Link state routing algorithm in computer network

-

     Link state routing algorithm

Link State Routing –
Link state routing is the second family of routing protocols. While distance vector routers use a distributed algorithm to compute their routing tables, link-state routing uses link-state routers to exchange messages that allow each router to learn the entire network topology. Based on this learned topology, each router is then able to compute its routing table by using a shortest path computation.
Features of link state routing protocols –

  • Link state packet – A small packet that contains routing information.
  • Link state database – A collection information gathered from link state packet.
  • Shortest path first algorithm (Dijkstra algorithm) – A calculation performed on the database results into shortest path
  • Routing table – A list of known paths and interfaces.
Calculation of shortest path –
To find shortest path, each node need to run the famous Dijkstra algorithm. This famous algorithm uses the following steps:
  • Step-1: The node is taken and chosen as a root node of the tree, this creates the tree with a single node, and now set the total cost of each node to some value based on the information in Link State Database
  • Step-2: Now the node selects one node, among all the nodes not in the tree like structure, which is nearest to the root, and adds this to the tree.The shape of the tree gets changed .
  • Step-3: After this node is added to the tree, the cost of all the nodes not in the tree needs to be updated because the paths may have been changed.
  • Step-4: The node repeats the Step 2. and Step 3. until all the nodes are added in the tree
Link State protocols in comparison to Distance Vector protocols have:
  1. It requires large amount of memory.
  2. Shortest path computations require many CPU circles.
  3. If network use the little bandwidth ; it quickly reacts to topology changes
  4. All items in the database must be sent to neighbors to form link state packets.
  5. All neighbors must be trusted in the topology.
  6. Authentication mechanisms can be used to avoid undesired adjacency and problems.
  7. No split horizon techniques are possible in the link state routing.

Comments

Post a Comment

Popular posts from this blog

INTRODUCTION OF DBMS

-
What is Database :- The database is a collection of inter-related data which is used to retrieve, insert and delete the data efficiently. It is also used to organize the data in the form of a table, schema, views, and reports, etc. For example: The college Database organizes the data about the admin, staff, students and faculty etc. Using the database, you can easily retrieve, insert, and delete the information. DBMS (Database Management System):- Database management system is a software which is used to manage the database. For example: MySQL, Oracle, etc are a very popular commercial database which is used in different applications.DBMS provides an interface to perform various operations like database creation, storing data in it, updating data, creating a table in the database and a lot more.It provides protection and security to the database. In the case of multiple users, it also maintains data consistency. DBMS allows users the following tasks:- Data Definition: I
Read more

Introduction of Digital computer

-
Image
INTRODUCTION Digital computer concept:- 1. Digital computers are designed to store, process and communicate information in digital form. 2. Digital computer is any of a class of digital devices capable of solving problems by processing information in discrete form. 3. It is used for processing data represented by discrete, localized physica signals, as the presence or electic current. 4.The main three components of digital computer:- >input:- The user gives a set of input data through input devices. >Processing :- The input data is processed with the help of CPU by well defined and finite sequence of step. >Output : - Some data available from the processing step are output to the user. TYPE OF DIGITAL COMPUTER :- 1.Microcomputer/Desktop computer 2.Minicomputer 3.Mainframe computer 4.Supercomputers Microcomputer :- 1.Microcomputer is also called a personal computer or desktop computer. 2.It includes a microprocessor, memory, and
Read more

DEVELOPED, UNDEVELOPED AND DEVELOPING ECONOMIES || LIST, GDP, UNEMPLOYMENT

-
Image
There are 195 countries in the  world, some are developed countries, some are undeveloped , and some are underdeveloped or developing countries . The distinction between them is a different process but we can differentiate based on conditions like economic growth , GDP, employment rate , population, etc. Let's understand how we can say whether the country is developed. ADVANCE OR DEVELOPED ECONOMIES An advanced or developed economy is one, which carries on production with a large amount of machinery and advanced techniques. An advanced economy employs its human and other resources to the maximum extent possible.  The productive efficiency of a developed economy is of a very high order, and the per capita income is also high. Consequently, people in these countries enjoy high standards of living.  England, the U.S.A, France, west Germany, etc, are advanced economies. These economies are inhabited by over one-fourth of the entire population of the world. ADVANCED ECONOMY Advanced Ec
Read more