Mobile Ad hoc Networks Working I. Chakeres Group Boeing Internet-Draft C. Perkins Expires: April 5, 2007 Nokia October 2, 2006 Dynamic MANET On-demand (DYMO) Routing draft-ietf-manet-dymo-06 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 5, 2007. Copyright Notice Copyright (C) The Internet Society (2006). Abstract The Dynamic MANET On-demand (DYMO) routing protocol is intended for use by mobile nodes in wireless, multihop networks. It offers adaptation to changing network topology and determines unicast routes between nodes within the network on-demand. Chakeres & Perkins Expires April 5, 2007 [Page 1] Internet-Draft DYMO October 2006 Table of Contents 1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Data Structures . . . . . . . . . . . . . . . . . . . . . . . 6 4.1. Route Table Entry . . . . . . . . . . . . . . . . . . . . 6 4.2. DYMO Messages . . . . . . . . . . . . . . . . . . . . . . 7 4.2.1. Generalized MANET Packet and Message Structure . . . . 7 4.2.2. Routing Messages (RM) - RREQ & RREP . . . . . . . . . 8 4.2.3. Route Error (RERR) . . . . . . . . . . . . . . . . . . 10 5. Detailed Operation . . . . . . . . . . . . . . . . . . . . . . 12 5.1. DYMO Sequence Numbers . . . . . . . . . . . . . . . . . . 12 5.1.1. Maintaining A Node's Own Sequence Number . . . . . . . 12 5.1.2. Incrementing OwnSeqNum . . . . . . . . . . . . . . . . 13 5.1.3. OwnSeqNum Rollover . . . . . . . . . . . . . . . . . . 13 5.1.4. Actions After OwnSeqNum Loss . . . . . . . . . . . . . 13 5.2. DYMO Routing Table Operations . . . . . . . . . . . . . . 13 5.2.1. Judging Routing Information's Usefulness . . . . . . . 13 5.2.2. Creating or Updating a Route Table Entry with New Routing Information . . . . . . . . . . . . . . . . . 15 5.2.3. Route Table Entry Timeouts . . . . . . . . . . . . . . 15 5.3. Routing Messages . . . . . . . . . . . . . . . . . . . . . 17 5.3.1. RREQ Creation . . . . . . . . . . . . . . . . . . . . 17 5.3.2. RREP Creation . . . . . . . . . . . . . . . . . . . . 18 5.3.3. RM Processing . . . . . . . . . . . . . . . . . . . . 18 5.3.4. Adding Additional Routing Information to a RM . . . . 20 5.4. Route Discovery . . . . . . . . . . . . . . . . . . . . . 20 5.5. Route Maintenance . . . . . . . . . . . . . . . . . . . . 21 5.5.1. Active Link Monitoring . . . . . . . . . . . . . . . . 21 5.5.2. Updating Route Lifetimes during Packet Forwarding . . 21 5.5.3. Route Error Generation . . . . . . . . . . . . . . . . 22 5.5.4. Route Error Processing . . . . . . . . . . . . . . . . 22 5.6. Unknown Message & TLV Types . . . . . . . . . . . . . . . 23 5.7. Advertising Network Addresses . . . . . . . . . . . . . . 23 5.8. Simple Internet Attachment and Gatewaying . . . . . . . . 24 5.9. Multiple Interfaces . . . . . . . . . . . . . . . . . . . 25 5.10. Packet/Message Generation Limits . . . . . . . . . . . . . 25 6. Configuration Parameters and Other Administrative Options . . 25 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 7.1. DYMO Message Type Specification . . . . . . . . . . . . . 27 7.2. Packet TLV Type Specification . . . . . . . . . . . . . . 27 7.3. Address Block TLV Specification . . . . . . . . . . . . . 28 8. Security Considerations . . . . . . . . . . . . . . . . . . . 28 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 29 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 29 10.1. Normative References . . . . . . . . . . . . . . . . . . . 29 10.2. Informative References . . . . . . . . . . . . . . . . . . 30 Chakeres & Perkins Expires April 5, 2007 [Page 2] Internet-Draft DYMO October 2006 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 31 Intellectual Property and Copyright Statements . . . . . . . . . . 32 Chakeres & Perkins Expires April 5, 2007 [Page 3] Internet-Draft DYMO October 2006 1. Overview The Dynamic MANET On-demand (DYMO) routing protocol enables reactive, multihop routing between participating nodes that wish to communicate. The basic operations of the DYMO protocol are route discovery and route management. During route discovery the originating node initiates dissemination of a Route Request (RREQ) throughout the network to find the target node. During this dissemination process, each intermediate node records a route to the originating node. When the target node receives the RREQ, it responds with a Route Reply (RREP) sent hop-by-hop toward the originating node. Each node that receives the RREP records a route to the target node, and then the RREP is unicast toward the originating node. When the originating node receives the RREP, routes have then been established between the originating node and the target node in both directions. In order to react to changes in the network topology nodes maintain their routes and monitor links over which traffic is moving. When a data packet is received for forwarding if a route is not known or the route is broken, then the source of the packet is notified. A Route Error (RERR) is sent to the packet source to indicate the current route is broken. When the source receives the RERR, it knows that it must perform route discovery if it still has packets to deliver. DYMO uses sequence numbers to ensure loop freedom [Perkins99]. Sequence numbers enable nodes to determine the order of DYMO route discovery messages, thereby avoiding use of stale routing information. 2. Applicability The DYMO routing protocol is designed for mobile ad hoc networks. DYMO handles a wide variety of mobility patterns by dynamically determining routes on-demand. DYMO also handles a wide variety of traffic patterns. In large networks DYMO is best suited for traffic scenarios where nodes communicate with only a portion of other the nodes. DYMO is applicable to memory constrained devices, since little routing state needs to be maintained. Only routing information related to active sources and destinations must be maintained, in contrast to other routing protocols that require routing information to all nodes within the autonomous system be maintained. The routing algorithm in DYMO may be operated at layers other than the network layer, using layer-appropriate addresses. Only Chakeres & Perkins Expires April 5, 2007 [Page 4] Internet-Draft DYMO October 2006 modification of the packet format is required. The routing algorithm need not change. Note that, using the DYMO algorithm with message formats (other than those specified in this document) will not be interoperable. 