Networking Devices Comparison of the Network layer at which Switch Router Hub Bridge Repeater operate Wireless Access

Size: px

Start display at page:

Download "Networking Devices Comparison of the Network layer at which Switch Router Hub Bridge Repeater operate Wireless Access"

Jasmine Williams
9 years ago
Views:

Networking Devices Network devices are components used to connect computers or other electronic devices together so that they can share files or resources like printers or fax machines.

1 Networking Devices Network devices are components used to connect computers or other electronic devices together so that they can share files or resources like printers or fax machines. Devices used to setup a Local Area Network (LAN) are the most common types of network devices used by the public. A LAN requires a hub, router, cabling or radio technology, network cards, and if online access is desired, a high-speed modem. Comparison of the Network layer at which Switch Router Hub Bridge Repeater operate Wireless Access Hub Bridge Switch Router Point Network Layer 1 (Physical) 2 (Data) 2 (Data) or 3 (Network) 3 (Network) 1 (Physical) or 2 (Data) Repeater 1 (Physical), 2 (Data) or 3 (Network) 1. Hub A hub is a device that connects a number of computers together to make a LAN. The typical use of a hub is at the center of a star network (or as part of a hybrid network) - the hub has cables plugged into it from each computer. The basic form of concentrator is the hub.

Comparison and properties of a Hub A Hub is the simplest of these devices out of the five compared. Hubs cannot filter data so data packets are sent to all connected devices/computers.

2 Comparison and properties of a Hub A Hub is the simplest of these devices out of the five compared. Hubs cannot filter data so data packets are sent to all connected devices/computers. The device has to make decision if it needs the packet. This can slow down the network overall. Hubs do not have intelligence to find out best path for data packets. This leads to inefficiencies and wastage. Hubs are used on small networks where data transmission is not very high. 2. Switch Switch are a special type of hub that offers an additional layer of intelligence to basic, physical-layer repeater hubs. A switch must be able to read the MAC address of each frame it receives. This information allows switches to repeat incoming data frames only to the computer or computers to which a frame is addressed. This speeds up the network and reduces congestion. Switch operate at both the physical layer and the data link layer of the OSI Model.

Comparison and properties of a Switch A switch when compared to bridge has multiple ports. Switches can perform error checking before forwarding data.

3 Comparison and properties of a Switch A switch when compared to bridge has multiple ports. Switches can perform error checking before forwarding data. Switches are very efficient by not forwarding packets that error-ed 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 subnet. 3. Bridge A bridge is used to join two network segments together, it allows computers on either segment to access resources on the other. They can also be used to divide large networks into smaller segments. Bridges have all the features of repeaters, but can have more nodes, and since the network is divided, there is fewer computers competing for resources on each segment thus improving network performance. Bridges can also connect networks that run at different speeds, different topologies, or different protocols. But they cannot, join an Ethernet segment with a Token Ring segment, because these use different networking standards. Bridges operate at both the Physical Layer and the MAC sub-layer of the Data Link layer.

Comparison and properties of a Bridge A bridge is more complex than hub. A bridge maintains a MAC address table for both LAN segments it is connected to.

4 Comparison and properties of a Bridge A bridge is more complex than hub. A bridge maintains a MAC address table for both LAN segments it is connected to. Bridge has a single incoming and outgoing port. Bridge filters traffic on the LAN by looking at the MAC address. Bridge looks at the destination of the packet before forwarding unlike a hub. It restricts transmission on other LAN segment if destination is not found. Bridges are used to separate parts of a network that do not need to communicate regularly, but need to be connected. 4. Router Router Are networking devices used to extend or segment networks by forwarding packets from one logical network to another. Router are most often used in large internetworks that use the TCP/IP protocol suite and for connecting TCP/IP hosts and local area networks (LANs) to the Internet using dedicated leased lines.

5 Comparison and properties of a Router A router, like a switch forwards packets based on address. A router uses the IP address to forward packets. This allows the network to go across different protocols. Routers forward packets based on software while a switch (Layer 3 for example) forwards using hardware called ASIC (Application Specific Integrated Circuits) Routers support different 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. The router has a public IP address and that address is shared with the network. When data comes through the router it is forwarded to the correct computer. 5. Gateway A gateway is a device used to connect networks using different protocols. Gateways operate at the network layer of the OSI model. In order to communicate with a host on another network, an IP host must be configured with a route to the destination network. If a configuration route is not found, the host uses the gateway (default IP router) to transmit the traffic to the destination host. The default t gateway is where the IP sends packets that are destined for remote networks. If no default gateway is specified, communication is limited to the local network. Gateways receive data from a network using one type of protocol stack, removes that protocol stack and repackages it with the protocol stack that the other network can use.

6 6. NICs (Network Interface Card) Network Interface Card, or NIC is a hardware card installed in a computer so it can communicate on a network. The network adapter provides one or more ports for the network cable to connect to, and it transmits and receives data onto the network cable. Wireless Lan card Network card Every networked computer must also have a network adapter driver, which controls the network adapter. Each network adapter driver is configured to run with a certain type of network adapter. 7. WAPs (Wireless Access Point) A wireless network adapter card with a transceiver sometimes called an access point, broadcasts and receives signals to and from the surrounding computers and passes back and forth between the wireless computers and the cabled network. Access points act as wireless hubs to link multiple wireless NICs into a single subnet. Access points also have at least one fixed Ethernet port to allow the wireless network to be bridged to a traditional wired Ethernet network.

Comparison and properties of a Wireless Access Point Wireless Access Point bridges wireless and wired traffic. Wireless Access Point allows devices/computers to connect to LAN in a wireless fashion.

7 Comparison and properties of a Wireless Access Point Wireless Access Point bridges wireless and wired traffic. Wireless Access Point allows devices/computers to connect to LAN in a wireless fashion. Wireless Access Point allows wired and wireless devices work to communicate with each other. 8. Repeater Comparison and properties of a Repeater Repeaters are built into the hubs or switches. Repeaters clean, amplify and resend the signals that have been weakened due to long cables traveling large distances. 9. Modem A modem is a device that makes it possible for computers to communicate over telephone lines. The word modem comes from Modulate and Demodulate. Because standard telephone lines use analog signals, and computers digital signals, a sending modem must modulate its digital signals into analog signals. The computers modem on the receiving end must then demodulate the analog signals into digital signals. Modems can be external, connected to the computers serial port by an RS-232 cable or internal in one of the computers expansion slots. Modems connect to the phone line using standard telephone RJ-11 connectors.

Computer Networks. Definition of LAN. Connection of Network. Key Points of LAN. Lecture 06 Connecting Networks

Computer Networks. Definition of LAN. Connection of Network. Key Points of LAN. Lecture 06 Connecting Networks Computer Networks Lecture 06 Connecting Networks Kuang-hua Chen Department of Library and Information Science National Taiwan University Local Area Networks (LAN) 5 kilometer IEEE 802.3 Ethernet IEEE 802.4