A network switch resembles a network hub in appearance. However, network switches are capable of inspecting incoming messages when received, determining the source and destination of each packet and then forwarding data only to the specific devices. While hub transmits the packets to every port except the one which is received the traffic. In general, there is a limit to the amount of bandwidth that users can share on a hub-based network. The more devices are added to the network, the longer it takes data to reach its destination.
A network switch can avoid these and other limitations of hub networks. Network switches create a network while routers connect networks. In other words, network switches allow different devices on a network to communicate, but routers allow different networks to communicate. They can also operate at the network layer--Layer 3 where routing occurs.
In general, though, most switches today use ethernet. The switch uses the MAC address to identify which attached device outgoing packets are being sent from and where to deliver incoming packets. So the MAC address identifies the physical device as opposed to the network layer Layer 3 IP address, which can be assigned dynamically to a device and change over time.
When a device sends a packet to another device, it enters the switch and the switch reads its header to determine what to do with it.
It matches the destination address or addresses and sends the packet out through the appropriate ports that leads to the destination devices. To reduce the chance for collisions between network traffic going to and from a switch and a connected device at the same time, most switches offer full-duplex functionality in which packets coming from and going to a device have access to the full bandwidth of the switch connection.
Picture two people talking on a cell phone as opposed to a walkie-talkie. In order for traffic to get from one subnet to another it must pass between switches, and this is facilitated by routing capabilities built into the switches.
A hub can also connect several devices together for the purpose of sharing resources, and the collection of devices attached to a hub is known as a LAN segment. A hub differs from a switch in that packets sent from one of the connected devices is broadcast to all of the devices that are connected to the hub. With a switch, packets are directed only to the port that leads to the device that packets are addressed to. Switches typically connect LAN segments, so hubs attach to them.
Switches filter out traffic destined for devices on the same LAN segment. Because of this intelligence, switches make more efficient use of their own processing resources as well as network bandwidth. That means the switch itself has no settings or special features, and it exists only to add more Ethernet ports to your network.
Your router continues to handle your Internet connection, letting your devices talk to one another and restricting what certain devices can do through parental controls or other settings—the switch is effectively invisible.
In contrast, the kinds of things that managed switches do—such as monitoring traffic on individual ports or setting up virtual networks VLANs using the same switch—are really important only for large corporate networks.
Because unmanaged switches are so simple, models from different manufacturers all perform about the same. A good mesh-networking kit saves you from needing to run Ethernet cabling through your walls no matter how big or complicated your house is, and it's usually cheaper too.
A switch is just one part of a home wiring project, and you should read a full how-to guide before you decide whether this is something you want to try, even if you plan on hiring a contractor to do the actual wiring. That is why proper traffic segmentation in layer 2 is very important for network security as well as reliability.
Having knowledge of how does switch work and how does router work, you should be able to clearly describe what is going on with an IP packet flowing across the network. IP packet sent across the network from computer A to computer B very likely has to pass several network segments.
Some connected with Ethernet and some with WiFi. Every network segment will use different medium access method so different frame but packet stays the same. Fast growing Grandmetric team is becoming also a referal point in Cloud migrations and DC Stack management with their Storage, OS and virtualization experience. Grandmetric provides technical insights along with technical trainings in areas of expertise. No particular software involved, apart from Powerpoint.
Your email address will not be published. Sign up to our newsletter! Save my name, email, and website in this browser for the next time I comment. Toggle navigation. How does a switch work? Author: Grandmetric. Ethernet Frame Every IP device produces packets and they are forwarded across the network regardless of network access type.
Purpose no. So how does the switch work? Switching process When a frame arrives to a switch, the switch needs to direct the frame out through the right port, this redirection is called switching. Switches and broadcast traffic Switches treat broadcast traffic specifically. Switch and Router on the path Having knowledge of how does switch work and how does router work, you should be able to clearly describe what is going on with an IP packet flowing across the network.
Device A sending IP packet encapsulates it with Ethernet frame Switch switches the frame to the next device which is router, preserving the frame Router looks into IP header stripping decapsulating the frame After choosing right interface to route the packet encapsulates it with WiFi frame Wifi frame comes to device B, device decapsulates frame and interprets the IP packet To see other posts on network and wireless fundamentals see our explained section.
0コメント