Saturday, February 13, 2010

What is the Lan Switches and Packet-switched Network

By: Zahid Mahmood

Ethernet, Fast Ethernet, FDDI and Token Ring often referred to as traditional LAN, and they are sharing media, sharing of bandwidth shared LAN. In order to increase bandwidth, often using a network router division, will be divided into a network of more than one paragraph, each of the networks have different sub-address, different broadcasting domain, to reduce conflicts on the network, increase network bandwidth. Micro-paragraph of the network can not meet the LAN extension and the new high-bandwidth network applications to the demand, it is said that "traditional local area network has come to an end."




In recent years the exchange processes-LAN technology, to address shared by the LAN network inefficient and can not provide adequate network bandwidth and network expansion and a series of difficult issues. It fundamentally changed the structure of shared local area network, to solve the bandwidth bottleneck. At present, the exchange of Ethernet, token ring exchange, the exchange of FDDI and ATM, such as the exchange of local area networks, Ethernet one of the most extensive exchange. LAN exchange has become the mainstream LAN technology.




Switches provide the ability to bridge the existing network and increase bandwidth capabilities.




For the LAN switches on the bridge with similar because they all operate in the data link layer (level 2), M A C-layer, the inspection of all network traffic into the device address. And the bridge still has some similar switch to maintain an address on the table and used the information to decide how to filter and forward LAN flow.




And bridge different, switches using technology to increase the exchange of data input and output media and installation of the total bandwidth. General switch delay small forward, the economy and can be divided into small network of conflict domain, for each workstation to provide higher bandwidth.




Packet-switched network is the circuit-switched networks and packet switching network after a new exchange network, which mainly used for data communications. Packet switching is a store-and-forward of the exchange, it will at the user's text is divided into a certain length of the packet to packet for store-and-forward, therefore, than the utilization of circuit-switched, than when the message exchange Extensions to small, but with real-time communication capabilities. Packet-switched TDM principle of the use of statistics, a data link multiplexing into multiple Luojixindao, eventually forming an Caller, Called party transmission of information between the access road, called the VC (VC) to achieve data Packet sent.




Packet switching network has the following characteristics:




(1) packet switching with multiple Luojixindao the capacity utilization rate is high trunk circuits




(2) can be realized packet switching codes of the different online, the rate between the terminal and a point of order Interoperability;




(3) The packet switching error detection and correction of the capacity of the transmission circuit is a very small error rate




(4) packet-switched network-management capabilities.




Packet switching the basic business SVC (SVC) and PVC (PVC) two. SVC as telephone circuit, that is, two data communication terminals to be used when the first call to establish procedures for circuit (VC), and then sent the data, communications rewirable procedures used after the removal of VC. PVC as green, in the net division between the two terminals for the period of the contract to provide permanent logical connection, no call set-up and rewirable procedures, the data transmission phase, with the SVC the same.


About the Author

Zahid Mahmood is the owner of ccnacertificationguide & ccent. Source of free online ccna & ccent study guide and practice exam questions for the prepration of ccna and ccent certifications exam.

(ArticlesBase SC #654015)

Article Source: http://www.articlesbase.com/ - What is the Lan Switches and Packet-switched Network

Monday, February 1, 2010

Easy Guide on Networking Your Home Computers by: Pinky Mcbanon

Easy Guide on Networking your Home Computers

Let's say you have 3 desktop computers at your home. One in your kid's room, in your home-office and one in your family room. Your idea is to have all these 3 computers connect to the internet. One computer has an internet connection on a DSL or cable modem (this is just a terminology for that little box that you connect from the phoneline or cable port!).

So you want all these 3 computers connect to the internet, share files? print from any of this computer?

Here are your step-by-step guide:

(1) Your DSL or cable internet service already comes with a modem. This is a connection from your phoneline to the modem. And then, you will notice your computer#1's network cable directly connect to this modem called the Ethernet port (or on the USB port).

(2) For the other 2 computers to share internet connection, you must have a router with 4 ports (at least!) --- looks like a telephone ports. There are a lot of router brands, one is Linksys and is my favorite. But as I have said there are a lot of different brands out there!

You must buy a network cable if you don't have one. You can buy it from most electronic store.

(4) Here we go! (considering ofcourse we are networking a Window-based computers-- Windows XP (home & professional) and Windows 2000 and higher)

(5) Connect a network cable on your router (port name: "internet" or "ethernet" - this is usually a separated port from the other 4 ports). The other end of the network cable will directly be connected to the DSL or Cable modem's (port name: "ethernet").

(6) Connect a network cable on each computer that you want to get connected to the internet-- (connect this cable at the back of the computer (port name: ethernet).

(7) The other side of each of this network cable will then be connected on each of the port on the router

(8) Now you are ready to be connected! -- turn on your dsl/cable modem. Make sure all lights are on and solid. Turn on your router.

(9) Then turn on your computer(s) -- make sure the light at the back of the computer is blinking! (this is a good sign that you are connected on the network!)

(10) Then set up your router which is normally you choose the proctocol PPoE and just enter your username and password supplied to you by your internet service provider. Oh! by the way, depending on the router, the admin window of the router is on the manual. It's so easy to find it. Trust me.

(11) If your username and password provided to you by your internet service provider is valid... then you should be connected to the internet!.Go and start browsing the internet!

*** most of the routers available in the market now are interlligent routers! There is really nothing complicated on how to set it up. Its entirely DHCP (automatic IP assignment). I don't want to be technical but .. there you go! Enjoy and be safe on the internet! 

Learn About Network Switches and Hubs

Learn About Network Switches and Hubs

By: M. Aslam


TRENDnet 5-Port 10/100Mbps Ethernet Switch TE100-S5 (Blue)
D-Link DGS-2205 5-Port 10/100/1000 Desktop Switch
Linksys by Cisco EZXS55W EtherFast 10/100 5-Port Workgroup Switch
Linksys by Cisco EZXS88W EtherFast 10/100 8-Port Workgroup Switch


Switch has replaced the bridge in the modern network, which is replacing routers in many instances as well. A switch is a box with multiple cable jacks in it that looks a lot like a hub. Some manufacturers have hubs and switches of various sizes that are all but identical in appearance. The difference between a hub and a switch is that while a hub forwards every incoming packet out via all ports, a switch forwards each incoming packet only to the port that offers access to the destination system.

Switches convert the LAN from a shared network medium to a dedicated one. If you have a small network that uses a switch instead of a hub, each packet takes a dedicated path from the source computer to the destination, forming a separate collision domain for those two computers. Switches forward broadcast Messages to all ports, but not unicasts and multicasts. No systems receive packets destined for other systems, and no collisions occur during unicast transmissions. While a bridge reduces unnecessary traffic congestion on the network, a switch all but eliminates it.

Another benefit of switching is that each pair of computers has the full bandwidth of the network dedicated to it. A standard Ethernet LAN using a hub have 20 or more computers sharing the same 10 Mbps of bandwidth. Replace the hub with a switch, and every pair of computers has its own dedicated 10 Mbps channel. This improves the overall performance of the network without the need for any workstation modifications to it. Switches offer ports that operate in Full-duplex mode. Full-duplex operation can effectively double the throughput of a 10 Mbps network to 20 Mbps.
About the Author
M. Aslam is the founder of www.FreeTechExams.com, Central resource for people who are looking for free CCNA and MCSE Practice Exams.
(ArticlesBase SC #587375)
Article Source: http://www.articlesbase.com/ - Learn About Network Switches and Hubs