MANET Autoconfiguration (AUTOCONF) I. Chakeres Internet-Draft Boeing Intended status: Informational J. Macker Expires: September 3, 2007 Naval Research Laboratory T. Clausen LIX, Ecole Polytechnique March 2, 2007 Mobile Ad hoc Network Architecture draft-ietf-autoconf-manetarch-01 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 September 3, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Abstract This document discusses Mobile Ad hoc NETworks (MANETs). It introduces basic MANET terms, characteristics, and challenges. This document also defines several MANET entities and architectural concepts. Chakeres, et al. Expires September 3, 2007 [Page 1] Internet-Draft MANET Architecture March 2007 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Borrowed Terminology . . . . . . . . . . . . . . . . . . . 3 2.2. MANET Terminology . . . . . . . . . . . . . . . . . . . . 5 3. MANET Motivation Discussion . . . . . . . . . . . . . . . . . 6 4. MANET Interface Characteristics . . . . . . . . . . . . . . . 7 4.1. Qualities - Wireless, Mobile, Ad hoc . . . . . . . . . . . 7 4.2. Challenges . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2.1. Semi-Broadcast Interface . . . . . . . . . . . . . . . 8 4.2.2. Fuzzy Neighbor Relationship & Extended Neighborhood . 9 4.2.3. MANET Membership . . . . . . . . . . . . . . . . . . . 9 5. Addressing, aka the MANET Prefix Model . . . . . . . . . . . . 10 6. MANETs' Place in the Network Stack . . . . . . . . . . . . . . 13 7. Cross Layering . . . . . . . . . . . . . . . . . . . . . . . . 14 8. Deployment Taxonomy . . . . . . . . . . . . . . . . . . . . . 15 8.1. Service Availability . . . . . . . . . . . . . . . . . . . 15 8.2. Number of Peer MANET Routers . . . . . . . . . . . . . . . 15 8.3. Example Deployments . . . . . . . . . . . . . . . . . . . 16 9. Security Considerations . . . . . . . . . . . . . . . . . . . 16 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16 12. Informative References . . . . . . . . . . . . . . . . . . . . 17 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18 Intellectual Property and Copyright Statements . . . . . . . . . . 20 Chakeres, et al. Expires September 3, 2007 [Page 2] Internet-Draft MANET Architecture March 2007 1. Introduction A Mobile Ad hoc NETwork (MANET) consists of a loosely connected set of MANET nodes. Each MANET node embodies a MANET router and zero or more hosts. These routers organize and maintain a routing structure among themselves. These routers usually communicate over wireless links and may be mobile. MANETs' characteristics create challenges in several areas, and often require protocol extensions or new MANET protocols altogether. This document is focused on IP networking, though many of MANETs' concepts and issues span the protocol stack. This document is meant to complement [RFC2501] in describing and defining MANET. 2. Terminology 2.1. Borrowed Terminology Much of the terminology in this document was borrowed from existing documents, to list a few [RFC1812], [RFC2328], [RFC2453], [RFC2460], [RFC2461], [RFC3513], [RFC3753], [I-D.iab-multilink-subnet-issues], [I-D.templin-autoconf-dhcp], and [I-D.ietf-ipv6-2461bis]. Note that the original text for the terms is often modified, though we have attempted to maintain the same meaning. In the future, terms defined elsewhere will likely be cited instead of included. This document employs the following definitions: Node any device (router or host) that implements IP. Router (RT) a node that forwards IP packets not explicitly addressed to itself. Host any node that is not a router, i.e. it does not forward packets addressed to others. Link A communications facility at a layer below IP, over which nodes exchange IP packets directly without decrementing IP TTL (Hop Limit). Chakeres, et al. Expires September 3, 2007 [Page 3] Internet-Draft MANET Architecture March 2007 Asymmetric Reachability A link where non-reflexive and/or non-transitive reachability is part of normal operation. Non-reflexive reachability means packets from X reach Y but packets from Y don't reach X. Non- transitive reachability means packets from X reach Y, and packets from Y reach Z, but packets from X don't reach Z. Many radio/ wireless interfaces exhibit these properties. Neighbor If node X can directly exchange IP packets with node Y, then node Y is node X's neighbor. Packet reception characteristics are often used to assist devices in determining the quality of neighbors' communication. Interface