VIEWS: 0 PAGES: 12 POSTED ON: 7/16/2013
Introduction To Computer Systems 9. Network Connectivity 1. Introduction A network is any collection of independent computers that communicate with one another over a shared network medium. Every network includes: •At least two computers Server or Client workstation. •Networking Interface Card's (NIC) •Connection medium, usually a wire or cable, although wireless communication is also possible. •Network Operating system (NOS) software, such as Microsoft Windows NT or 2000, Novell NetWare, Unix and Linux. 2. Types of Networks - LAN LANs (Local Area Networks) A network is any collection of independent computers that communicate with one another over a shared network medium. LANs are networks usually confined to a geographic area, such as a single building or a college campus. LANs can be small, linking as few as three computers, but often link hundreds of computers used by thousands of people. 3. Types of Networks - WAN WANs (Wide Area Networks) Wide area networking combines multiple LANs that are geographically separate. This is accomplished by connecting the different LANs using services such as dedicated leased phone lines, dial-up phone lines (satellite links, and data packet carrier services. Wide area networking can be as simple as a modem and remote access server for employees to dial into, or it can be as complex as hundreds of branch offices globally linked. 4. Categories of Networks Networks can be divided into 2 main categories: •Peer-to-Peer Peer-to-peer •Server Based In peer-to-peer networking there are no dedicated servers or hierarchy among the computers. All of the computers are equal and therefore known as peers. Normally each computer serves as Client/Server and there is no one assigned to be an administrator responsible for the entire network. 4. Categories of Networks cont… Client/Server Model The term Client/server refers to the concept of sharing the work involved in processing data between the client computer and the most powerful server computer. The Client/server network is the most efficient way to: •Databases and management of applications such as Spreadsheets, Accounting, Communications and Document management. •Network management. •Centralized file storage. 5. Wired Connections In the network you will commonly find three types of cables used these are: •Thin / Thick coaxial cable •Twisted Pair Cable • STP (Shielded Twisted Pair) • UTP (Unshielded Twisted Pair) •Ethernet Cabling •Fiber Optic Cable 5. Wired Connections cont… The most common type of cable used is the Twisted Pair (STP). Is more common in high-speed networks. The biggest difference you will see in the UTP and STP is that the STP use's metallic shield wrapping to protect the wire from interference. The bigger the number the better the protection from interference. Most networks should go with no less than a CAT 3 and CAT 5 is most recommended. 6. Wireless Connections Wireless connections transfer data without the use of cables or wires. Generally, warless connections are not as fast or as reliable as cables but they can be convenient. They are very popular technology for small networks because computers, especially laptops, can be moved around while remaining connected to the network. 6. Wireless Connections cont… Wireless networks normally use radio transmissions which can include: • Wi-Fi Wireless radio technology that can be used to send data between devices and computers. You can build a small network in a home or office using Wi-Fi instead of cables. Most mobile phones can use Wi-Fi technology to access the internet. 6. Wireless Connections cont… 2. Bluetooth Similar to Wi-Fi but only works over short distances and is slower. It is mainly used to send data between two devices such as a mobile phone and headset, or between a digital camera and laptop. 6. Wireless Connections cont… Wireless networks normally use radio transmissions which can include: 3. 3G Another radio technology that is used by mobile phone networks. It can carry more data than the older mobile phone systems.
Pages to are hidden for
"Types of Microcomputers"Please download to view full document