2007-01-10 16:30:11 · 3 answers · asked by Shiva Kumar M 1 in Computers & Internet ➔ Computer Networking
There are 7 layers in the OSI network diagram, which describes network connections.
Layer 1, the lowest, describe PHYSICAL aspects like the size & shape of the network connector.
Layer 2 describes the DATA link, with things like a a hardware address called Media Access Control (MAC Address)
Layer 3 describes NETWORK stuff like IP addresses.
A layer 2 switch looks at the DATA section of data packets (the MAC address) to determine where to send a packet.
A layer 3 switch looks the the IP address to do the same thing.
The big difference? You can make the IP address anything you want- this can help you "group" machines. Ususally, you have NO control over the MAC address.
2007-01-10 19:12:44 · answer #1 · answered by Alan 6 · 0⤊ 0⤋
layer 3 routes within and between network segments.
layer 2 switches use the ipaddress to move traffic in a 'smart' fashion on one network segment.
One Router per segment, and many layer 2 switches and layer 1 hubs may be used to connect the needed amount of computers.
Layer 3 Routers use 'routing tables' to figure out where to send the packets.
Layer 2 Switches do not recognize routing tables - however it knows which ipaddress is attached to which port - so when a packet comes in on port 1 and the packet header has the ipaddressof the computer or nas or printer on port 8, it sends the packets to the correct port, therefore reducing the steps needed with 'broadcast' to know figure out where to send the packets.
2007-01-11 00:37:31 · answer #2 · answered by T G 4 · 1⤊ 0⤋
Layer 3 incorporates router functionality.
http://www.cisco.com/web/about/ac123/ac147/archived_issues/ipj_1-2/switch_evolution.html
2007-01-11 00:37:24 · answer #3 · answered by david80 2 · 0⤊ 0⤋