3. Terminology The keywords "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 [RFC2119]. This document uses some terminology from packetbb[I-D.ietf-manet- packetbb]. This document defines the following terminology: DYMO Sequence Number (SeqNum) A DYMO Sequence Number is maintained by each node. This sequence number is used by other nodes to identify the order of routing information generated by a node and to ensure loop-free routes. Hop Count (HopCnt) The number of IP hops a message or piece of information has traversed. Originating Node (OrigNode) The originating node is the node that created a DYMO Message in an effort to disseminate some information. The originating node is also referred to as a particular message's originator. Route Error (RERR) A node generates and disseminates a RERR to indicate that it does not have valid route to a one or more particular destinations. Route Reply (RREP) A RREP is used to disseminate routing information about how to reach the RREQ target node, to nodes between the RREQ target node and the RREQ originator. Route Request (RREQ) A node (the RREQ originator) generates a RREQ to discover a valid route to a particular destination, called the RREQ target node. A RREQ also provides routing information on how to reach the originator of the RREQ. Chakeres & Perkins Expires April 5, 2007 [Page 5] Internet-Draft DYMO October 2006 Target Node (TargetNode) The target node is the ultimate destination of a message. For RREQ the target node is the desired destination, the destination for which a valid route does not exist. For RREP the target node is the RREQ originator. Type-Length-Value structure (TLV) A generic way to represent information, see packetbb [I-D.ietf- manet-packetbb]. Forwarding Route A route that is used to forward data packets. Forwarding routes are generally maintained in a forwarding information base (FIB) or the kernel forwarding/routing table. 4. Data Structures 4.1. Route Table Entry The route table entry is a conceptual data structure. Implementations may use any internal representation that conforms to the semantics of a route as specified in this document. Conceptually, a route table entry has the following fields: Route.Address The IP destination address of the node associated with the routing table entry. Route.SeqNum The DYMO SeqNum associated with this routing information. Route.NextHopAddress The IP address of the next node on the path toward the Route.Address. Route.NextHopInterface The interface used to send packets toward the Route.Address. Route.Broken A flag indicating whether this Route is broken. This flag is set if the next hop becomes unreachable or in response to processing a RERR (see Section 5.5.4). The following fields are optional: Chakeres & Perkins Expires April 5, 2007 [Page 6] Internet-Draft DYMO October 2006 Route.HopCnt The number of intermediate node hops traversed before reaching the Route.Address node. Route.HopCnt assists in determining whether received routing information is superior to existing known information. Route.Prefix Indicates that the associated address is a network address, rather than a host address. The value is the length of the netmask/ prefix. If an address block does not have an associated PREFIX_LENGTH TLV [I-D.ietf-manet-packetbb] , the prefix may be considered to have a prefix length equal to the address length (in bits). Not including optional information may cause performance degradation, but it will not cause the protocol to operate incorrectly otherwise. In addition to a route table data structure, each route table entry may have several timers associated with the information. These timers/timeouts are discussed in Section 5.2.3. 4.2. DYMO Messages When describing DYMO protocol messages, it is necessary to refer to fields in several distinct parts of the overall packet. These locations include the IP or IPv6 header, the UDP header, and fields from packetbb [I-D.ietf-manet-packetbb]. This document uses the following notation conventions. Information found in the table. +----------------------------+-------------------+ | Information Location | Notational Prefix | +----------------------------+-------------------+ | IP header | IP. | | UDP header | UDP. | | packetbb message header | MsgHdr. | | packetbb message TLV | MsgTLV. | | packetbb address blocks | AddBlk. | | packetbb address block TLV | AddTLV. | +----------------------------+-------------------+ Table 1 4.2.1. Generalized MANET Packet and Message Structure DYMO messages conform to the generalized packet and message format as described in [I-D.ietf-manet-packetbb]. Here is a brief description of the format. A packet is made up of messages. A message is made up of a message header, message TLV block, and zero or more address Chakeres & Perkins Expires April 5, 2007 [Page 7] Internet-Draft DYMO October 2006 blocks. Each of the address blocks may also have an associated address TLV block. All DYMO messages specified in this document are sent using UDP to the destination port TBD. Most DYMO messages are sent with the IP destination address set to the link local multicast address LL_ALL_MANET_ROUTER unless otherwise stated. Unicast DYMO messages specified in this document are sent with the IP destination set to the Route.NextHopAddress of the route to the target node. The IP TTL (IP Hop Limit) field for DYMO messages is set to one (1) for all messages specified in this document. The length of an IP address (32 bits for IPv4 and 128 bits for IPv6) inside a DYMO message depends on the IP packet header containing the DYMO message/packet. For example, if the IP header uses IPv6 addresses then all messages and addresses contained in the payload use IPv6 addresses. In the case of mixed IPv6 and IPv4 addresses, IPv4 addresses are carried in IPv6 as specified in [RFC3513]. 4.2.2. Routing Messages (RM) - RREQ & RREP Routing Messages (RMs) are used to disseminate routing information. There are two DYMO message types that are considered to be routing messages (RMs): RREQ and RREP. They contain very similar information and function, but have slightly different processing rules. The main difference between the two messages is that RREQ messages solicit a RREP, whereas a RREP is the response to RREQ. RM creation and processing are described in Section 5.3. A RM requires the following information: IP.DestinationAddress The IP address of the packet destination. For RREQ the IP.DestinationAddress is set to LL_ALL_MANET_ROUTERS. For RREP the IP.DestinationAddress is set to the NextHopAddress toward the TargetNode. UDP.DestinationPort The UDP destination port is set to TBD. MsgHdr.HopLimit The remaining number of hops this message is allowed to traverse. Chakeres & Perkins Expires April 5, 2007 [Page 8] Internet-Draft DYMO October 2006 AddBlk.TargetNode.Address The IP