Configure Dynamic Routing OSPF.

What is OSPF?

OSPF Open Shortest Path Fast is a link state routing protocol developed based on Open Stranded. So it works with other routers, including Cisco. OSPF is used as the gateway protocol for the interior.

How does OSPF work?

OSPF sends LSA ads to all routers in one area. This LSA includes the value of the linked interface, the value of the metric, and the value of other variables and uses the SPF algorithm. This algorithm provides a path to startup and low cost. This SPF algorithm is known as the Dijkstra algorithm.

Features of OSPF:

⇰  OSPF divides the routing domain into an area.

⇰  Route updates only when the route is changed.

⇰  The only route that has changed is the information on the LSA (Link State Advertising).

⇰  Hello exchanges massages to build a neighbor.

⇰  Supports OSPF variable length subnet mask (VLSM) and classless inter domain routing (CIDR).

⇰  OSPF supports numerous network hops.

⇰  The multicast addresses of the OSPF are (224.0.0.5 and 224.0.0.6).

⇰  The algorithm used is Dijkstra's Shortest Path Fast.

OSPF Networking Hierarchy:

One of the interesting things of the OSPF is how it divides the network into several areas and hierarchies. As a result, it collects all the information from an area border router.

Area 1 is where the backbone routers are located. Area 3 is connected to the area border routers. Autonomous System border router is used to connect to any other routing domain.

Another interesting thing is the table:

OSPF uses 3 tables- neighbor table link-state table and routing table. The combination of these three tables gives the OSPF the entire network image.

Neighbors table:

This table contains information about which router is adjacent to a router.

Link state table:

This table contains information about the status of any of the links associated with neighboring routers.

Routing table:

The routing table will contain information about the cost of each link in the Link State table.

Basic concepts of EIGRP or Dynamic Routing.

Dynamic Routing:

Today we try to learn about dynamic routing EIGRP. It is good to remember that CCNA testing involves a simulation with EIGRP. So EIGRP is very important for CCNA testing.

Basic concepts of EIGRP:

EIGRP is an end-to-end gateway routing protocol. This is a protocol that actually features the link-state routing protocol and again it contains many features of the Distance Vector Routing Protocol. With this in mind, the EIGRP is called the Hybrid Routing Protocol. Now the question is what is the Distance Vector Routing Protocol and the link-state routing protocol? By means of the Distance Vector Routing Protocol, the router learns about the neighbor's router on the network and the location of all routers, ie the distance to which the routers are located. And through link routing, you can find out the troubles of each link and select the best.

The benefits of EIGRP are:

1. Supports CIDR and VLSM

2. The EIGRP places a backup path on the topology table so that any problem with the path communicates with the backup path.

3. Determines the value of each router using the DUAL (Diffusing Update Algorithm).

4. The default hop count is -100

5. Send hello messages to neighboring routers. The answer to that hello message is to know which router network is active. This results in faster convergence.

Let's see how the EIGRP works?

First, let's try to learn about EIGRP packets

1. Hello - This packet creates a relationship with the neighboring router.

2. Updates - Updates are used to send updates to the routing table.

3. Query - If there is a problem with the main route, the query sends a packet to know if there is a backup path.

4. Replay - If a neighbor router provides backup path, replay message provides.

5. Reconciliation - Receive the packet through the Reconciliation packet.

Static Routing.

Static Routing:

If there are a few routers too close to the network then static routing is better. As a result, the network will be less secure with less bandwidth.

The advantages of using a static route are:

Routing Efficiency: Static Routing a router works very fast. This results in lower cost of network bandwidth

Security: You can control the way your data flows by manually configuring some routes.

There are some disadvantages of using a static route:

Maintenance: If the route of the network is changed then it has to be changed manually. While this is possible for small networks, it can be difficult for large networks.

Precision: Manually configuring the route is more likely to go wrong.

The only way to follow a static route is to follow the syntax:

Ip route dest-network subnet (next-hop-ip interface)

Destination Network:

You need to specify the address of the destination network.

How to Work Switch, STP , RSTP OR VLAN.

SWITCHING:

The switch is a networking device, which is the second layer of the OSI model Works. Now the question is what is the second layer of the OSI model? We already knew that the traditional layer of the OSI model is the Data link layer. Data link is the frame which is the data format in Layer. That is to say, the origin of a frame switch is real, the switch sends the frame to the destination MAC address.

SWITCHING AND HISTORY:

Let's not know how the network worked when there was no switch. In 1980, coaxial cable was used. Whose data was capable of transfer up to 185 meters. The two connectors used to connect the T-connector came next to the hub, the problem that the hub faced was broadcast. That is, sending data to a port broadcasts to all ports. The bridge is designed to eliminate this problem. The only thing it did was convert several segments of the network into segments. As a result, the broadcast size gets smaller. The only limitation of this was that it started broadcasting between the networks within the segment. The switch comes after solving all such problems. The function that the switch performs is to transfer data to the port on which you transfer data. Other posts are free.

SWITCHES THAT DO THE WORK:

 ⇰   The switch collects the MAC addresses of the devices connected to the Mac table. As a result, a                                  Mac  request can actually be learned.

 ⇰   Decides whether the request from one host will actually forward to the port of another host.

 ⇰   Network switches there are network access monitoring systems.

Now let's try to know a little STP.

Now maybe a question may come to everyone that suddenly why STP? Need to know about STP because STP eliminates switching loop. 

