[Diffserv] [OFFLIST] MPLS+Diffserv(mapping DSCP to EXP)

nerdboy <nerdboy@rediffmail.com> Tue, 04 February 2003 06:25 UTC

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From: nerdboy <nerdboy@rediffmail.com>
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Subject: [Diffserv] [OFFLIST] MPLS+Diffserv(mapping DSCP to EXP)
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i know this is offtopic but i didnt know where else to ask.

i understand that the EXP bits in MPLS are used to provide DSCP 
functionality(Diffserv) for EXp inferred LSP's in MPLS.

1. i want to know how the DSCP bits are mapped to the EXP bits ?

2. Further, since the DSCP  ( pow(2,8) = 256 combinations ) is 8 bits and 
provides 22 different PHB's(or roughly 7 different classes),
     and the EXP is just 3 bits and therefore can provide only upto 8 
different classes, wouldnt there be loss of info while mapping DSCP->EXP ?

any help would be greatly appreciated.

Warm Regards
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