Pseudo-Wire Emulation Edge-to-Edge(PWE3) Zi Kang Liu Jun Internet Draft Huawei Technologies Co., Ltd. Expires: April 2006 October 17, 2005 Link Aggregation Member Interface Status Signal draft-zi-pwe3-link-aggr-member-status-00.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on April 17, 2005. Copyright Notice Copyright (C) The Internet Society (2005). All Rights Reserved. Zi Expires April 17, 2006 [Page 1] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 Abstract Link Aggregation can be used as Attachment Circuit (AC) of the PWE3 service. Link Aggregation is treated as a single interface. But changes in the the member interface may affect use of the aggregated link. This draft suggests a method to signal the status of the member interface of Link Aggregation AC to remote Provider Edge (PE) device. With this status information, the remote PE can decide to discard traffic over bandwidth, avoid congestion at local PE and avoid wasted bandwidth of the Packet Switched Network (PSN). This mechanism is required in PWE3 applications because pseudo-wires provide layer 1/layer 2 services, carrying traffic that may not respond to loss events by executing congestion avoidance Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119 [1]. Table of Contents 1. Introduction................................................2 2. AC Sub-interface Status......................................3 3. Security Considerations......................................5 4. IANA Considerations.........................................5 5. Acknowledgments.............................................6 6. Normative References.........................................6 7. Informative References.......................................6 8. Author's Addresses..........................................7 Intellectual Property Statement.................................7 Disclaimer of Validity.........................................8 Copyright Statement............................................8 Acknowledgment.................................................8 1. Introduction A Link Aggregation interface can be used as an Attachment Circuit (AC) of PWE3 service. A Link Aggregation interface is treated as a single interface. Zi Expires April 17, 2006 [Page 2] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 If, for example, a Link Aggregation includes two operational 100 Mb Ethernet ports, the Link Aggregation interface can pass through 200 Mb traffic. If one of the two ports changes it's status to 'down', the Link Aggregation interface can pass through only 100 Mb traffic. Because the Link Aggregation interface is still up, so the remote Customer Edge (CE) device continues to send out 200 Mb traffic. The 200 Mb traffic may be forwarded to this PE which must discard one half of the traffic. So we need a mechanism to communicate the status of the member interface of the Link Aggregation interface to the remote PE. 2. AC Sub-interface Status The member interface of the Link Aggregation interface can be regarded as a sub-interface of AC. The format of the AC Sub-interface Status TLV is as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1 0| AC Sub-interface Status | 0x0C | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of up Sub-interface | Bandwidth Unit | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Bandwidth | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The values of Bandwidth Unit are specified below: Zi Expires April 17, 2006 [Page 3] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 0x01 bps 0x02 Kbps 0x03 Mbps 0x04 Gbps So the bandwidth of Link Aggregation interface is equal to "Bandwidth" multiplied by "Bandwidth Unit". This TLV is transported to the remote PW peer via the LDP notification message ([PWE3-CRTL] 5.4.2), with the PW Status TLV. The general format of the Notification Message is: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| Notification (0x0001) | Message Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Message ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Status (TLV) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PW Status TLV | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | AC Sub-interface Status TLV | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PWId FEC or Generalized ID FEC | Zi Expires April 17, 2006 [Page 4] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ When one of the member interfaces of the Link Aggregation changes to down or up, a PE that supports this mechanism MUST send the AC Sub- interface Status TLV via a notification message to the remote PE. If the remote PE does not know how to process this TLV, it MUST ignore this TLV because the U bit of this TLV is set [RFC3031]. A remote PE that does know how to process this TLV MAY perform flow control mechanism using the new bandwidth. The number of up Sub- interface may also be used for flow control mechanism. If one of the member interfaces of the Link Aggregation changes to down, but at the same time another member interfaces of the Link Aggregation changes to up, and the bandwidth of Link Aggregation not change, the PE MAY send the AC Sub-interface Status TLV to the remote PE, but is not required to do so if the aggregate bandwidth and number of active member interfaces remain constant. 3. Security Considerations This document does not introduce any new security concerns beyond those specified in [PWE3-CRTL]. 4. IANA Considerations The code of AC Sub-interface Status TLV must be assigned by IANA. (Spencer - is there a value you could suggest? May not need.) Zi Expires April 17, 2006 [Page 5] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 5. Acknowledgments None. 6. Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [2] Crocker, D. and Overell, P.(Editors), "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, Internet Mail Consortium and Demon Internet Ltd., November 1997. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2234] Crocker, D. and Overell, P.(Editors), "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, Internet Mail Consortium and Demon Internet Ltd., November 1997. [PWE3-CRTL] "Pseudowire Setup and Maintenance using the Label Distribution Protocol", Martini L., et al draft-ietf-pwe3- control-protocol-17.txt, ( work in progress ), June 2005. [RFC3031] E. Rosen, et al., RFC 3031, MPLS Architecture, January 2001. 7. Informative References [RFC3985] "PWE3 Architecture" Bryant, et al., RFC3985. Zi Expires April 17, 2006 [Page 6] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 8. Author's Addresses Zi Kang Huawei Technologies Co., Ltd. Floor 10, HuiHong Mansion, No.91 BaiXia Rd. NanJing, P.R. of China Phone: ( 86)25-84565325 Email: zikang@huawei.com Liu Jun Huawei Technologies Co., Ltd. Floor 10, HuiHong Mansion, No.91 BaiXia Rd. NanJing, P.R. of China Phone: ( 86)25-84565327 Email: liujn@huawei.com Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org Zi Expires April 17, 2006 [Page 7] Internet-DraftLink Aggregation Member Interface Status Signal October 2005 Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Statement Copyright (C) The Internet Society (2005). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. 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