Free Cisco Ccna, Ccnp, Ccent Tutorial on Switching, Spanning-tree Protocol (stp)
A Layer 2 switch, which functions as a transparent bridge, offers no additional links for redundancy purposes. To add redundancy, a second switch must be added. Now two switches offer the transparent bridging function in parallel. LAN designs with redundant links introduce the possibility that frames might loop around the network forever. These looping frames would cause network performance problems.
For example, when the switches receive an unknown unicast, both will flood the frame out all their available ports, including the ports that link to the other switch, resulting in what is known as a bridging loop, as the frame is forwarded around and around between two switches. This occurs because parallel switches are unaware of each other. The Spanning-Tree Protocol (STP), which allows the redundant LAN links to be used while preventing frames from looping around the LAN indefinitely through those redundant links, was developed to overcome the possibility of bridging loops. It enables switches to become aware of each other
so that they can negotiate a loop-free path through the network. Loops are discovered before they are opened for use, and redundant links are shut down to prevent the loops from forming. STP is communicated between all connected switches on a network. Each switch executes the Spanning-Tree Algorithm (STA)
based on information received from other neighboring switches. The algorithm chooses a reference point in the network and calculates all the redundant paths to that reference point. When redundant paths are found, STA picks one path to forward frames with and disables or blocks forwarding on the other redundant paths.
STP computes a tree structure that spans all switches in a subnet or network. Redundant paths are placed in a blocking or standby state to prevent frame forwarding. The switched network is then in a loop-free condition. However, if a forwarding port fails or becomes disconnected, the STA will run again to recomputed the Spanning-Tree topology so that blocked links can be reactivated. By default, STP is enabled on all ports of a switch. STP should remain enabled in a network to prevent bridging loops from forming.
Related Tags: ccna, ccnp, stp, ccna tutorial, ccent tutorial, ccnp tutorial, spanning tree protocol, switching tutorial
Free Practice Exams are available to help you pass CCNA Exams on first try. Also, Please visit CCNA Jobs to find a better job.
Your Article Search Directory : Find in ArticlesRecent articles in this category:
- Offshore it Consulting Services India
Cost effectiveness of productions offers a cutting edge in this age of stiff competition. Lower is - Geeks Who?
Geeks are characterized by the tools they use. What all one should have to qualify to be called gee - Now Wi-fi (vi-fi) in Vehicles
This is a Wi-Fi age. Those who need can find Wi-Fi hotspots everywhere; in home, hotels, airport lo - How Web Development Can Catalyze Your Profit Prospective?
Website is the heart and soul of an online business. It depicts the appearance of your products, se - Windows Vista Sidebar, Gadgets, Easy Wireless Networking and Improved Back Features
Microsoft has tried to put "active" items on the Windows desktop for nearly a decade. Finally, with - Comptia A+, Network+ Certification Tutorial - Function of Network Hubs
A hub is a device used to connect all of the computers on a star or ring network. A hub is nothing - Windows Vista Features and Upgrading the Windows Vista Versions
Microsoft Windows Vista is the latest workstation version of the Windows operating system and is de - Comptia A+, Security+, Network+ Tutorial - Ethernet Card Troubleshooting
When a computer fails to communicate, the network interface adapter can be at fault, but it is far - Unlock Iphone Tutorial
Most of the people consider that it is difficult to unlock iPhone, but in fact, this process is eas - Tips for Unlock Iphone 3G
Anybody who owns an iPhone wants to have it unlocked and they need unlock iPhone 3G tips, in genera
Most viewed articles in this category:
- It Consulting - Buyer Fraud Prevention
Hiring the wrong computer consultant is not only frustrating, but it can also leave you cheated of y - San Francisco Web Design and Web Development Services
A San Francisco Web Development and Web Design Services, #10 offers a full range of marketing and we - Complex Issues, Comprehensive Solutions by Freelance Providers
As business increases, customers are most certainly asking for their share of higher business value, - Gaming and Graphic Design Computer Monitor Solutions
CRT screens are fast moving towards obsolescence and are now almost the preserve of Graphic designer - Help Wanted - One New Customer for Growing IT Business
Your computer services business is the same, you need customers. But do you need as many as you thin - What Does it Take to be a Top IT Manager Today
Well-Run Concepts has been conducting research on how we can quantify what personal skills or compet - What Are Hosted Applications?
As access to the Internet becomes more widespread with faster, more reliable and 'always on' connect - Password Security
In the past I've never really paid much attention to security issues when it comes to user names and - General Computer Maintenance For The Masses
Reorganizing the file systemGo to “Start” > “Run” > Type in “def - How Does Human Resource Management in the Workspace Effect Me?
How often do you find yourself saying: "I wish I knew how to learn more about this topic" Well, w