A node's point of attachment to a communication link. Broadcast Interface An interface supporting many attached nodes, together with the capability to address a single link layer message to all of the attached nodes (broadcast). The set of nodes receiving a given physical broadcast message are the neighbors of the node originating the message. Full-Broadcast Interface (FBI) A broadcast interface with reflexive and transitive reachability. All nodes on the interface can send and receive IP packets directly, all nodes are symmetric neighbors. An Ethernet segment is an example of a FBI. Semi-Broadcast Interface (SBI) A broadcast interface that may exhibit non-reflexive and/or non- transitive reachability. A FBI is a special case of SBI. Multiple access wireless radio interfaces are often SBI. Site a set of one or more links. Flooding The process of forwarding or distributing information to all devices with in a bounded region. Border Router (MBR) a router that participates in multiple routing regions, and often multiple routing protocols. A BR forms a border between its multiple routing regions. A BR is responsible for presenting a consistent picture of the nodes reachable through itself to each routing region. A BR determines the routing information to Chakeres, et al. Expires September 3, 2007 [Page 4] Internet-Draft MANET Architecture March 2007 propagate between different routing regions. 2.2. MANET Terminology In MANET there are two important entities. We define the following entities: MANET Node (MN) a MANET node embodies a MANET router and zero or more hosts, as illustrated in Figure 1. MANET Router (MR) an entity that has one or more MANET interfaces and that engages in a MANET routing protocol. A MANET router may also have zero or more classic IP interfaces to which hosts may connect. <~~~~~~+~~~~~~> MANET | INTERFACE ''''''''''|'''''''''' ' +-------|------+ ' ' | MANET Router | ' ' +-------+-+----+ ' ' : : ' ' MANET : +---+ ' ' Node : | H | ' ============ ' : +---+ ' = : = '''''''''':'''''''''' =CLASSIC IP= +......+......+ =INTERFACES= : : ============ +-+-+ +-+-+ | H | * * * | H | +---+ +---+ Figure 1: MANET Node In MANET there are several architectural scopes. We define the following scopes: MANET Neighbors a set of MANET routers that is reachable in one hop over MANET interface(s). Chakeres, et al. Expires September 3, 2007 [Page 5] Internet-Draft MANET Architecture March 2007 MANET N-Neighborhood a set of MANET routers that is reachable in a N hops. These routers usually have a large number of common neighbors and may directly compete for the same shared wireless resources. MANET a set of MANET routers that is reachable via one or more hops. If a link forms between two previously separated MANET routers or MANETs, the two MANETs will merge to form a single larger MANET. Similarly, if a critical link between two MANET routers is lost the MANET will partition into two MANETs. When discussing MANETs' connectivity to other networks, like the Internet, a MANET is bounded by border routers (BR). That is, a MANETs' BR form a border between a MANET and other routing regions. 3. MANET Motivation Discussion The Internet Protocol (IP) core design tenets -- connectionless networking and packet-based forwarding -- are ideally suited for use in highly dynamic contexts, such as MANETs. Yet, some additional functionality is required to meet the unique challenges and opportunities present in MANETs. The initial motivation for MANETs was called Packet Radio (PR) networking [FL01]. In PR, each router is equipped with a single SBI. This configuration is the simplest MANET router configuration. Each router may be mobile, and the routers may be or may become spatially distributed such that all routers cannot communicate directly. That is, two routers might require one or more other intermediate routers to forward (route) packets on their behalf. In the example shown in Figure 2, for RT1 to send packets to RT3, the intermediary RT2 must relay the packets. This implies that RT2 must receive the packet from RT1 on its interface and determine that it must retransmit the packet over the same interface as the one where the packet was received, in order for the packet to reach RT3. This example also illustrates how SBIs differ from FBIs: from the point of view of RT2, both RT1 and RT3 are neighbors, whereas RT1 and RT3 are not themselves neighbors with one another. Chakeres, et al. Expires September 3, 2007 [Page 6] Internet-Draft