address of the message target node. In a RREQ the target node is the destination for which a forwarding route does not exist and route discovery is being performed. In a RREP the target node is the RREQ originator. The target node address is the first address in the routing message. AddBlk.OrigNode.Address The IP address of the node originating this message. This address is in an address block and not in the message header to allow for address compression and additional AddTLVs. This address is the second address in the message for RREQ. AddTLV.OrigNode.SeqNum The DYMO sequence number of the originating node. A RM may optionally include the following information: AddTLV.TargetNode.SeqNum The last known DYMO sequence number of the target node. AddTLV.TargetNode.HopCnt The last known HopCnt to the target node. AddBlk.AdditionalNode.Address The IP address of an additional node that can be reached via the node adding this information. Each AdditionalNode.Address must have an associated SeqNum in the address TLV block. AddTLV.AdditionalNode.SeqNum The DYMO sequence number of an additional intermediate node's routing information. AddTLV.Node.HopCnt The number of IP hops to reach the associated Node.Address. This field is incremented at each intermediate hop, for each node except the target node's HopCnt information. AddTLV.Node.Prefix The Node.Address is a network address with a particular prefix length. Chakeres & Perkins Expires April 5, 2007 [Page 9] Internet-Draft DYMO October 2006 Example IPv4 RREQ 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 IP Header +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IP.DestinationAddress=LL_ALL_MANET_ROUTERS | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... UDP Header +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Destination Port=TBD | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... Message Header +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RREQ-type | Resv |0|0|1| msg-size=23 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | msg-hoplimit | msg-hopcnt | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... Message Body - Message TLV Block +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | msg-tlv-block-size=0 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Message Body - Address Block +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Number Addrs=2 |0|HeadLength=3 | Head : +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ : (cont) | Target.Tail | Orig.Tail | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Message Body - Address Block TLV Block +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | tlv-block-size=6 |DYMOSeqNum-type|Resv |0|1|0|0|0| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Index-start=1 | tlv-length=2 | Orig.SeqNum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1 4.2.3. Route Error (RERR) A RERR message is used to disseminate the information that a route is not available for one or more particular IP addresses. Chakeres & Perkins Expires April 5, 2007 [Page 10] Internet-Draft DYMO October 2006 RERR creation and processing are described in Section 5.5. A RERR requires the following information: IP.DestinationAddress The IP address is set to LL_ALL_MANET_ROUTERS. UDP.DestinationPort The UDP destination port is set to TBD. MsgHdr.HopLimit The remaining number of hops this message is allowed to traverse. AddBlk.UnreachableNode.Address The IP address of an UnreachableNode. Multiple unreachable addresses may be included in a RERR. A Route Error may optionally include the following information: AddTLV.UnreachableNode.SeqNum The last known DYMO sequence number of the unreachable node. If a SeqNum for an address is not included, it is assumed to be unknown. This case occurs when a node receives a message to forward for which it does not have any information in its routing table. Chakeres & Perkins Expires April 5, 2007 [Page 11] Internet-Draft DYMO October 2006 Example IPv4 RERR 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 IP Header +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IP.DestinationAddress=LL_ALL_MANET_ROUTERS | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... UDP Header +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Destination Port=TBD | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... Message Header +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RERR-type | Resv |0|0|1| msg-size=16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | msg-hoplimit | msg-hopcnt | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... Message Body +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | msg-tlv-block-size=0 |Number Addrs=1 |1|HeadLength=4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Unreachable.Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TLV-blk-size=0 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2 5. Detailed Operation 5.1. DYMO Sequence Numbers DYMO sequence numbers allow nodes to judge the freshness of routing information and ensure loop freedom. 5.1.1. Maintaining A Node's Own Sequence Number DYMO requires that each node in the network to maintain its own DYMO sequence number (OwnSeqNum), a 16-bit unsigned integer. The circumstances for a node to incrementing its OwnSeqNum are described Chakeres & Perkins Expires April 5, 2007 [Page 12] Internet-Draft DYMO October 2006 in Section 5.3. 5.1.2. Incrementing OwnSeqNum When a node increments its OwnSeqNum (as described in Section 5.3) it MUST do so by treating the sequence number value as an unsigned number. A node starts with its OwnSeqNum equal to one (1). The sequence number zero (0) is reserved. 5.1.3. OwnSeqNum Rollover If the sequence number has been assigned to be the largest possible number representable as a 16-bit unsigned integer (i.e., 65535), then the sequence number is set to 256 when incremented. Setting the sequence number to 256 allows other nodes to detect that the number has rolled over and the node has not lost its sequence number. 5.1.4. Actions After OwnSeqNum Loss A node should maintain its sequence number in persistent storage, between reboots. If a node's OwnSeqNum is lost, it must take certain actions to avoid creating routing loops. To prevent this possibility after OwnSeqNum loss a node MUST wait for at least ROUTE_DELETE_TIMEOUT before fully participating in the DYMO routing protocol. If a DYMO control message is received during this waiting period, the node SHOULD process it normally but MUST not transmit or retransmit any DYMO messages. If a data packet is received for forwarding to another destination during this waiting period, the node MUST generate a RERR message indicating that this route is not available and reset its waiting timeout. At the end of the waiting period a node sets its OwnSeqNum to one (1). The longest a node must wait is ROUTE_AGE_MAX_TIMEOUT. At the end of the maximum waiting period a node sets its OwnSeqNum to one (1) and begins participating. 