The MPLS WG Archive

["venkattr" <venkattr@future.futsoft.com>]

Hi All,

One of the popular solutions proposed to maintain QoS information from the
penultimate hop to the Egress when PHP is implemented, is to insert an
EXPLICIT NULL label with the QoS information encoded into the EXP bits.  It
is here that I have a gap in my understanding.  The determination of QoS
behaviour to be applied to any MPLS packet depends not just on the EXP bits,
but also on the combination of Label + EXP for both Signalled E-LSPs and
L-LSPs.  The only exception is in the case of Pre-Configured E-LSPs when the
EXP bits by themselves are sufficient for the complete determination of the
QoS behaviour.  In that case, is the use of EXPLICIT NULL label with the EXP
bits encoded to convey QoS information between Penultimate Hop and Egress
restricted to Pre-Configured E-LSPs?

Any valuable inputs will be highly appreciated!

Thanks and regards,

-TRV

***************************************************************************
This message is proprietary to Future Software Limited (FSL) 
and is intended solely for the use of the individual to whom it
is addressed. It may contain  privileged or confidential information 
and should not be circulated or used for any purpose other than for 
what it is intended. 

If you have received this message in error, please notify the
originator immediately. If you are not the intended recipient,
you are notified that you are strictly prohibited from using,
copying, altering, or disclosing the contents of this message. 
FSL accepts no responsibility for loss or damage arising from 
the use of the information transmitted by this email including
damage from virus.
***************************************************************************