AN Lesson-13

 Configuring LAN Routing-II

 

Routing table

Routing table is an electronic document that stores the routes to the various nodes in a computer network.

Routers read the destination addresses of received packets and then route those packets according to directions provided by routing tables.

Types of routes

■ Host route This type of route provides a route to a specific destination host or to a broadcast address. In IP routing tables, host routes are distinguished by a 255.255.255.255 network mask.

■ Network route This type of route provides a route to a specific destination network.In IP routing tables, network routes can be distinguished by any subnet mask between 0.0.0.0 and 255.255.255.255.

■ Default route Routing tables contain a single default route. This route is used to forward all packets whose destination address does not match any address listed in the routing table. In IP routing tables, the default route is defined by the 0.0.0.0 address and 0.0.0.0 network mask.

Static routing concepts

Routing:   static

                Dynamic

Static:               Procedures are manual in nature

Dynamic:          Procedures are automatic in nature

Static Routing	Dynamic Routing
A feature of IP.	A feature of routing protocols such as RIP or OSPF.
Routers do not share routing information automatically.	Routers share routing information automatically.
Routing tables are built and        sustained manually.	Routing tables are built and sustained dynamically.

Advantages of Static Routing

• Static routing is advantageous in small networks for which configuring a few static routes is simpler than configuring a dynamic routing protocol.
• Static routes are less resource-intensive than are dynamic routing protocols for low-bandwidth WAN links.

 Disadvantages of Static Routing

• The main disadvantage of static routing is that it is a feasible means of maintaining only small routed networks. As a network grows, the administrative cost of maintaining static routes quickly outweighs the cost of implementing and maintaining a dynamic routing protocol.
• A second disadvantage of static routing is the lack of fault tolerance. If a route is improperly configured, connectivity is disrupted until the problem is diagnosed and fixed.

 

Q.What is routing table? How man types of routes are found in a routing table? Give brief description of these routes?

Q.What do you mean by static routing? What are the advantages and disadvantages of static routing?