network switch and switching jenil patel semcom college
TRANSCRIPT
Agenda
1. About Network Switch
2. Network Switch Photo
3. How SWITCH Work ?
4. Types Of Network Switches and Switching
5. Network Switch Benefits
About Network Switch
• A network switch is a small device that joins multiple computers together within one local area network (LAN).
• Multi-port network bridge
• Technically , network switch operate at layer two (data link layer) of the OSI model.
• Switching that additionally process data at the network layer (layer 3) and above are often referred to as layer-3 switches or multilayer switches.
• Receives a message from any device connected to it and then transmits the message only to that device for which the message was meant.
• More intelligent device than a hub ( which receives a message and then transmits it to all the order devices on its network).
• Integral part in most modern Ethernet local area network (LANs)
How SWITCH work ?
A B C D E
• Technically speaking hubs operate using a broadcast model and
switches operate using a virtual circuit model. when five computer
are connected (A,B,C,D,E) Hub . For example , and two of those
computer communicate with each other , hubs simply pass through
all network traffic to each of the five computers .
• Switches , on other hand , are capable of determining the
destination of each individual traffic element (such as an Ethernet
frame) and selectively forwarding data to the one computer that
actually needs it. By generating less network traffic in delivering
messages, a switch performs better than a hub on busy network.
Switch data sharing speed 100mbps.
Types of Network Switches or Switching
• There are four forwarding methods a bridge or Switch can use
1. Store and Forward
2. Cut through
3. Fragment Free
4. Adaptive Switching
1.Store and Forward Switch
• The switch buffer and verifies each frame before forwarding it.
• Check the error
• This type of switch very slow compare other one .
2.Cut Through Switch
• The switch reads only up to the frame’s hardware address before starting to forward it.
• There is no error checking with this method.
• This type of switch is very fast compare other type of switch
3.Fragment free switch
• A method that attempts to retain the benefits of both store and forward and cut through .
• Fragment free check the first 64 bytes of the frame ,where addressing information is stored.
According to Ethernet specification,
• Collision should be detected during the first 64 bytes of the frame ,so frames that are in error because of a collision will not be forwarded.
• This way the frame will always reach its intended destination .
• Error checking of the actual data in the packet is left for the end device.
4.Adaptive switch
• A method of Automatically selecting between the other three modes.
• Maximum use Store and Forward Switch
The second through fourth method were performance-increasing methods.
When used with the same input and output port bandwidths.
Network Switch Benefits
• High-speed data exchange
• Full-duplex communication
• Low latency
• Dedicated communication between devices