How do you use a very similar network device "router" and "L3 switch"?

Both routers and layer 3 (L3) switches are devices for communication beyond the LAN.Therefore, it has a routing function.The routing is to sort the packet according to the destination when multiple networks are connected.Multiple networks refer to networks divided by external networks (WAN), such as LAN, Internet, and departments.

The use is different between the router and the L3 switch.The router is mainly installed at the border between LAN and WAN.The L3 switch is installed in the LAN and used as a switch connecting the internal network.Both have not only routing but also other functions that match the application.

The router will be installed on the boundary of DMZ, which has a public server such as LAN and WAN, WEB and email.It generally has NAT and NAPT functions to convert IP addresses to exchange packets between WAN or DMZ, which uses a LAN and global IP address using a private IP address.

Many products have a VPN function that builds a virtual closed network with other bases using the Internet, and a security function to prevent unauthorized intrusion from outside.Router products that combine these functions are called UTMs and next -generation firewols.

On the other hand, the L3 switch has a VLAN function that logically divides LAN in units such as departments and floors.By using VLANs, the broad -cast domain can be narrowed, the congestion of the network can be reduced, and the range of problems such as loops can be restricted.

The routing of the L3 switch is used to connect the split VLANs.However, packet transfer between VLANs often emphasizes security and limits it to "only allow access to specific servers".

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