[aqm] FW: [tsvwg] New Liaison Statement, "Explicit Congestion Notification for Lower Layer Protocols"

["Scheffenegger, Richard" <[e-mail]>]

 
> Title: Explicit Congestion Notification for Lower Layer Protocols
> Submission Date: 2015-07-20
> URL of the IETF Web page: https://datatracker.ietf.org/liaison/1424/
> Please reply by 2015-10-30
> From: Transport Area Working Group (David Black <[e-mail]>)
> To: 3GPP ([e-mail])
> Cc: Gonzalo Camarillo <[e-mail]>,Gorry Fairhurst
> <[e-mail]>,Martin Stiemerling <[e-mail]>,Spencer
> Dawkins <[e-mail]>,John Kaippallimalil
> <[e-mail]>,Bob Briscoe
> <[e-mail]>,Transport Area Working Group Discussion List
> <[e-mail]>
> Response Contact: David Black <[e-mail]>
> Technical Contact: Bob Briscoe <[e-mail]>
> Purpose: For comment
> 
> Body: To: 3GPP SA, 3GPP CT, 3GPP RAN, 3GPP SA4, 3GPP SA2, 3GPP RAN2
> From: IETF TSVWG
> 
> In 2001, the IETF introduced explicit congestion notification (ECN) to the
> Internet Protocol as a proposed standard [RFC3168]. The purpose of ECN was
> to notify congestion without having to drop packets. The IETF originally
> specified ECN for cases where buffers were IP-aware. However, ECN is now
> being used in a number of environments including codec selection and rate
> adaptation, where 3GPP protocols such as PDCP encapsulate IP. As active
> queue management (AQM) and ECN become widely deployed in 3GPP networks and
> interconnected IP networks, it could be incompatible with the standardized
> use of ECN across the end-to-end IP transport [RFC7567].
> 
> The IETF is now considering new uses of ECN for low latency [draft-welzl-
> ecn-benefits] that would be applicable to 5G mobile flows. However, the
> IETF has realized that it has given little if any guidance on how to add
> explicit congestion notification to lower layer protocols or interfaces
> between lower layers and ECN in IP.
> 
> This liaison statement is to inform 3GPP, in particular those groups
> including those involved in 3GPP Release-10 work on the work item ECSRA_LA
> (TR23.860) - SA4, CT4, SA2 and RAN2. Please distribute to all groups that
> have used or plan to use IETF ECN /AQM RFCs in 3GPP specifications.
> 
> The IETF has started work on guidelines for adding ECN to protocols that
> may encapsulate IP and interfacing these protocols with ECN in IP. Then IP
> may act in its role as an interoperability protocol over multiple
> forwarding protocols. This activity is led by the IETF's transport
> services working group (tsvwg).
> 
> Actions:
> The IETF tsvwg kindly asks 3GPP:
> 1) to tell the IETF tsvwg which 3GPP working groups could be affected by
> this work.
> 2) To inform the IETF tsvwg of any specific 3GPP specifications affected
> by this work.
> 3) to forward this liaison statement to these affected working groups, and
> to invite them to review the latest draft of the guidelines, available
> here:
>          < http://tools.ietf.org/html/draft-ietf-tsvwg-ecn-encap-
> guidelines>
> 
> Review comments are particularly welcome on:
>   - comprehensibility for the 3GPP community
>   - usefulness and applicability
>   - technical feasibility
> 
> Review comments may be posted directly to the IETF tsvwg mailing list
> <mailto: [e-mail]>. Postings from non-subscribers may be delayed by
> moderation. Alternatively, subscription is open to all at: <
> https://www.ietf.org/mailman/listinfo/tsvwg>.
> 
> The following IETF specifications or drafts are particularly relevant to
> this activity (the relevance of each of them is explained in the first
> item below):
> * draft-ietf-tsvwg-ecn-encap-guidelines
> * RFC3168 updated by RFC4301, RFC6040 (ECN in respectively: IP/TCP, IPsec
> & IP-in-IP tunnels)
> * RFC6679 (ECN in RTP)
> * RFC5129 updated by RFC5462 (ECN in MPLS)
> * RFC4774 (Specifying alternative semantics for the ECN field)
> * RFC7567 (Recommendations Regarding Active Queue Management
> * draft-welzl-ecn-benefits (Benefits to Applications of Using ECN)
> 
> Yours,
> --David L. Black (TSVWG co-chair)
> Attachments:
> 
> No document has been attached