MANET Architecture March 2007 Communication Range <~~~~~~+~~~~~~> <~~~~~~+~~~~~~> Single | <~~~~~~+~~~~~~> | SBI +-|-+ +-|-+ +-|-+ |RT1| |RT2| |RT3| +---+ +---+ +---+ Figure 2: Basic MANET Network In addition to addressing nodes' asymmetric reachability other challenges exist. In PR networks, shared wireless resources result in interdependence between nearby nodes, and these nodes often communicate directly or indirectly. The dynamic wireless interface characteristics and node mobility often manifest as frequent network topology changes. PR networks also lead to several other architecture related challenges. One challenge was to attach these PR networks to other networks, especially fixed networks like the ARPANET. Another related challenge was how to deal with the large disparity between different node and interface characteristics. These PR network challenges helped stimulate the Internet Protocol; an architecture based on connectionless networking and packet-based forwarding that enables interconnection of heterogeneous devices over heterogeneous interfaces. 4. MANET Interface Characteristics Inheriting from Packet Radio as described above, a chief particularity of MANETs are the characteristics and qualities of MANET interfaces, and the challenges these entail for protocol design and development. 4.1. Qualities - Wireless, Mobile, Ad hoc In MANET several qualities impact protocol design. The most fundamental qualities are wireless interface characteristics, mobility, and ad hoc interaction. Wireless interfaces exhibit challenging characteristics when compared with wired interfaces. Many protocols (e.g. neighbor discovery) do not operate in wireless networks with asymmetric reachability. Wireless interfaces also exhibit time varying performance that can significantly impact local communication. Chakeres, et al. Expires September 3, 2007 [Page 7] Internet-Draft MANET Architecture March 2007 Mobility can also exacerbates wireless networking issues, making it more challenging to attain, establish, and maintain network neighbor relationships between nodes. Ad hoc networking further compounds problems by allowing nodes to join and leave the network, or even form new networks, at will. 4.2. Challenges MANETs characteristics result in many challenges. These challenges reveal themselves in many forms, and MANET specific protocols must often be developed. 4.2.1. Semi-Broadcast Interface Given a wireless SBI (with non-transitive and non-reflexive properties) and spatially distributed nodes, each node may have a different unique partial view of the MANET. That is, each node may have a different set of adjacent nodes. Communication Range <~~~~~~+~~~~~~> <~~~~~~+~~~~~~> Single | <~~~~~~+~~~~~~> | SBI +-|-+ +-|-+ +-|-+ |RT1| |RT2| |RT3| +---+ +---+ +---+ RT1 RT2 RT3 ------------------------- Neighbors * RT2 RT1 RT2 * RT3 Figure 3: Semi-Broadcast Interface (SBI) Neighbors The possibly unique set of adjacent nodes in each node often requires nodes to forward packets out the same wireless interface as the one over which they were received. Topologically, this act of forwarding out the same interface causes a packet to reach a possibly different set of nodes by traversing the wireless communication medium in a new location. An example is provided in Figure 3, where each router is capable of reaching a different set of routers. The act of forwarding packets out of the same interface as the one over which they were received often results in duplicate IP packets being received at nodes with more than one neighbor, while also Chakeres, et al. Expires September 3, 2007 [Page 8] Internet-Draft MANET Architecture March 2007 reaching a new subset of nodes. 4.2.2. Fuzzy Neighbor Relationship & Extended Neighborhood Defining the process of determining a neighbor's existence, continued existence, and loss of existence is a fundamental challenge in MANETs. Neighbors are hard to define due to the expected interface characteristics: non-transitive, non-reflexive, time varying, and other wireless properties. Historically, two nodes are either neighbors or not neighbors and several simple mechanisms have been used to determine a neighbor relationship: single packet reception, acceptable loss rates, and simple handshakes. In wireless networks the types of neighbor relationships expand, as do the mechanisms to detect and maintain the state of such relationships. In wireless networks, nodes may often have non-reflexive (also often seen called