IMPLEMENTATION OF DHCP IN CISCO PACKET TRACER

Dynamic Host Configuration Protocol (DHCP) is a networking management protocol used to dynamically assign an IP address to any new node or device entering the network. DHCP permits a node to be configured automatically, thereby avoiding the necessity to involvement by a network administrator. DHCP can be implemented on small local networks as well as large enterprises networks.

DHCP runs at the ppplication layer of the transmission control protocol/IP (TCP/IP) protocol stack to dynamically assign IP addresses to connected devices.It is a client-server protocol in which server manage a pool of unique IP addresses, as well as information about client configuration parameters, and assign addresses out of those address pools.

Visual view of DHCP process:

DHCP process

ADVANTAGES OF DHCP :

• It reduces manual configuration time of IP addresses.
• The implementation does not require any additional costs.
• duplicate or invalid IP addresses are prevented. Hence there is no chance of conflicts in IP addresses.
• It simplifies administration of the network.

                                                          DHCP network topology

STEPS: 

1. Firstly take 2 PCs, a switch (2960) and a router(1941). Select end device option and drag two             generic PCs into the work space. Connect all the PCs using copper straight wire to the switch and       switch to the router as shown in above figure in fast ethernet port.

                 

2. CONFIGURATION :

Router>en
Router#config t
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#int gig 0/1
Router(config-if)#ip address 192.168.1.2 255.255.255.0
Router(config-if)#no shut

Router(config-if)#
%LINK-5-CHANGED: Interface GigabitEthernet0/1, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up

Router(config-if)#exit
Router(config)#ip dhcp pool IP1
Router(dhcp-config)#net 192.168.1.0 255.255.255.0
Router(dhcp-config)#default 192.168.1.100
Router(dhcp-config)#exit
Router(config)#ip dhcp exc 192.168.1.2 192.168.1.10
Router(config)#exit

                                                     Configuration of DHCP on CLI

OSPF PROTOCOL CONFIGURATION IN CISCO PACKET                                         TRACER

Router connect networks using the Internet Protocols (IP), and OSPF (Open Source Path First) is a router protocol used to find the best path for packets as they pass through a set of connected networks. It is also an Internet Gateway Protocol (IGP) for the Internet, used to distribute IP routing information throughout a single Autonomous System (AS) in an IP network.

                                    

The OSPF protocol is a link-state routing protocol, which means that the routers exchange topology information with their nearest neighbors. The topology information is flooded throughout the AS, so that every router within the AS has the complete picture of the topology of the AS. This picture is used to calculate end-to-end paths through the AS, normally using Dijkstra algorithm. The main advantage of link state routing protocol like OSPF is that the complete knowledge of topology allows routers to calculate routers that satisfy particular criteria.

OSPF protocol network topology

CONFIGURATION:

Router 1

Router>enable

Router#config t

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#router ospf 1

Router(config-router)#network 192.168.100.0 0.0.0.255 area 1

Router(config-router)#network 10.10.10.10 0.255.255.255 area 1

Router(config-router)#exit

Router(config)#

Router 2

Router>enable

Router#config t

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#router ospf 2

Router(config-router)#network 192.168.200.0 0.0.0.255 area 2

Router(config-router)#network 10.10.10.20 0.255.255.255 area 2

Router(config-router)#exit

Router(config)#

The configuration steps are shown below using CLI interface

OSPF configuration for router 1

OSPF configuration for router 2

  RIP PROTOCOL CONFIGURATION IN CISCO PACKET                                               TRACER

The Routing Information Protocol, or RIP, as it is more commonly called, is one of the most enduring of all routing protocols. It is distance-vector routing protocol that uses hop count as the metric for path selection. When RIP is enabled on an interface, the interface exchanges RIP broadcasts with neighboring devices to dynamically learn about and advertise routes.

RIP uses broadcast UDP data packets to exchange routing information. Cisco software sends routing information updates every 30 seconds. If a device does not receive an update from another device for 180 seconds or more, the receiving device marks the routes served by the non routing devices as unusable. If there is still no update after 240 seconds, the device removes all routing table entries for the non updating devices.

RIP configuration for router 1

                                                           RIP configuration for router 2

CONFIGURATION:

Router>en

Router#config t

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#int gig 0/1

Router(config-if)#ip address 192.168.100.1

% Incomplete command.

Router(config-if)#ip address 192.168.100.1 255.255.255.0

Router(config-if)#no shut

Router(config-if)#

%LINK-5-CHANGED: Interface GigabitEthernet0/1, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up

Router(config-if)#exit

Router(config)#int se 0/1/0

Router(config-if)#ip address 10.10.10.10 255.0.0.0

Router(config-if)#no shut

Router(config-if)#

%LINK-5-CHANGED: Interface Serial0/1/0, changed state to up

Router(config-if)#ip route 192.168.200.0 255.255.255.0 10.10.10.20

Router(config)#exit

Repeat the above steps for 2nd router also.

             Configuration of Routers in CISCO Packet Tracer

Router: 

A router is a device that analyzes the contents of data packets transmitted within a network or to another network. Routers determine whether the source and destination are destination are on the same network or whether data must be transferred from one network type to another, which requires encapsulation the data packet with routing protocol header information for the new network type.

Advantages of Router:

• It provides connection between different network architectures.
• It can choose best path across the inter network using dynamic routing algorithms.
• It provides sophistication routing, flow control and traffic isolation.
• They are configurable which allows network manager to make policy based on routing decisions.

                                                      Configuration of Router

Configuration of Router:

•  Configuration of Fast Ethernet Interface:
• Type enable (enters global configuration mode)
• Type config t (enters into configuration mode)
• Type int gig slot/port (configures gigabit port)
• Type ip address ip_address (configures IP address to the network)
• Type no shut (changes the gigabit ethernet state to up)
• Type exit (exits configuration mode)
• Router Configuration:
• Type config t (enters into configuration mode)
• Type ip route {destination address} {subnet mask} {next hop adrdess}
• Type end (Exit the router configuration)

REPEAT ABOVE STEPS FOR ALL THE ROUTERS.

Click here for more details.

Configuration of VLAN in Cisco Packet Tracer

A VLAN is a switched network that is logically segmented by function, project team, or application, without regard to the physical location of the user. VLANs ave the same attributes as physical LANs but you can group and stations even if they are not physically located on the same LAN segment. Any switch module port can belong to a VLAN, and unicast,  broadcast, and multicast packets are forwarded or flooded only to the end stations in the VLAN.

Advantages of VLAN:

• Solve broadcast problem.
• Make device management easier.
• Reduce the size of broadcast domains.
• Allow us to implement the logical grouping of devices by function instead of location.

VLANs

Configuration of VLANs:

• Enter into terminal 
• Type enable (Enters into CLI)
• Type config t (Enters into configuration mode)
• Type vlan vlan_id (Creates a VLAN)
• Type name vlan_name (Assigns name to the VLAN)
• Type no shut (Change the interface state to up)
• Type exit (Exits from VLAN configuration)
• Type config t (Enters into configuration mode)
• Type int fa0/i where 1<=i<=24 (Add port to newly created VLAN)
• Type switchport access vlan vlan_id (It adds fa0/i to the VLAN just created above)

Click here to know more about VLAN Configuration in Cisco Packet Tracer.