Let's see how STP eliminates the switching loop. That is,

   ⇰   The STP first selects the route bridge.

   ⇰   Later, the type of port is determined.

   ⇰   Finally, convergence.

1. How does STP select the route bridge?

STP checks the bridge ID to select the route bridge. That is, the switch ID is less than the bridge ID of the switch port. The Bridge ID is the Bridge Charity and the MAC address, which is the lower the cost of the MAC address, the port will be the root bridge.

2. How to determine the type of pot next?

Determining the type of STP port means the cost of the route from the route bridge to the no root bridge. Different links have different types of costs. Select the link that will cost less.

Here is a link cost chart:

BANDWIDTH	STP EXPENSE
10 GBPS	2
1 GBPS	4
100 MBPS	19
10 MBPS	100

This is determined by the cost.

3. The latest is convergence.

This is how the middle loop of the switch is removed. The STP spends about 50 seconds completing this task. This time tomorrow is convergence time.

RSTP:

The convergence time of STP is higher than the RSTP protocol. The RSTP is the rapid spanning tree protocol. Convergence in this protocol takes only 50 seconds.

Network Router And Route.

What is a Network router and route?

The router is an integrated device that works on layer 3 and sends out a packet to another network. And Network is the only way to send packets to another network without having to send another packet.

Flash Memory:

Flash memory is used as a depository in the operating system.

RAM:

RAM is used to store information on the rooting table and submit files for running configuration.

Enviam:

Enviom is used as a backup file.

Typically there are three routing routes:

1. Static route  

2. Dynamic Route

3. Diff Route

Static route:  

Thick network may be affected by the routing route. Updating it if you want to change the route.

The comma of the static route is:

Ip route dest-ip subnet [next-hop-ip / interface]

Dynamic Route:

Dynamic Route is all routes that you can visit along the route. Failure is not to do anything. Any route is routed to the Hell Seat Automotive Routing Table.

Diff Route:

If you do not have the ability to determine which router to listen to, the router will use the default interface to select the same route.

Router Basic Security Setup.

Cisco is the mode configuration system.  

Typically 3 mod modes are available on Cisco router.

EXE mode:

The Cisco router group includes the EXE mode with the default operation mode. ISO kicks off after launching the Cisco device And Ace at EXE Mod. Exe mod will be ">" selected. The following is a description of the password entry in this EXE mode.

VLSM Subnet Mask.

VLSM

VLSM is a Variable Length Subnet Mask. VLSM allows us to use a network multiple subnet mask.

Why VLSM is required?

VLSM is needed to handle IPs properly, is to minimize IP abuse.Because many clients of a single client need an IP of one range. So through VLSM I can give clients IP as per their requirement. Looking at an example we can easily explain.

Suppose is a new company. They need a certain number of IPs for their different departments. Their IP request is:

The management team will need 100 IPs.

Sales team will need 50 IPs.

The account team will require 25 IPs.

The IT team will need 5 IPs.

And our network is - 192.168.1.0

Before doing the Practical, I have reviewed some information before. For exiting the host number = the bits that are off is 2 ^ (total number) -2

For excluding network numbers = bits that will be extra on 2 ^ (total number) of bits= 24-last writ value for subnet ID release. 

Step-1: For 100 host.

When doing VLSM, it is best to take the highest number of IPs first. The result is easy to calculate. For example, the maximum number of IPs required is 100. So for 100 host IP we have to take 2 ^ 7 = 128-2 = 126. Then the subnet mux will be – 255.255.255.128 and the network will be – 192.168.1.0/25.

Step-2: For 50 host.

The second highest number of IPs is 50. Which is what the sales team needs. So for 50 host IP's we have to take (2 ^ 6) = 64-2 = 62. So since 6 bit is used for the host then the rest of the bits is (32-6) = 26.Again since Class C since 24 is fixed, extra bits are needed (26-24) = 2. According to the above data the value of the second bit is - 192. So our subnet mask is – 255.255.255.192. And our network will be – 192.168.1.128/26 because we had block size in the previous network – 128.

Class B subnetting.

Class B subnetting.

Class B subnetting:

In the case of networking, we need to select class-b if both its IP number and the number of network icons are equal. Let's see how to subnet Class B. When subnetting a Class B address, remember that the first two octet 3 bits in the mask must be 1. That is, the first 4-bit is the network and the next 16-bit is the host ID. The Class B default subnet mask is 255.255.0.0. In the case of Class B, we do a bit on the subnetting.

172.16.0.0/17 255.255.128.0 Network Number = 2 = 2 Host Number = 2-15-2= 32766 Subnet Id=256-128=128

Network-1	172.16.0.0	Network-2	172.16.128.0
Fast Host	172.16.0.1	Fast Host	172.16.128.1
	172.16.0.2		172.16.128.2
	172.16.0.3		172.168.128.3
Last Host	172.16.127.254	Last Host	172.16.255.254
Brad cost address	172.16.127.255	Brad cost address	172.16.255.255

Again, in the case of Class B, subnetting two bits on. 172.16.0.0/18 255.255.192.0 Network number 2 = 8 host number = 2 = -2 = 16382 subnet ID = 256-128

Network-3	172.16.128.0	Network-4	172.16.192.0
Fast Host	172.16.128.1	Fast Host	172.16.192.1
	172.16.128.2		172.16.192.2
	172.16.128.3		172.16.192.3
Last Host	172.16.191.254	Last Host	172.16.255.254
Brad cost address	172.16.191.255	Brad cost address	172.16.255.255