5.2. DYMO Routing Table Operations 5.2.1. Judging Routing Information's Usefulness Given a route table entry (Route.SeqNum, Route.HopCnt, and Route.Broken) and new routing information for a particular node in a RM (Node.SeqNum, Node.HopCnt, and RM message type - RREQ/RREP), the quality of the new routing information is evaluated to determine its usefulness. Incoming routing information is classified as follows: Chakeres & Perkins Expires April 5, 2007 [Page 13] Internet-Draft DYMO October 2006 1. Stale If Node.SeqNum - Route.SeqNum < 0 (using signed 16-bit arithmetic) the information is stale. Using stale routing information is not allowed, since doing so might result in routing loops. (Node.SeqNum - Route.SeqNum < 0) 2. Loop-possible If Node.SeqNum == Route.SeqNum the information may cause loops if used; in this case additional information must be examined. If Route.HopCnt or Node.HopCnt is unknown or zero (0), then the routing information is loop-possible. If Node.HopCnt > Route.HopCnt + 1, then the routing information is loop-possible. Using loop-possible routing information is not allowed, otherwise routing loops may be formed. (Node.SeqNum == Route.SeqNum) AND ((Node.HopCnt is unknown) OR (Route.HopCnt is unknown) OR (Node.HopCnt > Route.HopCnt +1)) 3. Inferior If Node.SeqNum == Route.SeqNum the information may be inferior; additional information must be examined. If Node.HopCnt >= to Route.HopCnt, the current route is not Broken, and the message is a RREQ, then the new information is inferior. If Node.HopCnt > Route.HopCnt + 1, the current route is not Broken and the message is RREP, then the new information is inferior. Inferior routes will not cause routing loops if introduced, but should not be used since better information is already available. (Node.SeqNum == Route.SeqNum) AND (Route.Broken == false) AND ((Node.HopCnt > Route.HopCnt) AND (RM is RREQ)) OR ((Node.HopCnt > Route.HopCnt + 1) AND (RM is RREP))) 4. Superior Routing information that does not match any of the above criteria is loop-free and better than the information existing in the routing table. This type of information is used to update the routing table. For completeness, the following other cases are possible: Chakeres & Perkins Expires April 5, 2007 [Page 14] Internet-Draft DYMO October 2006 (Node.SeqNum - Route.SeqNum > 0) OR ((Node.SeqNum == Route.Seqnum) AND ((Node.HopCnt == Route.HopCnt + 1) OR (Node.HopCnt == Route.HopCnt)) AND (((Route.Broken == true) AND (RM is RREQ)) OR ((Route.Broken == false) AND (RM is RREP)))) OR ((Node.HopCnt < Route.HopCnt + 1) AND (Route.Broken == false)) 5.2.2. Creating or Updating a Route Table Entry with New Routing Information The route table entry is populated with the following information: 1. the Route.Address is set to Node.Address, 2. the Route.SeqNum is set to the Node.SeqNum, 3. the Route.NextHopAddress is set to the node that transmitted this DYMO RM packet (i.e., the IP.SourceAddress), 4. the Route.NextHopInterface is set to the interface that this DYMO packet was received on, 5. if known, the Route.HopCnt is set to the Node.HopCnt, 6. if known, the Route.Prefix is set to the Node.Prefix. Fields without known values are not populated with any value. Previous timers for this route table entry are removed. A timer for the minimum delete timeout (ROUTE_AGE_MIN) is set to ROUTE_AGE_MIN_TIMEOUT. A timer to indicate a recently learned route (ROUTE_NEW) is set to ROUTE_NEW_TIMEOUT. A timer for the maximum delete timeout (ROUTE_AGE_MAX). ROUTE_AGE_MAX is set to Node.AddTLV.MaxAge if included; otherwise, ROUTE_AGE_MAX is set to ROUTE_AGE_MAX_TIMEOUT. The usage of these timers and others are described in Section 5.2.3. At this point, a forwarding route should be installed. Afterward, the route can be used to send any queued data packets and forwarding any incoming data packets for Route.Address. This route also fulfills any outstanding route discovery attempts for Node.Address. 5.2.3. Route Table Entry Timeouts 5.2.3.1. Minimum Delete Timeout (ROUTE_AGE_MIN) When a node transmits a RM, other nodes expect the transmitting node Chakeres & Perkins Expires April 5, 2007 [Page 15] Internet-Draft DYMO October 2006 to have a forwarding route to the RM originator. After updating a route table entry, it should be maintained for at least ROUTE_AGE_MIN. Failure to maintain the information might result in lost messages/packets, or in the worst case scenario several duplicate messages. After the ROUTE_AGE_MIN timeout a route can safely be deleted. 5.2.3.2. Maximum Delete Timeout (ROUTE_AGE_MAX) Sequence number information is time sensitive, and must be deleted after a time in order to avoid conflicts due to reboots and rollovers. When a node has lost its sequence number (e.g, due to daemon reboot or node replacement) the node must wait until routing information associated with its IP address and sequence number are no longer maintained by other nodes in the network to ensure loop-free routing. After the ROUTE_AGE_MAX timeout a route must be deleted. All information about the route is deleted upon ROUTE_AGE_MAX timeout. If a forwarding route exists it is also removed. 5.2.3.3. New Information Timeout (ROUTE_NEW) As time progresses the likelihood that a route remains intact decreases, if the network nodes are mobile. Maintaining and using old routing information can lead to many DYMO messages and excess route discovery delay. After the ROUTE_NEW timeout if the route has not been used, a timer for deleting the route (ROUTE_DELETE) is set to ROUTE_DELETE_TIMEOUT. 5.2.3.4. Recently Used Timeout (ROUTE_USED) When a route is used to forward data packets, this timer is set to expire after ROUTE_USED_TIMEOUT. This operation is also discussed in Section 5.5.2. If a route has not been used recently, then a timer for ROUTE_DELETE is set to ROUTE_DELETE_TIMEOUT. 5.2.3.5. Delete Information Timeout (ROUTE_DELETE) As time progresses the likelihood that old routing information is useful decreases, especially if the network nodes are mobile. Therefore, old information should be deleted. After the ROUTE_DELETE timeout, the routing table entry should be Chakeres & Perkins Expires April 5, 2007 [Page 16] Internet-Draft DYMO October 2006 deleted. If a forwarding route exists, it should also be removed. 