difference between hub, bridge, switch and router

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1. Difference between Hub, Bridge, Switch and Router COMMON NETWORK ENVIRONMENTS, CONNECTIVITY AND SECURITY ISSUES 07/01/2015 akmalcikmat

2. Hub Hub is known as the most simplest amongst these device In general, hub is the central part of a wheel where the spokes come together. It cannot filter data. Data packets are sent to all connected devices, and there is no intelligence to find out the best path for data packet which then leads to inefficiencies and wastage. As a network product, a hub may include a group of Modem-cards : for dial-in user a gateway card : for connections to a local area network (LAN) and a connection to a line Hubs are used on a small networks where data transmission is not very high. 07/01/2015 akmalcikmat

3. Summary A common connection point for device in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. 07/01/2015 akmalcikmat Sample Picture : A Network Hub

4. Bridge In a telecommunication networks, a bridge is a product that connects a local area network (LAN) to another LAN that uses the same protocol. Has a single incoming and outgoing port Filters traffic on the LAN by looking at the Media Access Control (MAC) address, thus a bridge is more complex than a hub A bridge looks at the destination of the packet before forwarding unlike a hub. It restricts transmission on other LAN segment if the destination is not found. A bridge works at the data-link (physical network) level of a network, copying a data frame from one network to the next network along the communication path. 07/01/2015 akmalcikmat

5. Bridge 07/01/2015 akmalcikmat

6. Switch When compared to bridge, a switch has multiple ports. Switches can perform error checking before forwarding data, which are very efficient by not forwarding packets that error-end out or forwarding good packets selectively to correct devices only. Switches can support both layer 2 (based on MAC address) and layer 3 (based on IP address) depending on the type of switch . Usually, large networks use switches instead of hubs to connect computers within the same subset 07/01/2015 akmalcikmat

7. Summary In networks, a device that filters and forwards packets between LAN segments. Switches operate at the data link layer (layer 2) and sometimes the network layer (layer 3) of the  OSI Reference Model and therefore support  any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. 07/01/2015 akmalcikmat Sample Picture : Network Switch

8. Router Router forwards packets based on address just like a switch. Routers usually use the IP address to forward packets, which allow the network to go across different protocols. Routers forward packets based on software while a switch forwards using hardware. Eg : Layer 3 uses a hardware called ASIC (Application Specific Integrated Circuits) Routers support different Wide Area Network (WAN) technologies but switches do not. Wireless routers have access point built in. The most common home use for routers is to share a broadband internet connection. As the router has a public IP address which is shared with the network, when data comes through the router, it is forwarded to the correct computer. 07/01/2015 akmalcikmat

9. Summary A  device that forwards  data packets along  networks. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP.s  network. Routers are located at gateways, the places where two or more networks connect. Routers use  headers  and forwarding tables to determine the best path for forwarding the packets, and they use protocols such as ICMP to communicate with each other and configure the best route between any two hosts. 07/01/2015 akmalcikmat Sample Picture : Router

10. Comparison of bridge mode and router mode Photo credited to cisco900router 07/01/2015 akmalcikmat