CHAPTER 3
Routing Protocols
The nodes in Ad hoc network are free to move in random fashion within the network region due to which the network topology changes randomly or dynamically. This random movement of nodes plays an important role on the performance of routing protocols[30,31]. Considering the node mobility feature it is essential to choose a suitable routing protocol based on the network environment. Because the nodes are mobile in nature and are moving randomly anywhere so its an important issue, to get a valid route between a source and destination node of the network[20,21,22].
A routing protocol is the set of rules which specifies that how routers communicate with each other, it also provide the information that enables them to select routes between any two nodes on a computer network. A routing protocol shares this information first among immediate neighbours, and then throughout the network. This way, routers gain knowledge of the topology of the network[24,25]. The term routing protocol may refer specifically to one operating at layer three of the OSI model, which shares topology information between routers. Although there are many types of routing protocols, three major classes are use on IP networks:
• Interior gateway routing via link state routing protocols
• Interior gateway routing via path vector or distance vector protocols
• Exterior gateway routing is the routing protocol used by the public Internet.
The specific characteristics of routing protocols include
• the manner in which they either prevent routing loops
• the manner in which they select preferred routes
• the time they take to converge
3. Classification of Routing Protocols
The routing protocols in MANETs can be classified into three categor...
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...ce no
2 2 1 16
3 2 2 32
4 4 1 38
5 5 1 45
7 4 2 98
8 2 3 111
9 2 3 118
10 4 3 186
11 5 3 189
12 5 4 192
Table 3.2
Routing table entries for node 1 after topology change
Destination Next node Distance Sequence no
2 2 1 16
3 2 2 32
4 4 1 38
5 5 1 45
6 5 2 89
7 4 2 98
8 2 3 111
9 2 4 146
10 4 3 186
11 5 3 189
12 5 4 192
When a Mobile Host receives new routing information (usually in an incremental packet as just described), that information is compared to the information already available from previous routing information packets. Any route with a more recent sequence number is used. The metrics for routes chosen from the newly received broadcast information are each incremented by one hop. Newly recorded routes are scheduled for immediate advertisement to the current Mobile Host’s neighbours [5,40,41,42].
The routing protocols for UWSNs can be categorized into two classes according to the preconditions they assume:
When using routers, you need many routers in order to route the information to the correct location, as one router will not be able to manage this task. Explain how the routing schemes handle this problem.
IP – The Internet Protocol (IP) - is the method or protocol by which data is sent from one computer to another on the Internet. Each computer (known as a host) on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet.
Johnson, D., Maltz, D. (1996). Dynamic Source Routing in Ad-hoc Wireless network. Print ISBN: 0 79239697 0
8) Ian F. Akyildiz, Ismail H. Kasimoglu, “Ad Hoc Networks’’, Wireless sensor and actor networks: Research Challenges, Georgia Institute of Technology, USA, May-2004.
Open Shortest Path First (OSPF) is a link-state routing protocol which uses link state routing algorithm for Internet Protocol (IP) networks.Using OSPF, th convergence of a network can be done in very few seconds, loop-free paths can be guaranteed and better load-sharing on external links can be achievd. Every change in the topology of the network is identified within seconds using OSPF and it instantaneously computes the “shortest path tree” for every route using “Dijkstra's algorithm” . For that reason, OSPF requires a router which have a more powerful processor and more memory than any other routing protocols which leads to more elect...
Each packet of information that is sent is identified by the IP address which reveals the source of the information.
Perhaps the most redundant, fault-tolerant of all network topologies is the mesh LAN. Each node is connected to every other node for a true point-to-point connection between every device on the network.
The Internet is, quite literally, a network of networks. It is comprised of ten thousands of interconnected networks spanning the globe. The computers that form the Internet range from huge mainframes in research establishments to modest PCs in people's homes and offices. Despite the recent hype, the Internet is not a new phenomenon. Its roots lie in a collection of computers that were linked together in the 1970s to form the US Department of Defense's communications systems. Fearing the consequences of nuclear attack, there was no central computer holding vast amounts of data, rather the information was dispersed across thousands of machines. A set of rules, of protocols, known as TCP/IP was developed to allow disparate devices to work together. The original network has long since been upgraded and expanded and TCP/IP is now a "de facto" standard.
We consider a wireless sensor network with N = 100 nodes distributed randomly in 100m X 100m field. A gateway node is deployed in the centre of the sensing field. The BS is located far away from the sensing field. Both gateway node and BS are stationary after deployment. We consider packet size of 4000 bits. We compare our protocol with LEACH protocol. To assess performance of our protocol with LEACH, we ignore the effects caused by signal collision and interference in the wireless channel. Table 1 shows the radio parameters used in our
3G technology is considered the “third generation” in mobile technology and has provided services to cell phone users for over 10 years. 3G ushered in the smartphone era enabling users to check e-mail, text, call and take advantage of streaming data on their devices. “The transfer rate for 3G networks is between 128 and 144 kbps (kilobits per second) for devices that are moving fast and 384 kbps for slow ones (like for pedestrians). For fixed wireless LANs, the speed goes beyond 2 Mbps.” 1
Signalling theory was proposed by Michael Spence which says that people are selected by their innate abilities and the educational levels they have attained as the theory says that abilities shown by educational levels signal that a particular man/women has good abilities and is eligible and so the consequence of this is that the more the educated the more the salary he/she gets.
The first network ARPANET was a network with several computers that performed packet switching that was used to connect to each other by modems (Edwards and Bramante, 2009. p.29). Technological advances, network evolution, and type of communications have changed, but the basic building blocks of a network remain the same. A device to communicate from, a medium of communication, and a device to communicate with. The communication devices are no longer just a big and bulky computer in a University laboratory, they vary from personal computers, smartphones, ATM machines, to supercomputers, and any numerous other devices and new inventions introduced on regular basis. Regardless of the type, these communication devices require a way to enter a network, which are network interface cards, networks hubs, and modems. These are the devices that convert the data into a signal that can be transported over the network from one communication device to another (Edwards and Bramante, 2009). The medium of transmitting the signal can be wired or wireless. A wire communication depends on copper or fiber optic wires and the wireless communications using radio signals. The internet is comprised of numerous networks that control many aspects of everyday life spanning from the energy services to utilities, to telecommunications, transportation, finance, research,
TCP/IP is a network model which enables the communication across the Internet. The most fundamental protocol on which the Internet is built. This is made up of the 2 common networking protocols, TCP, for Transmission Control Protocol, and IP, for Internet Protocol. TCP maintains and handles packet flow linking the systems and IP protocol has the ability to handle the routing of packets. However The TCP/IP stack consists of 5 layers first being application layer, the transport layer, then the network layer, the link layer and finally the physical layer. The assignment focuses on the three middle layers and is divided into five parts. Firstly explaining how the TCP and UDP the most vital protocols needed to deliver and communicate.
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