【 Weak current College 】 switches, hubs, routers, difference and use description

Switches, hubs, routers, function?, what is the difference between? first, HUB, or hub. It can be simple read as
Some machines are connected to form a local area network. And switches (also called switching hub) role and the hub in much the same. But the two differ in performance: Hub share bandwidth with the type of work, and the switch is a dedicated bandwidth. This machine a lot or data volume is large, there will be more obvious. While the router and the above two distinct, its role is to connect different segments and find network data transfer on the most appropriate path, you can say in general individual user needs. Router is generated after the switch, the switch is derived from the hub, router and switch also has certain links that are not completely independent of the two devices. Router main overcomes switch cannot route forwarding packets. Overall, the routers and switches the main differences are reflected in the following areas:

(1) work on different levels

The initial switch is working in the OSI/RM-open architecture of the data link layer, Layer II, and the router first design work at the network layer of the OSI model. Because the switch work in OSI layer 2 (data link layer), so it works relatively simple, but the router is working in the OSI layer 3 (network layer), you can get more protocol information, routers can forward to make more intelligent decisions.

(2) data forwarding is based on the object a different

Switch is the use of physical address or MAC address to determine the destination address of forwarded data. While the router is using a different network ID number (IP address) to determine the data forwarding address. IP addresses are implemented in software, describes the device's network, sometimes the third layer address is also known as Protocol address or network address. MAC addresses are usually hardware comes with the manufacturer of the adapter to assign and is intrinsic to the NIC, generally cannot be changed. The IP address is usually represented by a network administrator or system automatically assigned.

(3) traditional switches can only split collision domain, you cannot split a domain of broadcasting; and routers can split the broadcast domain

Segment by the switch connections are still part of the same broadcast domain, broadcast packets will switch on the dissemination of all network segments, and in some cases cause traffic congestion and security vulnerabilities. Connect to router on the network segment will be assigned to different broadcast domains, broadcasting data does not pass through routers. Although the layer 3 switches have VLAN function above, or you can split the broadcast domain, but the child is between the broadcast domain cannot communicate communicating communication between them, still need a router.

(4) router provides the firewall service

Router just forward packets for a specific address, not shipping does not support routing protocol packets and unknown destination network packet delivery, which can prevent a broadcast storm. Switch generally used for the connection, switch LAN-WAN attributable to the bridge, is the data link layer device, some switches can also be achieved the third layer of Exchange. The router for the connection between WAN-WAN, can solve specific network forward group, role in the network layer. They just from a single line accept input group, and then to another line to be forwarded. These two lines may belong to different networks using different protocols. In comparison, the router features a switch to powerful, but slower speed correspondingly expensive, layer 3 switch existing switch wire-speed packet forwarding, and router a good control features, widely used. Currently individuals more broadband access is ADSL, ADSL access author to simple. Now buy ADSL cat mostly with routing features (many of the manufacturers in the factory the routing function shield, because most of the Telecom installation is not enabled for routing capabilities that enable DHCP. ADSL routing feature), if the personal Internet access or a few computers through ADSL itself, if the computer more you only need to purchase one or more of the hub or switch. The remaining to do only the machine's network cable into the switch interface, cat cable into uplink interfaces. And then set the routing functionality, such as DHCP, you can share online. Read more commentary readers should switches, hubs, routers, have some understanding of current use mainly for switches, routers use a combination of the primary, the specific combinations according to the specific situation and needs of the network.