If computer networks are working well, we have a tendency to hope to have is usually the inner workings of the modules of the system is evident that the typical user. The most common parts of a network of laptop, not counting the cables are “router”, “hubs” and “switch”. Many of these modules may be similar cosmetically. Each session is usually Ethernet port (RJ45 connector, which looks like an oversized phone phone) and LED displays. However, these modules work differently, and it is important to understand the differences.

network of modern equipment operates on the Open System Interconnection (OSI) standard. This practice is defined as the communication should be conducted in a network. In complying with this standard modules from different manufacturers will co-exist on the same network. Wireless networks (WLAN) and then use 802.11X are a subset of the control systems network.

When a message is sent from a computer, it is broken into several parts. On the lower level, the message to “1″ and “zero” bit is reduced. The next stage, a group of bits as a “framework”. A frame contains the information management and the destination address, and error detection. The next step could be a group of executives as a “package”. The framework for the procedures and packages are sometimes used interchangeably. If a message is sent through a complex network like the Internet, may take a number of packets a different way, and are brought together at your destination.

error detection is used with each part and parcel. The place common routine is called, “Cyclic Redundancy Check (CRC). Sums CRC of all” a “s in the frame or packet. This species is stored as hex-head price of the frame / packet. Repeated Upon arrival reception, the operation . If I have the two hexadecimal values, take a look at the pass Otherwise, calls the receiving device that the device is sending back. Most of this function is performed by integrated circuits (chips) into the network modules.

The Hub The Hub network is on the first layer of the OSI standard, known as the work “Physical Layer”. The hub is the simplest of the three modules. A hub is not awake to be treated the message content, they treat the message as bits. It’s just records the signal and repeat all or part, with return to port, which sent the message. An “active” hub allows you to noise, the electrical signal clean and amplify the signal before transmission. not receive a step up “passive hub, the signal it receives is simply a symptom, and sends the signal received at each port. The hubs are typically used to connect multiple computers to a printer.



The network switch works on the second layer of the OSI banality known as the Information link “layer.” The network switch, as the name implies, means of signaling switch so that a message is sent to a selected target. A switch can improve the performance of networks, particularly in networks with multiple computers. A switch has enough intelligence on board on the way to any destination to remember. The switch has a network of message images.

After you save the connect a PC to a network switch, the switch, the Media Access Management, or “MAC” address of the PC Card Network Interface Card (NIC). This is often called IP address or ARP. “When a frame is received is selected for a supposed PC, the switch is the only framework for the computer sends. By preventing network methods that are used by each frame, the network resources are protected. A laptop is a framework to Send PC B, while at the same time, PC C sends a frame to computer D

The Router network works on the third layer of the OSI standard, the so-called network layer. “The name of a router is also an indicator of their role. Routers have some of the same skills, such as switches, routers, however, are the most commonly used to attach two or a large number of networks. For example, a router, you can be a wireless network with a typical local area network (LAN). Another common use is to be attached to a LAN to the Web (a “WAN” or “WAN”). In this capacity, the router uses Network Address Translation (NAT), so that each computer connected to the LAN to share an IP address. A router the message into packets. A router uses addresses in IP packets for routing between multiple networks.

A PC is configured to manage the operation of a router if it has a software router and 2 or more than one network interface card (NIC). A separate card is required for each network.

A router is capable of advanced features such as Protocol (DHCP domain management host) server and firewall. A firewall protects the computer from the dangers of computers as opposed to outside the network. Connect networks usually require multiple protocol conversion.

A router is a ranking varied. Router might connectivity in the office, quite different between sites and between companies and the Internet. largest service providers to offer net routers are in very large networks, companies, or close a company with a satellite link to a place of foreign companies. Advanced routers are powerful computers with microprocessors. Terribly sophisticated routers are used by the Web to manage network traffic more efficiently.

A router maintains a table as “monitors Routing Information Base (RIB) that contains information about the routes known. The RIB will be static (determined manually by a network administrator) or dynamic (frequently updated based mainly on conditions). A RIB is a simple little over a LAN will be very very heavily used routers on the Internet difficult.

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There are many other varieties of network modules that the three mentioned here, and considerable duplication of work roles. For example, an intelligent hub can “many properties have a network switch. Wireless networks (WANs) have has much in common with their cousins-LAN standard, but the Additional Protocol to the special security and interference problems specific to wireless networks. The multiple roles can be combined in one package. Network routers have subsets, as network switches function.


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