unidirectional or asymmetric) communication links. Wireless networks also experience significant time varying packet delivery, so simple loss rates may not be sufficient to define a neighbor relationship. Similarly, as nodes move relatively to each other, past loss rates may not reflect future communication capabilities. In wireless systems, nodes within the same small geographic region are often densely connected with other nodes in the same region. These nodes form a set of extended neighbor relationships that is referred to as a neighborhood. A neighborhood is typically composed of several nodes, with each node being densely connected to other nodes. These more dynamic neighbor relationships do not sit well with certain Internet Protocols designed assuming an fixed Ethernet like model to communication links (reflexive, transitive, and stable). Given the unknown neighbor relationships, the addressing model often associated with a Ethernet link is not valid. For example, in an Ethernet network routers are often told that a particular range of addresses are directly reachable. In MANETs' a node often cannot make assumptions that a particular set of addressable nodes is always reachable. Instead, nodes must detect and determine their neighbors, and handle the changes to their neighbors over time. 4.2.3. MANET Membership Given MANETs' characteristics (mobile, wireless, ad hoc), determining a MANETs' membership is difficult, if not impossible in certain scenarios. Chakeres, et al. Expires September 3, 2007 [Page 9] Internet-Draft MANET Architecture March 2007 /----------------------\ /----------------------\ | MANET | | MANET | | +---+ +---+ +---+ | | +---+ +---+ +---+ | | |MN1+-+MN2+-+MN3| | | |MN1+-+MN2+-+MN3| | | +-+-+ +---+ +---+ | | +---+ +---+ +-+-+ | | | | | | | | +-+-+ | Change | +-+-+ | | |MN4+ | in | |MN7| | | +---+\ | Time | +---+ | | \+---+ | \----------------------/ | +MN5+ | /----------------------\ | /+---+\ | | MANET | | +---+/ \+---+ | | +---+ +---+ +---+ | | |MN6+ +MN7| | | |MN6+--+MN4+--+MN5| | | +---+ +---+ | | +---+ +---+ +---+ | \----------------------/ \----------------------/ Figure 4: MANET(s) At one moment a MANET might consist of a certain set of nodes, and the next the MANET could partition into several MANETs. Later it might re-merge or merge with a new set of nodes and form a larger MANET. To assist in coordinating among a loosely connected set of MANET routers, a procedure called flooding is used. MANET flooding consist of disseminating a packet to all connected MANET routers. Certain routers in a MANET might connect to other routing regions. These routers are called MANET Border Routers (MBR), and they often run multiple routing protocol instances. The MBR are responsible for choosing the routing information to share between the various attached routing regions. The MBR should also present a consistent picture of the nodes reachable through them. As MANET membership changes, so does the connectivity of MBR within the MANET. Therefore, a MBR may be challenged to present a consistent set of reachable nodes. It may even choose not to share routing information about the MANET topology to other routing regions. 5. Addressing, aka the MANET Prefix Model This section presents an architectural model for MANETs which preserves the integrity of the IP architecture while allowing for the particularities of MANETs. Chakeres, et al. Expires September 3, 2007 [Page 10] Internet-Draft MANET Architecture March 2007 This architectural model considers MANET nodes as routers with hosts attached, as illustrated in Figure 5. These attached hosts may be "external" (i.e. attached to the router via other network interfaces) or "internal" - however the important observation to make is, that the links between these hosts and the router are classic IP links. This fact implies that, from the point of view of the hosts and the applications running on these hosts, connectivity is via a classic IP link. Hosts and their applications are not exposed to the specific characteristics of the MANET interfaces and are connected to the MANET via a router, which has one or more MANET interfaces. <~~~~~~+~~~~~~> MANET <~~~~~~+~~~~~~> | INTERFACE | ''''''''''|'''''''''' ''''''''''|'''''''''' ' +-|-+ MANET ' ' MANET +-|-+ ' ' | R | Node ' ' Node | R | ' ' +-+-+ ' ' +-+-+ ' ' : : ' ' : : ' ' : +---+ ' ' : +---+ ' ' : | H | ' ============ ' : | H | ' ' : +---+ ' = : = ' : +---+ ' '''''''''':'''''''''' =CLASSIC IP= ' : ' +......