Ccna, Ccent, Ccnp Tutorial on Routers and Routing
Routers are the critical part of all the networks and can be both security aid and security vulnerability. A router basically has more network interfaces through which network traffic is forwarded. Or it might be blocked. The router decides when to forward packets between the networks based on internal routing table.
The routing table can also be static. That means where each route is explicitly defined or dynamic where the router learns new routes by the use the routing protocols.
A router also supports access control lists that specify which packets to allow or blocked. Every packet going through a router will be checked against the ACL to see if the packet is allowed to be forwarded. Lots of current routers offer security capabilities along with their routing functionality. Segmenting the network using routers limits the amount of the data flowing through segments. It also applies to broadcast traffic.
Routers also allow technicians to explicitly deny a few packets the ability to be forwarded between segments. Using just the internal security features of some,
routers can prevent users through internal network from using the Telnet to access external systems. Telnet are always a security risk as the passwords and all communications are transmitted in cleartext. Because of this, it's best not to create Telnet sessions between the internal network and an external network. Without a firewall, the rule can be put in place within the router to drop packets attempting to connect to port 23 on any external systems. After all of this is done by properly con- figuring the ACLs for the router. Spoofed packets are packets that contain the IP address in the header that are not the actual IP address of the
originating the computer. Routers combat this by giving the technicians the ability to drop packets which are coming through the interface from the wrong subnet. . If the packet comes in from the router's external interface by using an IP address from the network on the router's internal interface, the router can be instructed to drop the packet and not forward it. There are two types of access lists available to filter traffic on Cisco routers. One of them is a standard access list. It allows technicians to filter traffic from specific addresses or subnet ranges. Cisco also provides extended access lists, which allow technicians to filter based on a variety of criteria. This access list allows technicians to use source addresses, destination addresses, and specific network services as the basis of filtering rules.
Related Tags: ccna, router, routers, routing, ccent, ccna tutorial, ccent tutorial
Learn about CCNA Exam , Vista 64 bit and download vista service pack 1 .
Your Article Search Directory : Find in ArticlesRecent articles in this category:
- 10 Multiple Choice Certification Mcsa Microsoft Exam: 70-291
Implementing, Managing and Maintaining a Server 2003 Network Infrastructure After you study your te - Online Degrees in Animation
The computer animation field has quite a prominent part to play in the entertainment industry. Gami - Comptia Security+ Article on Firewall Security Advantages and Firewall Functions
The firewall protects an internal network from malicious hackers or software on an external network - Free Cisco Ccna Tutorial
The basic boot sequence for a Cisco router is: Step 1: The router performs a power-on self-test (P - Why Switch to Windows Vista
In addition to hype there are some tangible reasons to upgrade and or switch over to Windows Vista. - Why Don't I Make Money on Adsense?
It started for me about four years ago, "Adsense that is" I was like a man possessed, I thought thi - The Growing Fashion of Online Casino
The evolution of online has made your life much easier everywhere. When it comes to the entertainme - Free Cisco Ccna, Ccent, Ccnp Certification Tutorial
Routing Routing is a relay system by which packets are forwarded from one device to another. Each - What is Sociology Dissertation?
Sociology dissertation can be based on a range of topics related with the field of social science a - Learning Made Easier for Children With the Use of Computer Training
Computers are here permanently and will pretty much guide the future of society. This fact mandates
Most viewed articles in this category:
- Taking Ctrl - 20 Keyboard Shortcuts
There may be times when it is simply inconvenient to use the click of your mouse for a specific comm - Windows Keyboard Shortcuts
When I observe most colleagues and friends working on their PC's they mostly use the mouse as they a - How Hackers Take Control of Your Computer
Your PC has many "ports" which are vulnerable to attack from a hacker. These ports are use - How To Succeed At A Computer Training School
One of the best decisions you can ever make is to attend a computer training school. As I've written - Mcse or Mcsa?
Four MCSE, MCSA Tracks are available. The MCSA fcould be considered as a "Mini" version of - 10 Great Tips to a Successful Website
How to make a successful website 1. Make and develop your own website. Do NOT copy or get webs - Protect Your Privacy by Erasing Tracks Left on Your Computer
When you browse the web information is continuously collected by the websites you visit and by your - Seven Steps to Prosperity: Starting Your Own Computer Services Business
Self employment has increased over 12.2 million people according to a study on the Small Business Ad - Computer Training School Tutorial: Know Your Instructor
Making the decision to attend a computer tech school can be one of the best decisions of your life.& - Computer Memory - Flash Memory
That means it does not need power to retain the information that is on the chip itself. Also, flash