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

["Drake, John E" <John.E.Drake2 at boeing.com>]

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   
> 		
> 
>