucheur (flefauch)
>> Cc: te-wg@ops.ietf.org
>> Subject: RE: Reflecting new-MAM/SAM definition in diff-te drafts
>> 
>> 
>> Gerald,
>> 
>> > 3. The 'maximum link bandwidth' parameter is a physical 
>> > constraint and serves to limit the assignable sum of link 
>> > bandwidth across class types.  In the recent discussion, this 
>> > constraint has sometimes been referred to as an 'implicit max 
>> > link BW constraint'.  However there is nothing 'implicit' 
>> > about this constraint/parameter, it is an existing link 
>> > parameter and a physical constraint on assignable link bandwidth.
>> > 4. Given comment #3, we don't need to use the 'max reservable 
>> > link bandwidth' parameter instead of the 'maximum link 
>> > bandwidth' parameter, as you have proposed.
>> 
>> The 'maximum link bandwidth' as defined is the actual link 
>> capacity and not
>> meant to be used as a reservation constraint. The 'max 
>> reservable link
>> bandwidth' was originally defined for this purpose. The 
>> amount of confusion
>> around these definitions puzzles me.
>> 

Do you agree with Dimitry's point that it is the "Max Reservable
Bandwidth" that should be used for constraining reservations (across
Class-Types) - not the "Max Link Bw"- ?  

If yes, would you agree that the following rules would apply for the
"new MAM" definition:
	o for each value of b in the range 0 <= b <= 7: 
		Reserved (CTb) <= BCb, 
	o SUM (Reserved (CTc)) <= Max Reservable Bandwidth, 
		for all "c" in the range 0 <= c <= (MaxCT-1)

Thanks

Francois

>> Dimitry
>> 
>> P.S. Excerpts from draft-katz-yeung-ospf-traffic-09.txt:
>> 
>> 
>>  2.5.6. Maximum Bandwidth
>> 
>>    The Maximum Bandwidth sub-TLV specifies the maximum bandwidth that
>>    can be used on this link in this direction (from the system
>>    originating the LSA to its neighbor), in IEEE floating 
>> point format.
>>    This is the true link capacity.  The units are bytes per second.
>> 
>>    The Maximum Bandwidth sub-TLV is TLV type 6, and is four octets in
>>    length.
>> 
>>  2.5.7. Maximum Reservable Bandwidth
>> 
>>    The Maximum Reservable Bandwidth sub-TLV specifies the maximum
>>    bandwidth that may be reserved on this link in this direction, in
>>    IEEE floating point format.  Note that this may be 
>> greater than the
>>    maximum bandwidth (in which case the link may be oversubscribed).
>>    This SHOULD be user-configurable; the default value should be the
>>    Maximum Bandwidth.  The units are bytes per second.
>> 
>>    The Maximum Reservable Bandwidth sub-TLV is TLV type 7, 
>> and is four
>>    octets in length.
>>