5.3. Routing Messages 5.3.1. RREQ Creation When a node creates a RREQ it SHOULD increment its OwnSeqNum by one (1) according to the rules specified in Section 5.1.2. Incrementing OwnSeqNum will ensure that all nodes with existing routing information to consider this new information fresh. If the sequence number is not incremented, certain nodes might not consider this information useful if they have better information already. First, the node adds the AddBlk.TargetNode.Address to the RM. If a previous value of the TargetNode.SeqNum is known (from a routing table entry), it should be placed in AddTLV.TargetNode.SeqNum. If a TargetNode.SeqNum is not included, it is assumed to be unknown by processing nodes. Similarly, if a previous value of the TargetNode.HopCnt is known, it should be placed in AddTLV.TargetNode.HopCnt. Otherwise, the AddTLV.TargetNode.HopCnt is not included and assumed unknown by processing nodes. These AddTLVs associated with the target node should be set to improve protocol efficiency, but they may be omitted. Next, the node adds AddBlk.OrigNode.Address to the RM and the AddTLV.OrigNode.SeqNum (OwnSeqNum) in an address block TLV. The OrigNode.Address is this node's primary addresses/identifier, and it must be a routable IP address. This information will be used by nodes to create a route toward the OrigNode and enable delivery of a RREP. Other AddTLVs for the OrigNode should be set to improve protocol efficiency, but they may be omitted. If OrigNode.HopCnt is included it is set to zero (0). The MsgHdr.HopCnt is set to zero (0). The MsgHdr.HopLimit should be set to NET_DIAMETER, but may be set smaller. For RREQ, the MsgHdr.HopLimit may be set in accordance with an expanding ring search as described in [RFC3561] to limit the RREQ propagation to a subset of the network and possibly reduce route discovery overhead. The IP.DestinationAddress for RREQ is set to the LL_ALL_MANET_ROUTERS. Chakeres & Perkins Expires April 5, 2007 [Page 17] Internet-Draft DYMO October 2006 5.3.2. RREP Creation When a node creates a RREP in response to a RREQ, it increments its OwnSeqNum by one (1) according to the rules specified in Section 5.1.2. If OwnSeqNum is not incremented the routing information might be considered stale. In this case, the RREP would not reach the originating node. Note: We are currently discussing and investigating mechanisms to avoid incrementing the sequence number before issuing a route reply. An update to this behavior will likely happen in the next revision. Avoiding incrementation of the sequence number when issuing a RREP is an important mechanism to reduce the unnecessary devaluing of good routing information, and the ability to issue intermediate node replies. Further when intermediate node replies are coupled with expanding ring search, route discovery cost can be further reduced. The node then adds the AddBlk.TargetNode.Address to the RREP. The TargetNode.Address is copied from the incoming RREQ AddBlk.OrigNode.Address. Next, the node adds the AddBlk.OrigNode.Address to the RREP and the AddTLV.OrigNode.SeqNum (OwnSeqNum) in an address block TLV. The OrigNode.Address is copied from the incoming RREQ AddBlk.TargetNode.Address. Other AddTLVs for the OrigNode and TargetNode should be set to improve protocol efficiency, but they may be omitted. If OrigNode.HopCnt is included it is set to zero (0). The MsgHdr.HopCnt is set to zero (0). The MsgHdr.HopLimit is set to NET_DIAMETER. The IP.DestinationAddress for RREP is set to the IP address of the Route.NextHopAddress for the route to the RREP TargetNode. 5.3.3. RM Processing When a RM is received the MsgHdr.HopLimit is decremented by one (1) and MsgHdr.HopCnt is incremented by one (1). For each address (except the TargetNode) in the RM that includes AddTLV.HopCnt information, the AddTLV.HopCnt information is incremented by one (1). Next, this node checks whether its routing table has an entry to the AddBlk.OrigNode.Address using longest-prefix matching [RFC1812]. If a route does not exist, the new routing information is considered Chakeres & Perkins Expires April 5, 2007 [Page 18] Internet-Draft DYMO October 2006 fresh and a new route table entry is created and updated as described in Section 5.2.2. If a route table entry does exists, the new node's information is compared with the route table entry following the procedure described in Section 5.2.1. If the new node's routing information is considered superior, the route table entry is updated as described in Section 5.2.2. After processing the OrigNode's routing information, then each address that is not the TargetNode should be considered for creating and updating routes. Creating and updating routes to other nodes can eliminate RREQ for those IP destinations, in the event that data needs to be forwarded to the IP destination(s) in the near future. For each of the additional addresses considered, if the routing table does not have a matching route using longest-prefix matching, then a route is created and updated as described in Section 5.2.2. If a route table entry exists, the new node's information is compared with the route table entry following the procedure described in Section 5.2.1. If the new node's routing information is considered superior, the route table entry is updated as described in Section 5.2.2. If the routing information for an AdditionalNode.Address is not considered superior, then it is removed from the RM. Removing this information ensures that the information is not propagated. At this point, if the routing information for the OrigNode was not superior then this RM should be discarded and no further processing of this message is performed. If the receiving node is the TargetNode AND this RM is a RREQ, then this node responds with a RREP. The procedure for creating a new RREP is described in Section 5.3.2. After processing a RM or creating a new RM, a node can append additional routing information to the RM, according to the procedure described in Section 5.3.4. The additional routing information can help reduce route discoveries at the expense of increased message size. If this RM's MsgHdr.HopLimit is greater than one (1), this node is not the TargetNode, AND this RM is a RREQ, then the current RM (altered by the procedure defined above) is sent to the LL_ALL_MANET_ROUTERS IP.DestinationAddress. If this RM's MsgHdr.HopLimit is greater than one (1), this node is not the TargetNode, AND this RM is a RREP, then the current RM is sent to the Route.NextHopAddress for the RREP's TargetNode.Address. Chakeres & Perkins Expires April 5, 2007 [Page 19] Internet-Draft DYMO October 2006 If no forwarding route exists to Target.Address, then a RERR is issued to the originator of the RREP. If this node is the TargetNode of the RM, the current RM is not retransmitted. 