This is a comparison and explanation of network switching devices. The time constraints is only 15 minutes and only covers the general idea of all devices.
2. What is network switching?
➔ A network device to connect segments within a network
➔ receive messages and send only to the targeted devices
➔ Type of Switch:
◆ Layer 1 Switch or Hub
◆ Layer 2 Switch
◆ Layer 3 Switch
◆ Layer 4-7 Switch (MultiLayer Switch)
3. Network Devices & OSI Layer
Association
OSI Layer
Layer Name
Devices
4-7
Transport, Session,
Presentation,Application
Multi-Layer Swtich
3
Network
Routers, Layer 3 Switch
2
Data Link
Switches, Bridges, NIC’s
1
Physical
Hub or Layer 1 switch
4. Layer 1 Switch
Hub
➔ port mirroring
◆
send network packages from one switch port to another port
➔ can’t filter messages. propagate to all connected
devices
➔ not intelligence to find out best path
for data packets.
5. Layer 2 switch
➔ perform bridging (Bridge with multiple ports )
➔ Store & Forward Switch
◆
◆
perform error-checking before sending network frames
highly reliable & slow
➔ Cut Through Switch
◆
◆
◆
No error checking
look up destination and forward it
performance penalty
6. Layer 2 switch
➔ Fragment Free Cut Through Switch
◆
◆
forward all frames initially
if particular ports get many error frames, switch to store & forward
mode
➔ Unmanaged/Intelligence Switch
◆
◆
tracks & reports performance statistics
have DB ASIC
7. Layer 3 switch
➔ layer 2 switch- filter & forward frames
➔ layer 3 switch- routing capability
◆
◆
each ports is separate LAN port
difference with router: physical implementation
8. Layer 4 Switch
Session,Content switch
➔ responsible for the analysis and control of network
traffic at transport layer
➔ vendor dependent
➔ can include firewall,IP security Gateway,Policy based
routing & ACLs
➔ E.g. Cisco 3560 L4 Switch
◆
L2 switching, L3 routing & L4 content regarding
forwarding, dropping, prioritizing, packets carrying