+......+ =INTERFACES= ' +......+......+ ' : : ============ ' : : ' +-+-+ +-+-+ '+-+-+ +-+-+' | H | * * * | H | '| H | * * * | H |' +---+ +---+ '+---+ +---+' ''''''''''''''''''''' Figure 5: MANET Addressing Model If the MANET router is delegated a prefix p::, this prefix can be assigned to the classic IP link(s), and hosts can be assigned addresses from within this prefix, and configured with this prefix as illustrated in Figure 6. Specifically, the MANET interface(s) of the router are *not* configured with this prefix. The configuration of MANET interfaces is detailed below. Chakeres, et al. Expires September 3, 2007 [Page 11] Internet-Draft MANET Architecture March 2007 MANET <~~~~~~+~~~~~~> INTERFACE | ASSIGNED ''''''''''|'''''''''' PREFIXES ' MANET +-|-+ ' ========= ' Node | R | ' <=== P:: = ' +-+-+ ' ========= ' : : ' ' : +---+ ' ========= ============ ' : | H | ' <=== P:1:: = = : = ' : +---+ ' ========= =CLASSIC IP= ' : ' =INTERFACES= ' +......+......+ ' ============ ' : : ' '+-+-+ +-+-+' ========= '| H | * * * | H |' <=== P:2:: = '+---+ +---+' ========= 'P:2::1 P:2::N' ''''''''''''''''''''' Figure 6: MANET Node and Prefixes MANET specific behaviors are exclusively exposed to the MANET interface(s) of the routers. This includes MANET routing protocols and interface and link characteristics (asymmetric neighborhoods, semi-broadcast interfaces, fuzzy neighbor relationships, topology dynamics, etc.). The following characteristics deserve particular mention, since they distinguish MANET interfaces and the MANET link model from the classic IP link model: Unique Prefixes MANET interfaces must be configured with unique prefixes, that is so that no two MANET interfaces are configured to appear within the same IP prefix. Some common ways to achieve this are: * unnumbered interfaces (IPv4) [RFC1812]; * link-local addresses (IPv6); * /128 (IPv6) or /32 (IPv4) prefixes. However it is worth noting that prefix lengths shorter than /128 (IPv6) or /32 (IPv4) are possible on the MANET interfaces, as long as the prefixes are unique to a single MANET interface. Chakeres, et al. Expires September 3, 2007 [Page 12] Internet-Draft MANET Architecture March 2007 Link-local Multicast/Broadcast Scope On a MANET interface, a link-local multicast or broadcast reaches MANET interfaces of neighboring nodes, regardless of their configured addresses. A link-local multicast or broadcast on a MANET interfaces is a "neighborcast" and is not forwarded, nor is it assumed to be received by all nodes within a MANET. The MANET addressing model presented in this section makes a clear separation between the role of router and host in a MANET, recognizing that: o MANET interfaces are seen only by the router, assumed to be MANET aware, and running appropriate protocols; o MANET interfaces forming a multihop MANET area may use a site prefix; o hosts and subnets on a non-MANET interface assume a classic IP link model; o applications on hosts and protocols assuming classic IP interfaces run unmodified. MANET protocols are developed to work on MANET interfaces. The MANET WG is chartered to develop routing protocols for MANET interfaces. The Autoconf WG is chartered to develop autoconfiguration protocols for MANET interfaces and MANET routers. 6. MANETs' Place in the Network Stack While the MANET WG is focused upon network (L3) routing, that does not imply that MANETs and their protocols are limited to L3. Several previous and existing efforts are applying MANET protocols at various layers. The challenges discussed above, exist independent of at which layer MANET protocols are deployed. Of course, the protocols themselves may need to be retooled slightly to accommodate the information available to the deployed layer. MANET MAC layer (L2) routing, more often called bridging, may work in homogeneous wireless networks for delivering frames over multiple hops. One example of L2 MANET is being developed in the IEEE 802.11s effort. L2 routing/bridging hides the multiple L2 hops from L3. This behavior can be advantageous as this network can transparently mimic an Ethernet, to some extent. The ability to mimic Ethernet allows the L2 MANET to utilize existing L3 network protocols. Chakeres, et al. Expires September 3, 2007 [Page 13] Internet-Draft MANET Architecture March 2007 Alternatively, this transparency may lead to performance problems. For example, if the L3 protocols make heavy use of broadcast messaging or devices assume that high-speed wired bandwidth