5.3.4. Adding Additional Routing Information to a RM Appending routing information can alleviate route discovery attempts to the nodes whose information is included, if other nodes use this information to update their routing tables. Nodes can append routing information to a RM, and should if the node believes that this additional routing information will alleviate future RREQ. This option should be administratively configured. Prior to appending its own address to a RM, a node should increment its OwnSeqNum as defined in Section 5.1.2. If OwnSeqNum is not incremented the appended routing information might not be considered fresh, when received by nodes with existing routing information. Incrementation of the sequence number when appending information to an RM in transit should be administratively configured. If included the Node.HopCnt for this node is included, it is set to zero (0). Additional information about the address(es) can also be appended, such as a PREFIX_LENGTH AddTLV. 5.4. Route Discovery A node creates and sends a RREQ (described in Section 5.3.1) to discover a route to a particular destination (TargetNode) for which it does not currently have a forwarding route. After issuing a RREQ, the OrigNode waits for a route to be created to the TargetNode. If a route is not created within RREQ_WAIT_TIME, this node may again try to discover a route by issuing another RREQ. To reduce congestion in a network, repeated attempts at route discovery for a particular target node should utilize an exponential backoff. For example, the first time a node issues a RREQ, it waits RREQ_WAIT_TIME for a route to the target node. If a route is not found within that time, the node MAY send another RREQ. If a route is not found within two (2) times the current waiting time, another RREQ may be sent, up to a total of RREQ_TRIES. For each additional attempt, the waiting time for the previous RREQ is multiplied by two (2) so that the waiting time conforms to a binary exponential Chakeres & Perkins Expires April 5, 2007 [Page 20] Internet-Draft DYMO October 2006 backoff. Data packets awaiting a route should be buffered. This buffer should have a fixed limited size (BUFFER_SIZE_PACKETS or BUFFER_SIZE_BYTES) and older data packets should be discarded first. If a route discovery has been attempted RREQ_TRIES times without receiving a route to the target node, all data packets destined for the corresponding target node are dropped from the buffer and a Destination Unreachable ICMP message should be delivered to the application. 5.5. Route Maintenance A RERR MUST be issued if a data packet is received and it cannot be delivered to the next hop when no forwarding route exists; RERR generation is described in Section 5.5.3. In addition to inability to deliver a data packet, A RERR should be issued immediately after detecting a broken link of an forwarding route to quickly notify nodes that a link break occurred and that certain routes are no longer available. If the route with the broken link has not been used recently (indicated by ROUTE_USED), the RERR should not be generated. 5.5.1. Active Link Monitoring Nodes MUST monitor next hop links on forwarding routes. This monitoring can be accomplished by one or several mechanisms, including: o Link layer feedback o Neighborhood discovery [I-D.ietf-manet-nhdp] o Route timeout o Other monitoring mechanisms or heuristics Upon detecting a link break (or an unreachable next hop) the detecting node must remove the affected forwarding routes (those with an unreachable next hop). The node also flags these routes as Broken. For each broken route a timer for ROUTE_DELETE is set to ROUTE_DELETE_TIMEOUT. 5.5.2. Updating Route Lifetimes during Packet Forwarding To avoid removing forwarding routes that are being used, a node Chakeres & Perkins Expires April 5, 2007 [Page 21] Internet-Draft DYMO October 2006 SHOULD set a timeout (ROUTE_USED) to ROUTE_USED_TIMEOUT for the route to the IP.SourceAddress upon receiving a data packet. If a timer for ROUTE_DELETE is set, it is removed. To avoid removing forwarding routes that are being used, a node SHOULD set a timeout (ROUTE_USED) to ROUTE_USED_TIMEOUT for the route to the IP.DestinationAddress upon sending a data packet. If a timer for ROUTE_DELETE is set, it is removed. 5.5.3. Route Error Generation When a data packet is received for a destination without a valid route table entry, a RERR MUST be generated. When a RREP is being transmitted and no forwarding route to the TargetNode exists, a RERR MUST be generated. A RERR informs the IP.SourceAddress or RREP.OrigNode.Address that the route does not exist, and a route is not available through this node. When creating a new RERR, the address of first unreachable node (IP.DestinationAddress from the data packet or RREP.TargetNode.Address) is inserted. If a value for the unreachable node's SeqNum (AddTLV.UnreachableNode.SeqNum) is known, it should be placed in the RERR. The MsgHdr.HopLimit is set to NET_DIAMETER. The MsgHdr.HopCnt is set to one (1). Additional UnreachableNodes that require the same unavailable link (routes with the same Route.NextHopAddress and Route.NextHopInterface) may be added to the RERR. The SeqNum if known should also be included. Appending UnreachableNode information notifies each processing node of additional routes that are no longer available. This option should be administratively configured. If SeqNum information is not known or not included in the RERR, all nodes processing the RERR will assume their routing information associated with the UnreachableNode is no longer valid. The RERR is sent to the IP.DestinationAddress LL_ALL_MANET_ROUTERS. Sending the RERR to the LL_ALL_MANET_ROUTERS address notifies nearby nodes that might depend on the now broken link. The packet or message that forced generation of this RERR is discarded. 5.5.4. Route Error Processing When a node processes a RERR, it processes each UnreachableNode's information. The processing node removes the forwarding route and sets the broken flag for each UnreachableNode.Address found using Chakeres & Perkins Expires April 5, 2007 [Page 22] Internet-Draft DYMO October 2006 longest prefix matching that meet all of the following conditions: 1. The Route.NextHopAddress is the same as the RERR IP.SourceAddress. 2. The Route.NextHopInterface is the same as the interface on which the RERR was received. 