Ad-Hoc Networking TIA Prime PSO with ETSI inputs

1. GSC9/GRSC_026 Ad-Hoc NetworkingTIA Prime PSO with ETSI inputs GSC-9, Seoul 1

2. Overview of Ad Hoc Networks

3. Initial Architectures - Low power sensors networks “surveillance” web - small, relatively static, embedded ad hoc networks `“bluetooth-type” networks - Small-to-medium sized, mobile ad hoc networks “802.11-style” GSC-9, Seoul

4. Terminlology Mobile Ad Hoc Networking = = Mobile, Multi-hop, Wireless Networking = Mobile Mesh Networking = Mobile Packet Networking GSC-9, Seoul

5. Hybrid Communication Networks Satellite overlay High-speed backbone network MANET No fixed infrastructure Fixed/static infrastructure GSC-9, Seoul

6. Properties of Ad Hoc Networks • Allows devices to establish communication, anytime and anywhere without the aid of a central infrastructure. • Autonomous, self-organizing terminals • Unknown number of terminals, may vary • Topology unknown in advance, may vary • Distributed routing • Every terminal is a router • Information needed for routing is learned adaptively • Distributed network control • Admission, security • Flow control • Quality of service Mobile Ad Hoc Networks (MANETs) Fixed Ad Hoc Networks (e.g., “Mesh”) MOBILITY GSC-9, Seoul

7. Mesh Networks • Fixed or low-mobility wireless ad hoc networks • Emphasis on self-configuration in a variety of situations, including failure of components • Emphasis on adaptive, distributed network management IEEE 802.11 ESS Mesh Example: Proposed extension to IEEE 802.11 to specify means for a wireless ad hoc formation of a backbone network of access points (APs) to form an ESS 802.11 ESS (Extended service set) 802.11 BSS (Basic service set) GSC-9, Seoul

8. High mobility Communication over wireless radio links Emphasis on rapid deployment of autonomous mobile users Decentralized structure Dynamic topology Stand-alone or connected to larger network via gateway Nodes in network can serve as routers and hosts Can forward packets on behalf of other nodes and run user apps. Contends with effects of radio communication interference or congestion Applicable to PPDR, military, commercial enterprise, etc. i.e., MANETs Mobile Ad Hoc Networks GSC-9, Seoul

9. Sensors spread across a geographical area Large number of (mostly stationary) sensors Low energy use Network self-organization Collaborative signal processing Querying ability Each sensor has wireless communication capability and sufficient intelligence for signal processing and networking of the data Node classifications: Individually addressable, and whether the data in the network is aggregated Military, environmental, traffic, surveillance Can assist in the national efforts to increase alertness to potential terrorist threats. Smart Sensor Ad Hoc Networks GSC-9, Seoul

10. Network Architecture of Wireless Ad Hoc Networks • Peer-to-peer: flat architecture, though may organize into “clusters” for network management purposes • Adaptable to varying topology and traffic conditions • Robust: Degrades gracefully in face of node / link failures and local congestion • Efficient (bandwidth, power consumption, user capacity) through multihop communications & spatial reuse • Possibility of QoS provision • Scalable GSC-9, Seoul

11. Mobile Ad Hoc Networking (MANET) • Dynamic topologies • Bandwidth-constrained • Asymmetric links with variable capacity • Energy constrained • Multiple technologies can be used simultaneously GSC-9, Seoul

12. MANET Routing Algorithm Criteria • Dynamic routing algorithms: Must adapt to • Entering/departing nodes • Changes in link quality and terrain • Traffic patterns and interference • Rate of topological change • Fast run time compared to rate of topology change • Low overhead and storage requirements • High throughput and low packet delay time • Preserve network requirements (e.g., security) • Efficient use of power GSC-9, Seoul

13. MANET Routing Protocols(Present or past IETF drafts, some inactive) • Dynamic Source Routing (DSR) • Ad Hoc On-Demand Distance Vector (AODV) • Optimized Link State Routing (OLSR) • Topology Broadcast based on Reverse-Path Forwarding (TBRPF) • Zone Routing Protocol (ZRP) • Temporally-Ordered Routing Algorithm (TORA) • Landmark Routing Protocol (LANMAR) for Large Scale Ad Hoc Networks • Fisheye State Routing Protocol (FSR) for Ad Hoc Networks GSC-9, Seoul

