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Learn about Ethernet protocol & LAN technology with terms like frames, collision domain, and more. Explore peer-to-peer & client-server networks - advantages, disadvantages, and network architectures. Peer-to-peer vs. client-server for small business.
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Ethernet is the standard communications protocol embedded in software and hardware devices, intended for building a local area network (LAN). • Contention based communication • Two signals at the same time is called a collision • If there is a signal on the wire the computer waits a random amount of time, then tries again Ethernet
Uses Frames to communicate with all devices • Frame must have a source address and a destination address Ethernet
Terms: • Medium - Ethernet devices attach to a common medium that provides a path along which the electronic signals will travel. Historically, this medium has been coaxial copper cable, but today it is more commonly a twisted pair or fibre optic cabling. (UTP) • Segment – Everyone in a LAN that is communicating on the same medium (This room, Library) • Node - Devices that attach to that segment are stations or nodes. • (Computer) • Collision Domain - is a physical network segment where data packets can “collide” Ethernet
Local area network (LAN) technology • It uses a special three-byte frame called a token that travels around the ring. • Token ring frames travel completely around the loop. Token Ring
Communication between service providers (servers) and service requesters, called clients • A server machine is a high-performance host that is running one or more server programs which share its resources with clients • A client does not share any of its resources, but requests a server's content or service function. • Types of Servers: • Print servers • DNS (Domain Name Servers) • File Storage Servers • Database Server • Internet Servers • Application Servers Client Server
All data is stored on the servers, which generally have far greater security controls than most clients • With tens or hundreds of client PC`s, a server is the only way to manage complex and simultaneous operations • Dedicated Server • Servers only job is to server the other computers • Non Dedicated Server • Server is used as a desktop computer for everyday use Client Server
Advantages • High security levels • Login into server • Different levels of access for files and options • Centralized resources • Easy to add computers to network (Scalable) • Easier to upgrade • Disadvantages • More expensive to setup and maintain (increased cost) • If server crashes the network is down • Server software (OS) is more expensive Client Server
Allows for two or more computers to pool their resources together • All clients provide resources, which may include files, printers, storage space • As nodes arrive and demand on the system increases, the total capacity of the system also increases Peer to Peer
Many file sharing networks, including Gnutella, G2 and Limewire. Peer-to-peer file sharing popularized peer-to-peer technologies. As of 2009, it is the largest contributor of network traffic on the Internet. • Best used for small networks under 10 computers • Used where security is not a great concern Peer to Peer
Advantages • No need for network administrator ($45 per hour) • Network is fast / inexpensive to set up • Each PC in the network can back up another PC for security • Easiest type of network to build • As clients increase so does the capacity • Disadvantages • Not centralized making administration difficult • Lack of security • No one computer is reliable • Demand on the network as computers are added • Depended on all computers to function • If one computer is used more often, then that computer becomes slower Peer to Peer