- What do you know about network?
- What is the difference between LAN and WLAN?
- What is WLAN?
- What do you know about server and client?
Computer Networking is basically the process of connecting two or more computers or devices, using hardware and software, so that data can be transferred and shared between them.
There are different types of networking, for instance there are LANs (local area networks) and WANs (wide area networks). The difference between these two lies in their spans. LANs are restricted to small areas, typically homes, whereas WANs are widely spread and can reach across cities, countries or even continents.
Networks may also be different in their design and layout. There are client/server networks and peer-to-peer networks. Client/server networks tend to be centralized with most functions being supported by the central/main system. Peer-to-peer networks consist of computers which all support the same functions and can interact with each other.
This being understood, client/server networks work well within businesses whereas peer-to-peer is better suited to home use.
Layouts can be the different ways in which a network is arranged to share data. Bus, ring, star, mesh is all different layouts. It all depends on how information is to travel through the network, if the data is expected to go through all the systems then bus network is suitable but if data is to be sent to single units separately then star networks or mesh networks might be better suited.
Networks are all about communication, as such there is a communication standard which is implemented by protocols, which are like rules for the operation of the network. There may be many protocols used by a network at one time, for instance, TCP/IP, the most common protocol found on the Internet and in home networks.
Networks can be wired or wireless. Most protocols for wired networks are also supported by wireless networks. Wired networks have been around for a long time as compared to wireless ones. But with advancements in technology wireless networks are fast becoming more reliable and common.
LAN stands for Local Area Network, which is a collection of computers and other network devices in a certain location that are connected together by switches and/or routers that facilitate the communication of the network elements. Each computer or network element is connected to the switches/routers via a UTP cable. The added letter in WLAN stands for wireless. This is a type of network where the data is not transmitted via cables but over the air through the use of wireless transmitters and receivers.
WLANs are deployed in areas where a wide number of computers may connect to the network but not at the same time. Places like coffee shops often add WLAN to their shops to entice more customers who do not stay for extended periods. Even at home where you have a somewhat fixed number of computers that connect to the network, WLAN is also preferred as it gives users the freedom to move around the house and carry their laptops with them without needing to fuss with cables. For areas where the computers are pretty much fixed, a wired LAN is very desirable due to the advantages that it offers.
First off, a wired LAN is much faster compared to a WLAN. Most wireless routers nowadays are limited to a theoretical maximum speed of 54mbps while a contemporary wired LAN has a bandwidth of 100mbps. Gigabit network equipment can even ramp this up to 1000mbps or 1Gbps. This might not be such a big issue for browsing the internet or sending email but when you are copying large files, it can take a while with a WLAN.
WLANs are also vulnerable to attack as just about anyone with a strong enough transceiver is able to detect the signal. Access can then be achieved by breaking the encryption used by the router through certain software. The information that is being transmitted through the WLAN can also be collected by malicious person and used in a variety, often destructive, ways. In order to intercept data in a wired LAN, you need to physically connect to a switch or a router.
Summary:
· LAN refers to a wired network while WLAN is used to refer to a wireless network.
· LAN is commonly used in fixed networks while WLAN is common in areas where computers are moved quite often.
· WLAN is more convenient to users compared to LAN.
· LAN is much faster compared to WLAN.
· LAN is more secure compared to WLAN
A wireless local area network (WLAN) is a local area network (LAN) that doesn't rely on wired Ethernet connections. A WLAN can be either an extension to a current wired network or an alternative to it.
WLANs have data transfer speeds ranging from 1 to 54Mbps, with some manufacturers offering proprietary 108Mbps solutions. The 802.11n standard can reach 300 to 600Mbps.
Because the wireless signal is broadcast so everybody nearby can share it, several security precautions are necessary to ensure only authorized users can access your WLAN.
A WLAN signal can be broadcast to cover an area ranging in size from a small office to a large campus. Most commonly, a WLAN access point provides access within a radius of 65 to 300 feet.
WLAN types :
Private home or small business WLAN
Commonly, a home or business WLAN employs one or two access points to broadcast a signal around a 100- to 200-foot radius. You can find equipment for installing a home WLAN in many retail stores.
With few exceptions, hardware in this category subscribes to the 802.11a, b, or g standards (also known as Wi-Fi); some home and office WLANs now adhere to the new 802.11n standard. Also, because of security concerns, many home and office WLANs adhere to the Wi-Fi Protected Access 2 (WPA2) standard.
Enterprise class WLAN
An enterprise class WLAN employs a large number of individual access points to broadcast the signal to a wide area. The access points have more features than home or small office WLAN equipment, such as better security, authentication, remote management, and tools to help integrate with existing networks. These access points have a larger coverage area than home or small office equipment, and are designed to work together to cover a much larger area. This equipment can adhere to the 802.11a, b, g, or n standard, or to security-refining standards, such as 802.1x and WPA2.
Client/server describes the relationship between two computer programs in which one program, the client, makes a service request from another program, the server, which fulfills the request. Although the client/server idea can be used by programs within a single computer, it is a more important idea in a network. In a network, the client/server model provides a convenient way to interconnect programs that are distributed efficiently across different locations. Computer transactions using the client/server model are very common. For example, to check your bank account from your computer, a client program in your computer forwards your request to a server program at the bank. That program may in turn forward the request to its own client program that sends a request to a database server at another bank computer to retrieve your account balance. The balance is returned back to the bank data client, which in turn serves it back to the client in your personal computer, which displays the information for you.
The client/server model has become one of the central ideas of network computing. Most business applications being written today use the client/server model. So does the Internet's main program, TCP/IP. In marketing, the term has been used to distinguish distributed computing by smaller dispersed computers from the "monolithic" centralized computing of mainframe computers. But this distinction has largely disappeared as mainframes and their applications have also turned to the client/server model and become part of network computing.
In the usual client/server model, one server, sometimes called a daemon, is activated and awaits client requests. Typically, multiple client programs share the services of a common server program. Both client programs and server programs are often part of a larger program or application. Relative to the Internet, your Web browser is a client program that requests services (the sending of Web pages or files) from a Web server (which technically is called a Hypertext Transport Protocol or HTTP server) in another computer somewhere on the Internet. Similarly, your computer with TCP/IP installed allows you to make client requests for files from File Transfer Protocol (FTP) servers in other computers on the Internet.
Other program relationship models included master/slave, with one program being in charge of all other programs, and peer-to-peer, with either of two programs able to initiate a transaction.
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