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Re: [L2tpext] [PWE3] An error in RFC 4446 "IANA Allocations for PseudowireEdge to Edge Emulation (PWE3)"



Hi John,

One clarification on this:

When client network layer over MPLS-TP LSP directly, the method implies that
client network layer can use this MPLS-TP LSP as a client network link
because the LSP is a bidirectional point to point connection. When client
traffic over a PW, the PW does not guarantee link characteristics.
Therefore, the method only applies to client non-network layer.

Is my understanding correct? 

Regards,
Lucy

 

> -----Original Message-----
> From: pwe3-bounces at ietf.org [mailto:pwe3-bounces at ietf.org] On Behalf Of
> Drake, John E
> Sent: Wednesday, August 19, 2009 8:09 AM
> To: Jiang Yuan-long; neil.2.harrison at bt.com; pwe3 at ietf.org
> Cc: l2tpext at ietf.org
> Subject: Re: [PWE3] An error in RFC 4446 "IANA Allocations for
> PseudowireEdge to Edge Emulation (PWE3)"
> 
> Yuanlong Jiang,
> 
> Please see section 3.4.1 of the MPLS TP Framework I-D:
> 
> http://www.ietf.org/id/draft-ietf-mpls-tp-framework-02.txt
> 
> It describes how client network layer payloads (e.g., IP and MPLS) are
> carried directly, i.e., without a pseudo-wire, over an MPLS TP server
> network.
> 
> Client non-network layer payloads still use pseudo-wires.
> 
> Thanks,
> 
> John
> 
> > -----Original Message-----
> > From: Jiang Yuan-long [mailto:yljiang at huawei.com]
> > Sent: Tuesday, August 18, 2009 7:21 PM
> > To: neil.2.harrison at bt.com; pwe3 at ietf.org
> > Cc: l2tpext at ietf.org
> > Subject: Re: [PWE3] An error in RFC 4446 "IANA Allocations
> > for PseudowireEdge to Edge Emulation (PWE3)"
> >
> > Neil,
> >
> > Thank you for your reply.
> > As Himanshu said in the last email, 0x000B is actually the PW
> > type for IP, rather than L2TP PW type for IP. So I believe it
> > is also feasible for MPLS-TP.
> >
> > I agree with you that there is some difficulty for MPLS label
> > stack to operate in the same manner as client/server layering
> > model, but an adaptation layer such as PW functions now is
> > indispensable.
> >
> >  Best Regards
> > Yuanlong Jiang
> >
> >
> >
> >
> >
> > 	----- Original Message -----
> > 	From: neil.2.harrison at bt.com
> > 	To: yljiang at huawei.com ; pwe3 at ietf.org
> > 	Cc: l2tpext at ietf.org
> > 	Sent: Wednesday, August 19, 2009 4:16 AM
> > 	Subject: RE: [PWE3] An error in RFC 4446 "IANA
> > Allocations for Pseudowire Edge to Edge Emulation (PWE3)"
> >
> > 	Hi Yuanlong Jiang,
> >
> > 	Where you said below:
> > 	"I also wonder whether we should define a PW type for
> > IP payload so that everything on PW is possible"
> >
> > 	This is precisely what a key consequence of MPLS-TP is,
> > ie in the LDP spin of MPLS we had to define PWs (one reason
> > being that LDP requires that IP traffic units can run native
> > in the DP with MPLS traffic units), but given we can't have
> > IP in the MPLS-TP DP and we can't have LDP mp2p merging
> > constructs in MPLS-TP anyway (the latter point is all about
> > resource management determinism) then the original driver for
> > PWs is gone.....just a fact.  So now everything is a PW and
> > nothing is a PW....that is, we just have clients (any) of MPLS-TP.
> >
> > 	We still have a tricky issue with the S bit that is not
> > fully understood IMO yet (S bit => sublayering, as opposed to
> > true client/server layering), which is also related to the
> > important topic of being able to do MPLSoverMPLS as a proper
> > client/server relationship.
> >
> > 	So what you point out below will be the case in MPLS-TP
> > anyway (though I'm not sure everyone is comfortable with the
> > acceptance of this fact yet)
> >
> > 	regards, Neil
> >
> >
> >
> > ________________________________
> >
> > 		From: pwe3-bounces at ietf.org
> > [mailto:pwe3-bounces at ietf.org] On Behalf Of Jiang Yuan-long
> > 		Sent: 18 August 2009 14:01
> > 		To: pwe3 at ietf.org
> > 		Cc: l2tpext at ietf.org
> > 		Subject: [PWE3] An error in RFC 4446 "IANA
> > Allocations for Pseudowire Edge to Edge Emulation (PWE3)"
> >
> >
> > 		Hi, all:
> >
> > 		I came accross an error in RFC 4446 "IANA
> > Allocations for Pseudowire
> > 		Edge to Edge Emulation (PWE3)".
> >
> > 		In Sec 3.2, it says:
> > 		"   0x000B  IP Layer2 Transport
> >              [RFC3032]"
> >
> > 		it should be:
> > 		   0x000B  IP Layer2 Transport
> >       [draft-ietf-l2tpext-pwe3-ip]
> >
> > 		The same problem also exists in web page
> > version http://www.iana.org/assignments/pwe3-parameters
> > <http://www.iana.org/assignments/pwe3-parameters> .
> >
> > 		I wonder how about the status of this expired
> > WG draft, will any more work
> > 		continue on this document or just expired as it is?
> > 		I also wonder whether we should define a PW
> > type for IP payload so that
> > 		everything on PW is possible.
> > 		Any comments?
> >
> > 		   Thanks,
> > 		Yuanlong Jiang
> >
> >
> >
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