resources are available. L2 MANET does not enable heterogeneity. That is, L2 MANET is not capable of bridging across heterogeneous interfaces. For example, L2 bridging cannot directly bridge two L2 technologies with different addressing schemes. It can also be difficult if the frame sizes of two L2 vary, as this could require breaking a single frame into multiple frames of a different format. L3 MANET enables heterogeneous networking, as IP was built with this feature in mind. Forming a MANET at L3 implies that the L3 protocols must handle the challenges presented in this document. MANET like protocols can also be used at higher layers. One example is peer-to-peer (P2P) networks. These networks have some of the same challenges as MANET, e.g. variable neighbor relationships and changing membership. 7. Cross Layering In wireless networks, and especially in MANET, extended interfacing among the network layers (physical, MAC, link, network, etc.) can be extremely useful. Arguably, for MANET deployments to be successful, some degree of cross layering should be considered. For example, link layer feedback that a packet/frame was not able to be sent or that it was not received could be used by the network layer to indicate that a neighbor is no longer reachable. This information and other extended interfacing could reduce, or eliminate, some upper layer messaging. Further, it could significantly reduce the latency in decision making. Note that though a certain lower layer information is valuable, it likely needs to be extrapolated or filtered before accurate assumptions about the network state can be made. For example, failure to deliver a frame by itself may not be a good indicator that a node is or is not reachable. In networks with several different layers of MANET mechanism, the sharing of information across different layers can be even more vital to creating and maintaining the network. For example, if a P2P network is run on top of a L3 MANET, the two networks can share information to use a similar optimized topology. Similarly, they could share neighbor state changes to reduce the messaging or latency in making decisions. Chakeres, et al. Expires September 3, 2007 [Page 14] Internet-Draft MANET Architecture March 2007 8. Deployment Taxonomy The present and future proliferation of inexpensive wireless interfaces continues to stimulate technical interest and developments in the area of MANET for a wide variety of deployment scenarios. In this section, we present several characteristics for describing expected MANET deployments. 8.1. Service Availability Nodes often expect certain services/servers to be available. When describing a deployment scenario, it is important to specify the expected services available and the distance between the participating devices. In MANET, nodes might assume a service is available locally (within one IP hop) or within a particular scope (one or more IP hops - MANET, site, global). Nodes might assume in certain deployments that no special servers/services are available. Finally, nodes might assume that servers are sometimes available, but their availability is not guaranteed or ensured. Different frameworks for autoconfiguration, network management, and intra-AS routing can be developed based upon the expected constraints and operating conditions. 8.2. Number of Peer MANET Routers The number of peer MRs in a MANET is an important consideration. This number is not the complete number of nodes in a MANET (since MRs may support an arbitrary number of connected nodes) but a measure of the number of MR participating as a cohesive flat routing area. That is, the number of MR within a single routing region. While the number of peer MRs does not define scalability of a MANET protocol, it is often useful to discuss the number of peer MR to get a feel for maturity of typical deployment solutions. For simplicity we define the following network sizes to aid in discussion: Small 2-30 MR peers Moderate 30-100 MR peers Large 100-1000 MR peers Chakeres, et al. Expires September 3, 2007 [Page 15] Internet-Draft MANET Architecture March 2007 Very large Larger than 1000 MR peers At the time of writing, small and moderate size peer MANET routing scenarios have matured and have reasonable testing and deployment experience. These sizes can perform reasonably well in many cases without hierarchy. MANET architectures can, of course, support routing hierarchies to improve scaling. Large and very large MANET routing areas that are flat are still a topic of active research and are not considered here. One can apply hierarchy to achieve scaling, but again that is not being discussed here. Existing MANET routing developments, such as SMF [I-D.ietf-manet-smf], have shown significant performance improvements and capabilities even in small peer router size deployments and experiments using classical routing designs. 