3. The Route.SeqNum is zero (0), unknown, OR the UnreachableNode.SeqNum is zero (0), unknown, OR UnreachableNode.SeqNum - Route.SeqNum <= 0 (using signed 16-bit arithmetic). Each UnreachableNode that did not result in a broken route is removed from the RERR, since propagation of this information will not result in any benefit. Any other information (AddTLVs) associated with the removed address(es) is also removed. If no UnreachableNode addresses remain in the RERR, no other processing is required and the RERR is discarded. If this RERR's MsgHdr.HopLimit is greater than one (1) and at least one unreachable node address remains in the RERR, then the updated RERR is sent to the IP.DestinationAddress LL_ALL_MANET_ROUTERS. 5.6. Unknown Message & TLV Types If a message with an unknown type is received, the message is discarded. If a message contains TLVs of an unknown type, a node ignores these during processing. The processing node can remove these TLVs from any resulting transmitted messages. The behavior for unknown TLV types should be administratively configured. 5.7. Advertising Network Addresses Any node can advertise a network address by using a PREFIX_LENGTH TLV [I-D.ietf-manet-packetbb]. Any nodes (other than the advertising node) within the advertised prefix SHOULD NOT participate in the DYMO protocol directly and these nodes MUST be reachable by forwarding packets to the node advertising connectivity. Nodes other than the advertising node that do participate in DYMO must forward the DYMO control packets to the advertising node. For example, A.B.C.1 with a prefix length of 24 indicates all nodes with the matching A.B.C.X are reachable through the node with address A.B.C.1. Chakeres & Perkins Expires April 5, 2007 [Page 23] Internet-Draft DYMO October 2006 5.8. Simple Internet Attachment and Gatewaying Simple Internet attachment consists of a network of MANET nodes connected to the Internet via a single Internet gateway node. The gateway is responsible for responding to RREQs for target nodes outside its configured DYMO prefix, as well as delivering packets to destinations outside the MANET. /--------------------------\ / Internet \ \ / \------------+-------------/ Gateway's | Advertised | A.B.C.X Prefix | +-----+-----+ | DYMO | /------| Internet |------\ / | Gateway | \ / | A.B.C.1 | \ | +-----------+ | | DYMO Region | | | | +------------+ | | | DYMO Node | | | | A.B.C.2 | | | +------------+ | | +------------+ | | | DYMO Node | | | | A.B.C.3 | | \ +------------+ / \ / \-------------------------/ Figure 7: Simple Internet Attachament Example DYMO nodes wishing to be reachable from nodes in the Internet MUST have IP addresses within the gateway's configured and advertised prefix. Given a node with a globally routeable address or care-of address handled by the gateway, the gateway is responsible for routing and forwarding packets received from the Internet destined for nodes inside its MANET. When nodes within the MANET want to send messages to nodes in the Internet, they simply issue RREQ for those IP.DestinationAddresses. The gateway is responsible for responding to RREQ on behalf of the Internet destinations and maintaining their associated sequence numbers. Chakeres & Perkins Expires April 5, 2007 [Page 24] Internet-Draft DYMO October 2006 For an Internet gateway and other nodes that maintain the sequence number on behalf of other nodes, these routers must be administratively configured to know the IP addresses for which they must generate DYMO messages and maintain OwnSeqNum. 5.9. Multiple Interfaces DYMO will often be used with multiple interfaces; therefore, the particular interface over which packets arrive must be known whenever a packet is received. Whenever a new route is created, the interface through which the Route.Address can be reached is also recorded in the route table entry. When multiple interfaces are available, a node transmitting a packet with IP.DestinationAddress set to LL_ALL_MANET_ROUTERS SHOULD send the packet on all interfaces that have been configured for DYMO operation. 5.10. Packet/Message Generation Limits To avoid congestion, a node's rate of packet/message generation should be limited. The rate and algorithm for limiting messages is left to the implementor and should be administratively configured. Messages should be discarded in the following order of preferences RREQ, RREP, and finally RERR. 6. Configuration Parameters and Other Administrative Options Suggested Parameter Values +------------------------------+------------------------+ | Name | Value | +------------------------------+------------------------+ | NET_DIAMETER | 10 hops | | NET_TRAVERSAL_TIME | 1000 milliseconds | | ROUTE_TIMEOUT | 5 seconds | | ROUTE_AGE_MIN_TIMEOUT | NET_TRAVERSAL_TIME | | ROUTE_AGE_MAX_TIMEOUT | 60 seconds | | ROUTE_NEW_TIMEOUT | ROUTE_TIMEOUT | | ROUTE_USED_TIMEOUT | ROUTE_TIMEOUT | | ROUTE_DELETE_TIMEOUT | 2 * ROUTE_TIMEOUT | | ROUTE_RREQ_WAIT_TIME | 2 * NET_TRAVERSAL_TIME | | RREQ_TRIES | 3 tries | | UNICAST_MESSAGE_SENT_TIMEOUT | 1 second | +------------------------------+------------------------+ Table 2 Chakeres & Perkins Expires April 5, 2007 [Page 25] Internet-Draft DYMO October 2006 These suggested values work well for small and medium well connected networks with infrequent topology changes. These parameters should be administratively configured for the network where DYMO is used. Ideally, for networks with frequent topology changes the DYMO parameters should be adjusted using either experimentally determined values or dynamic adaptation. For example, in networks with infrequent topology changes ROUTE_USED_TIMEOUT may be set to a much larger value. In addition to the parameters above several administrative options exist. The following table enumerates several of the options and suggested values. Suggested Options Settings +-------------------------------------+----------------------------+ | Name | Value | +-------------------------------------+----------------------------+ | RESPONSIBLE_ADDRESSES | Self or Prefix | | DYMO_INTERFACES | User Specified | | INCLUDE_INFORMATION | Yes-SeqNum,HopCnt,Prefix | | APPEND_ADDRESS | Yes - RREQ & RREP | | APPEND_OWN_ADDRESS_INCREMENT_SEQNUM | Yes for RREQ | | GENERATE_RERR_IMMEDIATELY | No | | RERR_INCLUDE_ALL_UNREACHABLES | Yes | | UNKNOWN_TYPE_HANDLING | Ignore | | BUFFER_SIZE_PACKETS | 50 packets | | BUFFER_SIZE_BYTES | 1500 * BUFFER_SIZE_PACKETS | +-------------------------------------+----------------------------+ Table 3 7. IANA Considerations DYMO requires a UDP port number to carry protocol packets - TBD. DYMO also requires the link-local multicast address LL_ALL_MANET_ROUTERS; IPv4 