Small State and Small Stretch Routing Protocol for Large Wireless Sensor Networks

  1.ABSTRACT :

                       

                             Routing protocols for wireless sensor networks must address

the challenges of reliable packet delivery at increasingly large scales and with highly constrained node resources. Attempts to reduce routing state can result in undesirable worst-case routing performance, as measured by stretch, which is the ratio of the hop count of the selected path to that of the optimal path. We present a new routing protocol, Small State and Small Stretch (S4),which jointly minimizes the state and stretch. S4 uses a combination of beacon distance-vector based global routing state and scoped distance-vector based local routing state to achieve a worst-case stretch of 3 using O(√N) routing state per node in an N-node network. Its average routing stretch is close to 1. S4 further incorporates local failure recovery to achieve resilience to dynamic topology changes. We use multiple simulation environments to assess performance claims at scale, and use experiments in a 42-node wireless sensor network testbed to evaluate performance under realistic RF and failure dynamics. The results show that S4 achieves scalability, efficiency, and resilience in a wide range of scenarios.

 

  2. EXISTING SYSTEM :

                                        Routing finds paths in a network along which to send data. It is one of the basic network functionality. The effectiveness of routing protocols directly affects network scalability, efficiency, and reliability. With continuing growth of wireless network sizes, it is increasingly important to develop routing protocols that simultaneously achieve :

i)     Small routing state: Using small amounts of routing state is essential to

                                achieving network scalability. Many wireless   devices   

                                are resource constrained.

ii)    Small routing stretch: Routing stretch is defined as the ratio between the

                                   cost of selected route and the cost of optimal route. 

                                  Small routing stretch means that the selected route  

                                  is efficient compared to the optimal route. It is a key

                                  quantitative measure of route quality, and affects

                                           global resource consumption, delay, and reliability.

     Iii) Resilience:                Wireless networks often experience frequent 

                                           topology changes arising from battery outage, node

                                           failures, and environmental changes. Routing           

                                           protocols should find efficient routes even in the            

                                           presence of such changes.

 Existing routing protocols either achieve small worst-case routing stretches with large routing state (e.g., shortest path routing) or achieve small routing state at the cost of large worst-case routing stretches (e.g., geographic routing and hierarchical routing).

  3. PROPOSED SYSTEM :

                                           We present S4 as a scalable routing protocol in large wireless networks to simultaneously minimize routing state and routing stretch in both normal conditions and under node or link failures. S4 incorporates a scoped distance vector protocol (SDV) for intra-cluster routing, a resilient beacon distance vector protocol (RBDV) for inter-cluster routing, and

distance-guided local failure recovery (DLF) for achieving resilience under failures and topology changes.S4 uses the theoretical ideas of the compact routing algorithm  as a basis, refined by the addition of new techniques needed to obtain a practical routing protocol for large-scale wireless networks.

                            To achieve S4  desirable balance among these characteristics, which is well suited to the wireless sensor network setting the

following contributions were made:

          1)S4 is the first routing protocol that achieves a worst case routing stretch  

             of 3 in large wireless networks. Its average routing stretch is close to 1.

          2)S4’s distance guided local failure recovery scheme significantly

              enhances network resilience, and is portable to other settings.

3)   S4’s scalability, effectiveness of resource use, and resilience are

validated using multiple simulation environments and a 42-node sensor network testbed.

  4.HARDWARE REQUIREMENTS:

•         System                : Pentium IV 2.4 GHz.

•         Hard Disk            : 40 GB.

•         Floppy Drive       : 1.44 MB.

•         Monitor                : 15 VGA Colour.

•         Mouse                 : Logitech.

•         Ram                     : 256 MB.

   5.SOFTWARE REQUIREMENTS:

•         Operating System       : - Windows XP Professional.

•         Front End                               : - Asp .Net 2.0.

•         Coding Language       : - Visual C# .Net.