The Types Of Modems

Published Date: 02 Nov 2017

10901248 DATCOMM

Routers

A router is a device or software that routes data depending on their designated addresses. A router routes network of devices based on their routing table. It helps in transferring data from one device to another for communication or data transfer. It is powered by a modem and to the devices in which internet is linked to used and shared by users.

Types and Brands

Brands: D-link DI804-HV, Edimax 3G-6200Wg, D-link, Wi-Tribe, Smart, Globe, Sun, Sky, BayanTel, Motorola, Linksys, Microsoft, Dell, Zyxel

Broadband Routers

Broadband routers or residential gateway are used to link computers with high speed Internet service. Broadband routers uses Ethernet for wired connections while others uses wireless networks to connect it to the main system.

 Wireless Routers

Wireless routers are mostly used for users that owns a mobile and portable devices wherein wires can’t be used for Internet connection. By providing a password and determined IP address, wireless router users are protected from others that are not authorized to use the wireless LAN.

 Edge Router

Edge routers or boundary routers are routers that are located at the edge of the ISP network. Edge routers routes data from one LAN to another and are also build up to an external protocol to another.

Core Router

Core Routers are routers that are used in wide computer networks that is located at its center for data management. It handles the flow of data from different networks used by the entire system. It is recognized as a main device within the LAN network.

Modems

Modems can provide a high-speed connection to the Internet. A modulator creates a band pass analog signal from binary data while a demodulator recovers the binary data from the modulated signal.

A device sends a digital signal to the modulator portion of the modem; the data are sent as an analog signal on the telephone lines. The modem receives the analog signal, demodulates it through its demodulator, and delivers data back to the device. The communication can be bidirectional, which means a device can simultaneously send data to the computer on the left, using the same modulation or demodulation processes.

Brands: Globe tattoo, Huawei E392, SmartBro, D-Link, ZyXel, Netopia

Types of Modems

External Modem: A type of modem that is separated from the main system or the device used. By using a cable, the modem is connected from the port on the modem to the internet port of the device. The telephone cable is also connected externally using a jack to the modem.

Internal Modem: An internal modem is a circuit that is already attached to the system unit of the device.

Intelligent Modems: Intelligent modems are advanced modems that can accept dynamic instructions and respond to the orders while transmitting data and information using advanced microprocessor chips.

Short-Haul Modems: By using any COM1 port, short-haul modems transmit data signals. Short- haul modems do not need an external power source. It is widely used in large companies where in the network is used by building to building or any large areas

Wireless Modems: Wireless modems uses electromagnetic waves or radiofrequency waves in order to transmit data packets without using cables or wires. This type of modem is widely used in cellular networks where in the device is mobile or portable.

Switches

Switches series of interlinked nodes that creates temporary connections between 2 or more devices linked to the switch but not to each other.

Switching Methods

Circuit Switching is switching technique that connects unbroken paths between the sender and the receiver directly. It is a switching technology that establishes an electrical connection between stations using a dedicated path. In virtual circuit switching, a phase in which the source and destination use their global addresses to help switches make table entries for the connection.

Message switching is a switching method where in each switch stores the whole message and forwards it to the next switch without using a path. Data messages are sent through a network of nodes, where in each node receives the entire transmitted data message and stores it on its memory before it transmit the message to another node.

Packet Switching is a switching method where in there is no resource allocation for a data packet due to the fact that there is no reserved bandwidth on the links. This method combines message and circuit switching methods. The two types of packet switching method are datagram and virtual circuit where in a data message is tagged with a designated source and destination addresses.

Hub vs Switches

Hub and switches are both used to create ports for one or more devices to another device that provides the internet connection. The difference is that a when a hub receives data, it sends it to all ports. Despite that there are different addresses and destinations, the devices still reads and accepts the incoming data packets from the hub. Therefore disadvantages that occur in hubs are unnecessary traffic within network connections.

On the other hand, switches reads MAC-addresses of the device’s NIC’s that are connected to its ports. A switch reads the destination MAC-address and forwards it to the available ports. If the switch reads the address and not recognizes it, data packet is dropped. Switches reduce network traffic compared to hubs. Traffic that could only occur are broadcast traffic wherein a data packet is sent to all devices connected.

Sources:

http://ecomputernotes.com/computernetworkingnotes/communication-networks/

what-is-routers-explain-types-of-routers

http://www.techspot.com/guides/287-default-router-ip-addresses/

http://home.olemiss.edu/~misbook/comodem.htm

http://searchmobilecomputing.techtarget.com/definition/wireless-router

http://www.wisegeek.com/what-is-a-core-router.htm

http://www.ranker.com/list/the-best-modem-manufacturers/computer-hardware

http://www.ircbeginner.com/ircinfo/Routing_Article.pdf