TBD, IPv6 TBD [I-D.chakeres-manet-iana]. This section specifies several messages types, message tlv-types, and address tlv-types. Future types will be allocated using standard actions as described in [RFC2434]. Chakeres & Perkins Expires April 5, 2007 [Page 26] Internet-Draft DYMO October 2006 7.1. DYMO Message Type Specification DYMO Message Types +------------------------+----------+ | Name | Type | +------------------------+----------+ | Route Request (RREQ) | 10 - TBD | | Route Reply (RREP) | 11 - TBD | | Route Error (RERR) | 12 - TBD | +------------------------+----------+ Table 4 7.2. Packet TLV Type Specification Packet TLV Types +-------------------+------+--------+-------------------------------+ | Name | Type | Length | Value | +-------------------+------+--------+-------------------------------+ | Unicast Response | 10 - | 0 | Indicates to the processing | | Request | TBD | | node that the previous hop | | | | | (IP.SourceAddress) expects a | | | | | unicast message within | | | | | UNICAST_MESSAGE_SENT_TIMEOUT. | | | | | Any unicast packet will serve | | | | | this purpose, and it MAY be | | | | | an ICMP REPLY message. If a | | | | | message is not sent, then the | | | | | previous hop may assume that | | | | | the link is unidirectional | | | | | and may blacklist the link to | | | | | this node. | +-------------------+------+--------+-------------------------------+ Table 5 Chakeres & Perkins Expires April 5, 2007 [Page 27] Internet-Draft DYMO October 2006 7.3. Address Block TLV Specification Address Block TLV Types +----------------+------+---------+---------------------------------+ | Name | Type | Length | Value | +----------------+------+---------+---------------------------------+ | DYMOSeqNum | 10 - | 16 bits | The DYMO sequence num | | | TBD | | associated with this address. | | | | | The sequence number may be the | | | | | last known sequence number. | | HopCount | 11 - | 8 bits | The number of hops traversed by | | | TBD | | the information associated with | | | | | this address. | | MaxAge | 12 - | Any | The maximum number of | | | TBD | length | milliseconds that the | | | | | associated routing information | | | | | can be kept before being | | | | | deleted. | +----------------+------+---------+---------------------------------+ Table 6 8. Security Considerations Currently, DYMO does not specify any special security measures. Routing protocols, however, are prime targets for impersonation attacks. In networks where the node membership is not known, it is difficult to determine the occurrence of impersonation attacks, and security prevention techniques are difficult at best. However, when the network membership is known and there is a danger of such attacks, DYMO messages must be protected by the use of authentication techniques, such as those involving generation of unforgeable and cryptographically strong message digests or digital signatures. While DYMO does not place restrictions on the authentication mechanism used for this purpose, IPsec Authentication Message (AH) is an appropriate choice for cases where the nodes share an appropriate security association that enables the use of AH. In particular, RM messages SHOULD be authenticated to avoid creation of spurious routes to a destination. Otherwise, an attacker could masquerade as that destination and maliciously deny service to the destination and/or maliciously inspect and consume traffic intended for delivery to the destination. RERR messages SHOULD be authenticated in order to prevent malicious nodes from disrupting active routes between communicating nodes. Chakeres & Perkins Expires April 5, 2007 [Page 28] Internet-Draft DYMO October 2006 If the mobile nodes in the ad hoc network have pre-established security associations, the purposes for which the security associations are created should include that of authorizing the processing of DYMO control packets. Given this understanding, the mobile nodes should be able to use the same authentication mechanisms based on their IP addresses as they would have used otherwise. 9. Acknowledgments DYMO is a descendant of the design of previous MANET reactive protocols, especially AODV [RFC3561] and DSR [Johnson96]. Changes to previous MANET reactive protocols stem from research and implementation experiences. Thanks to Elizabeth Belding-Royer for her long time authorship of DYMO. Additional thanks to Luke Klein- Berndt, Pedro Ruiz, Fransisco Ros, Koojana Kuladinithi, Ramon Caceres, Thomas Clausen, Christopher Dearlove, and Seung Yi for reviewing of DYMO, as well as several specification suggestions. 10. References 10.1. Normative References [I-D.ietf-manet-packetbb] Clausen, T., "Generalized MANET Packet/Message Format", draft-ietf-manet-packetbb-02 (work in progress), July 2006. [RFC1812] Baker, F., "Requirements for IP Version 4 Routers", RFC 1812, June 1995. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998. [RFC3513] Hinden, R. and S. Deering, "Internet Protocol Version 6 (IPv6) Addressing Architecture", RFC 3513, April 2003. [RFC3561] Perkins, C., Belding-Royer, E., and S. Das, "Ad hoc On- Demand Distance Vector (AODV) Routing", RFC 3561, July 2003. Chakeres & Perkins Expires April 5, 2007 [Page 29] Internet-Draft DYMO October 2006 10.2. Informative References [I-D.chakeres-manet-iana] Chakeres, I., "MANET IANA Needs", draft-chakeres-manet-iana-01 (work in progress), September 2006. [I-D.ietf-manet-nhdp] Clausen, T., "MANET Neighborhood Discovery Protocol (NHDP)", draft-ietf-manet-nhdp-00 (work in progress), June 2006. [Johnson96] Johnson, D. and D. Maltz, "Dynamic Source Routing (DSR) in Ad hoc Networks", In Mobile Computing, Chapter 5, pp. 153- 181, 1996. [Perkins99] Perkins, C. and E. Belding-Royer, "Ad hoc On-Demand Distance Vector (AODV) Routing", Proceedings of the 2nd IEEE Workshop on Mobile Computing Systems and Applications, New Orleans, LA, pp. 90-100, February 1999. Chakeres & Perkins Expires April 5, 2007 [Page 30] Internet-Draft DYMO October 2006 Authors' Addresses Ian Chakeres Boeing Phantom Works The Boeing Company P.O. Box 3707 Mailcode 7L-49 Seattle, WA 98124-2207 USA Email: ian.chakeres@gmail.com Charlie Perkins Nokia Research Center 313 Fairchild Drive Mountain View, CA 94043 USA Phone: +1-650-625-2986 Fax: +1-650-625-2502 Email: charles.perkins@nokia.com Chakeres & Perkins Expires April 5, 2007 [Page 31] Internet-Draft DYMO October 2006 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. 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 (2006). 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. Chakeres & Perkins Expires April 5, 2007 [Page 32]