IP ROUTING -1 STATIC ROUTING DEFAULT ROUTING

 A routing protocol is used by routers to dynamically find all the networks in the internetwork and to ensure that all routers have the same routing table.  Basically, a routing protocol determines the path of a packet through an internetwork.  Examples of routing protocols are: RIP, RIPv2, EIGRP, and OSPF. 2 Routing protocol and Routed protocol

 Once all routers know about all networks  a routed protocol can be used to send user data (packets) through the established enterprise.  Routed protocols are assigned to an interface and determine the method of packet delivery.  Examples of routed protocols are: IP and IPv6.

Routing basis  The term routing is used for taking a packet from one device and sending it through the network to another device on a different network. Routers don’t really care about hosts, they only care about networks and the best path to each network.  The router learns about remote networks from neighbor routers or from an administrator.

Routing basis  The router then builds a routing table that describes how to find the remote networks.  If a network is directly connected, then the router already knows how to get to it.  If a network isn’t directly connected to the router, the router must use one of two ways to learn how to get to the remote network: static routing, meaning that someone must hand-type all network locations into the routing table, or something called dynamic routing.

Dynamic routing  a protocol on one router communicates with the same protocol running on neighbor routers. The routers then update each other about all the networks they know about and place this information into the routing table. If a change occurs in the network, the dynamic routing protocols automatically inform all routers about the event.

Static routing  The administrator is responsible for updating all changes by hand into all routers.  Typically, in a large network, a combination of both dynamic and static routing is used.

Static routing benefits:  There is no overhead on the router CPU, which means you could possibly buy a cheaper router than you would use if you were using dynamic routing.  There is no bandwidth usage between routers, which means you could possibly save money on WAN links.  It adds security because the administrator can choose to allow routing access to certain networks only.

Static routing disadvantages:  The administrator must really understand the internetwork and how each router is connected in order to configure routes correctly.  If a network is added to the internetwork, the administrator has to add a route to it on all routers by hand.  It’s not feasible in large networks because maintaining it would be a full-time job in itself.

Instructions

 Router(config)# ip route [destination_network] [mask] [next- hop_address or exitinterface] [administrative_distance] [permanent]  used to add static route records to the routing table for example:  Router(config) #ip route  The ip route command tells us simply that it is a static route.  is the remote network we want to send packets to.  is the mask of the remote network.  is the next hop, or router, we will send packets to

Default route  We use default routing to send packets with a remote destination network not in the routing table to the next-hop router.  You should only use default routing on stub networks, those with only one exit path out of the network.  router(config)#ip route

Using packet tracer in router addressing 1- We connet the figure.  The cables used are : · Straight : between switch, pc and router, switch. · Cross : between switch, switch. · Serial : betweeen the two routers.

Using packet tracer in addressing 2- We put the IP address for each device as the following :  We have in the figure 3 networks :

Using packet tracer in addressing  To distribute the Ip's on the router interfaces we do the following :  Router 0:

Using packet tracer in addressing  For the second router (Router1 ) :

Using packet tracer in addressing  Give each PC it’s IP address, Subnet Mask and Default Gateway:  For PC0 : From IP configuration :

Using packet tracer in addressing  How to ping from PC0 to the default gateway :  For PC0 :

Using packet tracer in addressing We chose command promot and ping on the default gateway :

Routing using packet tracer  To let serial work we must give clock to DCE terminals :  We use (show controllers serial Name ) in privilage mode to examine the serial terminal then we put the clock using the command ( clock rate rate ) in global configuration mode.  We begin with router0 :  It’s DTE  So we don’t make any thing

Routing using packet tracer  For router 1 : It’s DCE  So we write:

Static Route  For Router 0:  The routing table :

Static Route We give static route for Router 0 :

Static Route For Router 1: The routing table :

Static Route We give static route for Router 1 :

Static Route  Now we ping from PC to any other PCs to make sure they see each other :  From PC0 to PC3 & PC6

Practical part 2  We connect the following network :

Routing using packet tracer  For each PC we put the Ip address, gate way and subnet mask.  For PC0 :

Routing using packet tracer  Now we distribute the IP's on routers' interfaces :  For router0 :

Routing using packet tracer  For router1 :

Routing using packet tracer  For router2 :

Routing using packet tracer  To let serial work we must give clock to DCE terminals :  We use (show controllers serial Name ) in privilage mode to examine the serial terminal then we put the clock using the command ( clock rate rate ) in global configuration mode.  We begin with router0 :

Routing using packet tracer  We notice that the two terminals are DCE.

Routing using packet tracer  We give it clock since it's DCE :

Routing using packet tracer  for router1 :

Routing using packet tracer  for router2 :

Routing using packet tracer  Now we must do static routing to let the PC's of each network see the PCs in the remote network :  We begin with router0 :  There are two remote networks which have the Ips : , and three neighbors networks we know them by ( show ip route ):

Routing using packet tracer

For router 1 :

Routing using packet tracer

For router 2 :

Routing using packet tracer  Now we ping from PC to any other PCs to make sure they see each other :  Ping from PC 1 to PC0 & PC2:

DHCP router  To let the router distribute the IPs on the network we do the following :  Router 0 :

DHCP  We notice that the PC1 took a dynamic IP :