MANET Working Group Sanghyun Ahn Internet Draft Hyun Yu Expires: April 21, 2011 University of Seoul October 18, 2010 A Reliable MANET Routing Mechanism based on the Node Mobility Detection draft-ahn-manet-reliablerouting-00.txt Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. This document may not be modified, and derivative works of it may not be created, except to format it for publication as an RFC or to translate it into languages other than English. 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 25, 2011. 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 publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Ahn, et al. Expires April 25, 2011 [Page 1] Internet-Draft A Reliable MANET Routing Mechanism Oct 2010 Abstract This document describes a reliable MANET routing mechanism based on the node mobility detection. To detect the node mobility, each node maintains the Neighbor Node table and measures the stability of its neighboring environment. Using the route stability information, reliabille routing can be achieved. Table of Contents 1. Requirements notation . . . . . . . . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Node Mobility Detection Mechanism . . . . . . . . . . . . . . 3 5. Reliable MANET Routing . . . . . . . . . . . . . . . . . . . . 4 6. Other Considerations . . . . . . . . . . . . . . . . . . . . . 4 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 5 Ahn, et al. Expires April 25, 2011 [Page 2] Internet-Draft A Reliable MANET Routing Mechanism Oct 2010 1. Requirements notation 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 [RFC2119]. 2. Introduction The MANET routing protocols can be broadly classified into the proactive (table-driven) and the reactive (on-demand) routing protocols [1]. In general, the reactive routing protocols require less overhead than the proactive ones. In the reactive routing approach, a broken link is detected from packet delivery failures and, in this case, each corresponding source node is notified of the link failure so that the source searches for a new path by broadcasting a route request message. Because of the strategy of selecting the minimum hop path, path recomputation may occur frequently in case of high node mobility. In this draft, we describe a reliable MANET routing mechanism based on the node mobility detection. To detect the node mobility, each node maintains the Neighbor Node table and measures the stability of its neighboring environment. Using the route stability information, reliabille routing can be achieved. 3. Terminology Neighbor Node table The table maintained by a node to keep the information on its neighbors. 4. A Mechanism to Detect the Node Mobility In the reactive MANET routing protocols, a node broadcasts HELLO messages periodically to notify its existence to its one-hop neighbors. For the node mobility prediction, we require each node to maintain the Neighbor Node (NN) table. The meaning of each field in the NN table is given in Table 1. Ahn, et al. Expires April 25, 2011 [Page 3] Internet-Draft A Reliable MANET Routing Mechanism Oct 2010 +------------------------+-------------------------------+ | Field | Description | +========================+===============================+ | Neighbor Address | Address of the neighbor node | +------------------------+-------------------------------+ | | Count of the not-received | | Neighbor Entry Counter | HELLO messages from the | | | neighbor | +------------------------+-------------------------------+ | Nighbor Table Timer | Timer | +------------------------+-------------------------------+ The number of the NN table entries varies depending on the network status (i.e., the receiving status of HELLO messages). In the high mobility case, the number of the NN table entries changes more dynamically than the low mobility case. Based on this, each node computes the changes in the number of its NN table entries and predicts the dynamicity of its neighboring environment. Each node computes the average number of its NN table entries, E_n, and the changes of its NN table entries, V_n, at the n-th time period. E_n = W_1 * e_n + (1 - W_1) * e_(n-1) (1) V_n = W_2 * (e_n - E_n) ^ 2 + (1 - W_2) * V_(n-1) (2) In Eq. (1), e_n is the number of the NN table entries at the n-th time period and W_1 is the weight for E_n. In Eq. (2), W_2 is the weight for V_n. 5. A Reliable MANET Routing Mechanism A new field, PathVar, is newly defined in the RREQ message, which is used to include the largest V_n of the path traversed by the RREQ message. Thus, PathVar indicates the stability (i.e., the reliability) of the path. On receiving a RREQ message, the node compares the PathVar in the RREQ message with that in its routing table. If the PathVar in the RREQ message is smaller, the node updates its routing according to the RREQ message and forwards the RREQ message. 6. Other Considerations TBD. Ahn, et al. Expires April 25, 2011 [Page 4] Internet-Draft A Reliable MANET Routing Mechanism Oct 2010 References [1] C. Perkins, Ad Hoc Networking, Addison Wesley, 2001. [2] C. Perkins and E. Royer, "Ad Hoc On Demand Distance Vector (AODV) Routing", RFC 3561, July 2003. [3] T. Clausen and P. Jacquet, "Optimized Link State Routing Protocol (OLSR)", RFC 3626, Oct. 2003. [4] David B.Johnson, David A.Maltz and Yih-Chun Hu, "The Dynamic Source Routing Protocol for Mobile Ad Hoc Networks (DSR)", RFC 4728, February 2007. Authors' Addresses Sanghyun Ahn University of Seoul 90, Cheonnong-dong, Tongdaemun-gu Seoul 130-743 Korea Email: ahn@uos.ac.kr Hyun Yu University of Seoul 90, Cheonnong-dong, Tongdaemun-gu Seoul 130-743 Korea Email: finalyu@gmail.com Ahn, et al. Expires April 25, 2011 [Page 5]