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draft-ietf-mpls-diff-ext-07.txt

  • From: "Sasha Vainshtein" <sasha@iprad.co.il>
  • Date: Thu, 30 Nov 2000 10:25:06 +0200
  • Importance: Normal

Francis,
	Regarding your example:

	To the best of my understanding AF11, AF12 and AF13 are three DSCPs
belonging to the same PHB (AF1),
	expressing 3 different levels of drop precedence. So you have actually
given an excellnet example of
	an L-LSP (with the scheduling behavior inferred from the label and drop
precedence - from the EXP bits).

	A real example of an E-LSP would be an LSP carrying, say AF-1 and AF-2.
Such a sharing carries with
	it some difficult questions, i.e.how to split the aggregate bandwidth
allocated to an E-LSP between two (or more) PHBs
	with individual bandwidth reservations etc.

______________________________________________
With best regards,
Sasha Vainshtein
mailto: sasha@iprad.co.il
phone: +972-3-7659993 (office)
fax:      +972-3-6487779 (office)


>>-----Original Message-----
>>From: owner-mpls@UU.NET [mailto:owner-mpls@UU.NET]On Behalf Of
>>Francis Arts
>>Sent: Thursday, November 30, 2000 9:39 AM
>>To: mpls@UU.NET
>>Subject: draft-ietf-mpls-diff-ext-07.txt
>>
>>
>>
>>Hello,
>>
>>The draft-ietf-mpls-diff-ext-07.txt defines 2 types of LSPs - E-LSPs and
>>L-LSPs. For the DIFF SERV object defined in this draft, also 2 variants
>>are defined -1 for E-LSPs and 1 for L-LSPs.
>>
>>I have the following question: Why have L-LSPs been defined (instead of
>>defining just 1 type - E-LSPs)? According to my understanding all the
>>capabilities of an L-LSP can be obtained by using an E-LSP with the
>>proper PHB set.
>>
>>Example: Assume that we want to establish an L-LSP for AF1 traffic. We
>>could achieve the same effect (an MPLS tunnel for Af1 traffic) by using
>>an E-LSP with 3 exp <--> PHB mappings:
>>** exp_af11 <--> AF11
>>** exp_af12 <--> AF12
>>** exp_af13 <--> AF13
>>
>>
>>Thanks for your answer.
>>
>>Kind regards,
>>
>>    Francis.
>>
>>