8.3. Example Deployments Here we provide a short list of example deployment scenarios: Home, office, campus, and community mesh networks Disaster relief and first responder networks Sensor networks Range extension Military communications Automotive networks 9. Security Considerations TBD 10. IANA Considerations This is an informational document. IANA requirements for MANET related protocols will be developed within the protocol specifications for MANET protocols. 11. Acknowledgments Discussions and developments concepts and architectural issues have Chakeres, et al. Expires September 3, 2007 [Page 16] Internet-Draft MANET Architecture March 2007 evolved over many years of discussion of related work within the MANET WG. There are obviously many people that have contributed to past discussions and related draft documents within the WG that have influenced the development of these concepts that deserve acknowledgment. The authors would like to thank all contributors to the MANET and AUTOCONF WG efforts and those that have helped in the review and content process. While not entirely complete the authors would like to in particular thank the following individuals for there discussions and contributions: Jari Akko Emmanuel Baccelli Justin Dean Christopher Dearlove Tom Henderson Bob Hinden Thomas Narten Charles Perkins Subhranshu Singh Fred Templin Dave Thaler Seung Yi 12. Informative References [DWN03] Macker, J. and S. Corson, "Mobile Ad hoc Networking: Routing Technology for Dynamic, Wireless Networks", IEEE Press, Mobile Ad hoc Networking, Chapter 9, 2003. [FL01] Freebersyser, J. and B. Leiner, "A DoD perspective on mobile ad hoc networks", Addison Wesley C. E. Perkin, Ed., 2001, pp. 29--51, July 2001. [I-D.iab-multilink-subnet-issues] Chakeres, et al. Expires September 3, 2007 [Page 17] Internet-Draft MANET Architecture March 2007 Thaler, D., "Multilink Subnet Issues", draft-iab-multilink-subnet-issues-03 (work in progress), January 2007. [I-D.ietf-ipv6-2461bis] Narten, T., "Neighbor Discovery for IP version 6 (IPv6)", draft-ietf-ipv6-2461bis-10 (work in progress), January 2007. [I-D.ietf-manet-smf] Macker, J., "Simplified Multicast Forwarding for MANET", draft-ietf-manet-smf-03 (work in progress), October 2006. [I-D.templin-autoconf-dhcp] Templin, F., "MANET Autoconfiguration", draft-templin-autoconf-dhcp-06 (work in progress), February 2007. [RFC1812] Baker, F., "Requirements for IP Version 4 Routers", RFC 1812, June 1995. [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998. [RFC2453] Malkin, G., "RIP Version 2", STD 56, RFC 2453, November 1998. [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", RFC 2460, December 1998. [RFC2461] Narten, T., Nordmark, E., and W. Simpson, "Neighbor Discovery for IP Version 6 (IPv6)", RFC 2461, December 1998. [RFC2501] Corson, M. and J. Macker, "Mobile Ad hoc Networking (MANET): Routing Protocol Performance Issues and Evaluation Considerations", RFC 2501, January 1999. [RFC3513] Hinden, R. and S. Deering, "Internet Protocol Version 6 (IPv6) Addressing Architecture", RFC 3513, April 2003. [RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology", RFC 3753, June 2004. Chakeres, et al. Expires September 3, 2007 [Page 18] Internet-Draft MANET Architecture March 2007 Authors' Addresses Ian Chakeres Boeing The Boeing Company P.O. Box 3707 Mailcode 7L-49 Seattle, WA 98124-2207 USA Email: ian.chakeres@gmail.com Joe Macker Naval Research Laboratory Washington, DC 20375 USA Email: macker@itd.nrl.navy.mil Thomas Heide Clausen LIX, Ecole Polytechnique 91128 Palaiseau CEDEX France Email: T.Clausen@computer.org URI: http://www.lix.polytechnique.fr/Labo/Thomas.Clausen/ Chakeres, et al. Expires September 3, 2007 [Page 19] Internet-Draft MANET Architecture March 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). 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. 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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. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Chakeres, et al. Expires September 3, 2007 [Page 20]