14. IETF MANET standardization • MANET - established in 1997 chartered working group within Internet Engineering Task Force (IETF) • Focussed on studying routing specification with the goal of supporting network scaling up to hundreds of routers * Unicast routing protocol * Multicast routing protocol • Work on routing for large and small scale networks • Work relies on the existing IETF standards such as mobile-IP and IP addressing • For large-scale MANET the lack of interest has put this work in question • Flooding: work on requirements had started GSC-9, Seoul

15. Comment on IETF MANET work • Early approval constraints due to the accumulation of variant ad hoc routing protocols and the need to identify a “killer application.” • Research now assigned to IRTF (research component of IETF), and the IETF group is working toward implementable unicast and multicast protocols in the near term. GSC-9, Seoul

16. Ad Hoc Routing Protocol Example 1: the DSR Protocol • Data packets have source routesstored in their headers. Each node on the path transmits the packet to the next hop identified in the source route. • Each node maintains a Route Cachetostore the source routes it has learned. When a node needs to send a data packet, it first checks its route cache for a route to the destination. If no route is found, it attempts to find one using the route discovery mechanism. • A monitoring mechanism, called route maintenance, is used in each operation along a route. This mechanism checks the validity of each route used. GSC-9, Seoul

17. Ad Hoc Routing Protocol Example 2: the AODV Routing Protocol • Each node maintains a table of hop distances and next-nodes for different destinations. • Routes are built on demand using a route request (RREQ)/ route reply (RREP) query cycle. • Once the source stops sending data packets, the links will time out and eventually be deleted from the intermediate node routing tables. • If a link breaks while the route is active, the node upstream of the break propagates a route error (RERR) message to the source node to inform it of the now unreachable destination(s). GSC-9, Seoul

18. Example NIST/WCTG MANET Work Analysis: • Development of network performance measures, standard evaluation scenarios, analysis of multihop network properties and performance Simulation: • OPNET simulation/evaluation of multihop routing protocols, “cost-adaptive mechanisms” for choosing paths Embedded Implementation: • Development of Linux kernel implementation of AODV • Development and testing of communication and localization system prototype based on ad hoc networking URL: http://w3.antd.nist.gov/wctg/manet/ GSC-9, Seoul

19. NIST Distributed Testbed for First Responders • Hardware: • Compaq iPAQs running Linux, dual PCMCIA card backpack with battery, 802.11b cards, full-duplex audio. • Capabilities: • Multihop packetized voice: broadcast, multicast, unicast; group IDs, etc. Packets include terminal sensor data. • Indoor localization: 1 to 3 m using signal strengths; display of terminal locations. • External communication: Interface to external networks using Session Initiation Protocol. GSC-9, Seoul

20. Emerging Applications of Ad Hoc Networking • Mesh applications may be becoming popular alternatives to building new wired infrastructure • Commercial/personal ad hoc networking capabilities • Including Peer-to-peer • Emerging sensor networks • Ad hoc principles are proposed to enable multihop extensions of WLAN/RLAN structures • Complete solutions are needed before the special features of ad hoc networking may be considered advantageous • i.e., network management, distributed database, VoIP, capacity for multimedia, etc.—these solutions are emerging as different types of wireless systems converge • IEEE, ITU-R and other standards bodies have existing and initiated evolutions to existing standards that may be beneficial to ad hoc networking applications (including security, RLAN, etc.) • Other standards activity: • Project MESA (part of proposed PPDR capabilities) GSC-9, Seoul

21. Ad Hoc Network Applicability Scale Small scale Large scale Network type (few nodes) (many nodes) Commercial home/office personal mobile cellular like industrial local networks Government specific Public Safety Large-scale military network Community/urban “covert” networks local communications networks GSC-9, Seoul

22. Ad Hoc Networking • Lack of specific network layer standards for Ad Hoc networking. • Note the term "ad hoc" can also be used in a more general sense, applying to networking modes involving Bluetooth-like abilities and other WPANs as well as use of 802.11 as the radio protocol. • Need for GSC/GRSC Resolution? • Clarify and focus subject GSC-9, Seoul

23. Open issues • A optimisation network layer and radio layers for different systems (incl. 802.11, HiperLAN) • B QoS support • C secuirity • D mobility • B, C, D issues could be orthogonal, joint optimization is very difficult (system design choice) • tradeoff between centralized and distributed algorithms for B,C,D GSC-9, Seoul

24. Relevant ETSI activities • MESA Project - ad hoc network on future Public Safety communications • BRAN - HiperLAN-2, other • 3GPP - UTRA TDD Standardization challenges => There is need for standard-based approach at the network layer. GSC-9, Seoul

25. Ad Hoc Networking Thank You! GSC-9, Seoul