Routers are basically used to connect different networks by allowing them to exchange routing information with each other. A router is a network layer device that maintains a database called an IP routing table by learning the ip addresses of directly connected networks by default. After enabling the IP Routing process, the learned networks can also be seen in the IP routing table by exchanging the IP routing information.
Cisco is the worldwide leader in providing routers, switches, and other networking devices. Cisco routers are known as the best solution for any type of WAN environment. Cisco routers are manageable devices with a command line interface based Cisco IOS software. The Cisco IOS software is a command line interpreter to perform different commands generating any type of output.
Cisco Router Series
Cisco introduces different series of routers in order to provide industry solutions. The series vary by capabilities, port density, and IOS software. The Cisco router series provide solutions for three types of environments. First is the home office solution or telecommuter solution. In this category, the Cisco router 700 series, 800 series, and 1000 series are included. The second is the branch office or small office solution starting from the 1600 series modular router, including the 2500 series router, 2600 series modular router, and 3600 series modular router. The third category is the head office or central site solution including 5300 series AS, 7200 series modular router, and 12000 series GSR router.
Here are the different Cisco Router series most commonly used in the industry for different type of solutions:
- Cisco 700 series router with an ISDN BRI port
- Cisco 1000 series router with an ISDN BRI port
- Cisco 1600 series router with an extra unscratched module
- Cisco 2500 series branch office solution router with one AUI Ethernet and two serial ports
- Cisco 2600 series modular router with an unscratched WAN Interface Card (WIC)
- Cisco 3600 series modular router with the support of FXO and FXS Voice port
- Cisco 5300 series Access Server router with Async port
- Cisco 7200 series central site solution router with multiple unscratched modules
- Cisco 12000 high end series router with GSR capabilities
Cisco Router Configuration Commands
Users have to know the basic configuration of a Cisco router with the Cisco IOS configuration commands and the operational Cisco router commands in order to execute the performance of any internetwork.
Here are some basic cisco router configuration commands along with operation commands of routers:
- IP address [address][subnet mask]: This command is used to configure the ip address of the specific interface of the cisco router
- Hostname [name]: This command is used to assign a hostname to the cisco router
- Line vty 0 15: This command is used to enter in the line vty configuration mode of the cisco router
- Line con 0: This command is used to enter the line console configuration mode of the cisco router
- Line aux 0: This command is used to enter the line auxiliary configuration mode of the cisco router
- Login: This command tells to ask for the password of a line of the cisco router
- Password [password]: This command is used to set the password of a line of the cisco router
- Enable password [password]: This command is used to set the password to enter in the privileged exec mode of the cisco router
- Enable secret [password]: This command is used to set the encrypted password to enter in the privileged exec mode of the cisco router
- Configure terminal: This command is used to enter in the global configuration mode of the cisco router
- Show interfaes serial 0: This command displays the status of a specific interface of the cisco router
- Show interfaces: This command displays complete information about all the interfaces in the cisco router
- Show ip interface brief: This command displays the brief ip configuration of all the interfaces of the cisco router
- Show running-config: This command displays the status of RAM and the current configuration of the cisco router
- Show ip route: This command displays the IP routing table of the cisco router
- Show startup-config: This command displays the status of NVRAM, the saved configuration of the cisco router
- Show version: This command displays the hardware and software status of the cisco router
- Show flash: This command displays the files and directories in the flash of the cisco router
- Show history: This command displays the last ten commands that were performed in the cisco router
- Erase startup-config: This command is used to erase the saved configuration of the cisco router.
Assigning IP Addresses to a Cisco 2509 Router
Routers have different interfaces and each interface connects with a network. Therefore, each interface should have its own IP configurations. To assign IPs to the Cisco 2509 router, perform this set of commands:
Router2509 (config) # interface serial 0
Router2509 (config-if) # ip address 10.0.0.1 255.0.0.0
How to Configure a New Cisco Router
Configuring a Cisco router is very simple. The Cisco router’s console port should be connected with the computer’s com port with the UTP roll over cable. After the physical connection is made, open Hyper Terminal to make a session and give any name to it. The com port must be on Restore Default settings in the properties of com port and press the Enter key. The Cisco router’s setup mode will run on the terminal. Go through the setup mode with the help of configuration dialogue. The basic configuration includes the configuring of hostname, configuring the enable secret password, enabling password and the line vty password, and the configuration of each interface of the Cisco router.