Networking Hardware

  Home arrow Networking Hardware arrow Page 2 - Router Overview
Watch our Tech Videos 
Dev Hardware Forums 
Computer Cases  
Computer Processors  
Computer Systems  
Digital Cameras  
Flat Panels  
Gaming  
Hardware Guides  
Hardware News  
Input Devices  
Memory  
Mobile Devices  
Motherboards  
Networking Hardware  
Opinions  
PC Cooling  
PC Speakers  
Peripherals  
Power Supply Units  
Software  
Sound Cards  
Storage Devices  
Tech Interviews  
User Experiences  
Video Cards  
Weekly Newsletter
 
Developer Updates  
Free Website Content 
 RSS  Articles
 RSS  Forums
 RSS  All Feeds
Write For Us 
Contact Us 
Site Map 
Privacy Policy 
Support 
 USERNAME
 
 PASSWORD
 
 
  >>> SIGN UP!  
  Lost Password? 
NETWORKING HARDWARE

Router Overview
By: McGraw-Hill/Osborne
  • Search For More Articles!
  • Disclaimer
  • Author Terms
  • Rating: 4 stars4 stars4 stars4 stars4 stars / 129
    2004-08-04

    Table of Contents:
  • Router Overview
  • How Routers Work
  • Packets and Paths
  • Optical Routers and Technologies
  • Communicating with a Router
  • The Console Port
  • Telnet
  • Router Security
  • Enable and Enable Secret Passwords
  • Router Hardware and Memory
  • Router Ports and Modules
  • Router Packaging
  • Essential Files
  • Using TFTP for IOS Backups and Updates
  • The Configuration File

  • Rate this Article: Poor Best 
      ADD THIS ARTICLE TO:
      Del.ici.ous Digg
      Blink Simpy
      Google Spurl
      Y! MyWeb Furl
    Email Me Similar Content When Posted
    Add Developer Shed Article Feed To Your Site
    Email Article To Friend
    Print Version Of Article
    PDF Version Of Article
     
     

    SEARCH DEV HARDWARE

    Router Overview - How Routers Work


    (Page 2 of 15 )

    In a nutshell, routers do exactly what their name says: They route data from a LAN to another router, then another router, and so on until data is received at its destination. Routers also act as traffic cops, allowing only authorized machines to transmit data into the local network so that private information can remain secure. In addition to supporting these dial-in and leased connections, routers also handle errors, keep network usage statistics, and handle security issues.

    Routing for Efficiency

    When you send an e-mail to your Aunt Sadie on the other side of the country, it’s routing technology that ensures she and she alone gets the message, and not every computer hooked up to the Internet. Routers direct the flow of traffic among, rather than within, networks. For instance, let’s consider how routers can be used within a LAN to keep information flowing.

    Design-O-Rama, as shown in Figure 4-2, is a computer graphics company. The company’s LAN is divvied into two smaller LANs — one for the animators and one for the administration and support staff. The two subdivisions are connected with a router. Design-O-Rama employs eight people — four animators and four other staffers. When one animator sends a file to another, the large file will use a great deal of the network’s capacity. This results in performance problems for the others on the network.

     cisco

    NOTE: Remember how Ethernet works. A single user can have such a dramatic impact on the network because each information packet sent by one computer is broadcast to all the other computers on the LAN. Then each computer examines the packet and decides if it was meant for them.

    To keep the animators from constantly slowing down the network, the network was divided into two—one for the animators and one for everybody else. A router links the two networks and connects them both to the Internet. The router is the only device on the network that sees every message sent by any computer on either network. When an animator sends a file to a colleague, the router looks at the recipient’s address and keeps that piece of traffic isolated on that LAN. On the other hand, if the animator wants to query the human relations department about vacation time, the router knows to let that piece of traffic through to the HR department.

    Routers and the Internet

    In our previous example, we examined how a router could be used locally. Now, let’s broaden the scope of what routers do to include their functionality across the entire Internet.

    For the sake of comparison, let’s first talk about how a telephone call is routed across the country. Say it’s Aunt Sadie’s birthday and rather than send an e-mail, you want to call her. When you make a long-distance call, the telephone system establishes a stable circuit between your telephone and Aunt Sadie’s. The circuit may involve hopping through a number of steps, including fiber-optics, copper wires, and satellites. This end-to-end chain ensures that the quality of the line between you and Aunt Sadie will be constant. However, if the satellite goes offline or work crews cut the fiber-optic cable, your conversation with Aunt Sadie will be cut short. The Internet avoids this problem by making its “calls” in an entirely different way.

    mghThis chapter is from Cisco: A Beginner's Guide, by Velte and Velte (McGraw-Hill/Osborne, 2004, ISBN: 0072256354). Check it out at your favorite bookstore today. 
    Buy this book now.

    More Networking Hardware Articles
    More By McGraw-Hill/Osborne

    blog comments powered by Disqus

    NETWORKING HARDWARE ARTICLES

    - ASUS RT-N66U Dark Knight Wireless Router Rev...
    - Belkin Advance N900 Wireless Router Review
    - How to Shop for a Wireless Router
    - How to Change Your Router Password
    - Three Common Home Networking Problems
    - Wireless Security Myths and Five Ways to Sto...
    - Setting Up a Small Business Network
    - Wireless Technology Health Risks
    - Wireless Routers: A Guide for Beginners
    - How to Connect Two Routers on the Same Netwo...
    - What Can the MiFi Do For You?
    - Basic Networking Devices in Layman`s Terms
    - NetGear WGR614 Wireless Router
    - HP ProCurve Switch 2524 J4813A
    - Novatel Wireless Ovation MC950D USB HSPA Mod...

    Developer Shed Affiliates

     




    © 2003-2014 by Developer Shed. All rights reserved. DS Cluster - Follow our Sitemap
    KEITHLEE2zdeconfigurator/configs/INFUSIONSOFT_OVERLAY.phpzdeconfigurator/configs/ OFFLOADING INFUSIONSOFTLOADING INFUSIONSOFT 1debug:overlay status: OFF
    overlay not displayed overlay cookie defined: TI_CAMPAIGN_1012_D OVERLAY COOKIE set:
    status off