Working Group Z. Cao Internet-Draft D. Liu Intended status: Informational H. Deng Expires: August 5, 2010 China Mobile February 2010 Light-weight TCP/IP Stack for Lossy and Low-power Networks draft-cao-lightweight-ip-00 Abstract This document describes the requirements for a new lightweight TCP/IP stack for the Low-power and Lossy Networks, such as wireless sensor networks, 802.15.4 enabled networks, and Machine-to-Machine type communication (M2M). Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and 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 August 5, 2010. Copyright Notice Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of Cao, et al. Expires August 5, 2010 [Page 1] Internet-Draft LwIP February 2010 publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Characteristics of LLN . . . . . . . . . . . . . . . . . . . . 4 2.1. Latency . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Low Power . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3. Data Rates . . . . . . . . . . . . . . . . . . . . . . . . 4 2.4. Small Packets . . . . . . . . . . . . . . . . . . . . . . . 4 2.5. Asymmetry Link . . . . . . . . . . . . . . . . . . . . . . 4 2.6. Packet Loss . . . . . . . . . . . . . . . . . . . . . . . . 4 2.7. Burst Congestion . . . . . . . . . . . . . . . . . . . . . 4 3. Requirements for Lightweight TCP/IP Stack . . . . . . . . . . . 5 3.1. Light-weight IP stack for LLN . . . . . . . . . . . . . . . 5 3.2. Smart Congestion Control Protocol . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7 6. Normative References . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9 Cao, et al. Expires August 5, 2010 [Page 2] Internet-Draft LwIP February 2010 1. Introduction This document describes the requirements for a new lightweight TCP/IP stack for the Low-power and Lossy Networks, such as wireless sensor networks, 802.15.4 enabled networks, and Machine-to-Machine type communication (M2M). Cao, et al. Expires August 5, 2010 [Page 3] Internet-Draft LwIP February 2010 2. Characteristics of LLN 2.1. Latency The latency of M2M link is high mostly due to the low data rate. 2.2. Low Power Typically, some or all devices are battery operated. 2.3. Data Rates The data rate for 802.15.4-2006 is 20-250 Kbps. The data rate required for 802.15.4g is 40-1000 Kbps. 2.4. Small Packets Applications within LoWPANs are expected to originate small packets. Adding all layers for IP connectivity should still allow transmission in one frame without incurring excessive fragmentation and reassembly. Furthermore, protocols must be designed or chosen so that the individual "control/protocol packets" fit within a single 802.15.4 frame. Along these lines, IPv6's requirement of sub-IP reassembly may pose challenges for low-end LoWPAN devices that do not have enough RAM or storage for a 1280-octet packet. 2.5. Asymmetry Link Due to the power constrain, some node may only be able to receive packets but not able to send packets. This results into asymmetry links in the network. 2.6. Packet Loss Packet loss is high due to the unstable of LLN. 2.7. Burst Congestion Nodes in the same region may send out packets simultaneously if some events happen there. This may cause network congestion. But for most time, the network is immune to congestion due to its small packet size. In one word, the congestion happens in a burst pattern. This feature needs to be investigated for the design of the new transport protocol. Cao, et al. Expires August 5, 2010 [Page 4] Internet-Draft LwIP February 2010 3. Requirements for Lightweight TCP/IP Stack 3.1. Light-weight IP stack for LLN TBD. 3.2. Smart Congestion Control Protocol TBD. Cao, et al. Expires August 5, 2010 [Page 5] Internet-Draft LwIP February 2010 4. Security Considerations TBD. Cao, et al. Expires August 5, 2010 [Page 6] Internet-Draft LwIP February 2010 5. IANA Considerations This document does not require any IANA actions. Cao, et al. Expires August 5, 2010 [Page 7] Internet-Draft LwIP February 2010 6. Normative References [DNS64] Bagnulo, M., "DNS64: DNS extensions for Network Address Translation from IPv6 Clients to IPv4 Servers", December 2009, . [DNS64-Config] Wing, D., "DNS64 Resolvers and Dual-Stack Hosts", Oct 2009, . Cao, et al. Expires August 5, 2010 [Page 8] Internet-Draft LwIP February 2010 Authors' Addresses Zhen Cao China Mobile Unit2, 28 Xuanwumenxi Ave,Xuanwu District Beijing 100053 China Email: zehn.cao@gmail.com Dapeng Liu China Mobile Unit2, 28 Xuanwumenxi Ave,Xuanwu District Beijing 100053 China Email: liudapeng@chinamobile.com Hui Deng China Mobile Unit2, 28 Xuanwumenxi Ave,Xuanwu District Beijing 100053 China Email: denghui@chinamobile.com Cao, et al. Expires August 5, 2010 [Page 9]