Summary

An understanding of the following key points should have been achieved: Understanding bandwidth is essential when studying networking Bandwidth is finite, costs money, and the demand for it increases daily Using analogies like the flow of water and flow of traffic can help explain bandwidth Bandwidth is measured in bits per second, bps, kpbs, Mbps, or Gbps Limitations on bandwidth include type of media used, LAN and WAN technologies, and network equipment Throughput refers to actual measured bandwidth, which is affected by factors that include number of users on network, networking devices, type of data, user’s computer and the server The formula T=S/BW (transfer time = size of file / bandwidth) can be used to calculate data transfer time Comparison of analog and digital bandwidth A layered approach is effective in analyzing problems Network communication is described by layered models The OSI and TCP/IP are the two most important models of network communication The International Organization for Standardization developed the OSI model to address the problems of network incompatibility The seven layers of the OSI are application, presentation, session, transport, network, data link, and physical The four layers of the TCP/IP are application, transport, internet, and network access The TCP/IP application layer is equivalent to the OSI application, presentation, and session layers LANs and WANs developed in response to business and government computing needs Fundamental networking devices are hubs, bridges, switches, and routers The physical topology layouts include the bus, ring, star, extended star, hierarchical, and mesh A WAN consists of two or more LANs spanning a common geographic area A SAN provides enhanced system performance, is scalable, and has disaster tolerance built in A VPN is a private network that is constructed within a public network infrastructure Three main types of VPNs are access, Intranet, and Extranet VPNs Intranets are designed to be available to users who have access privileges to the internal network of an organization Extranets are designed to deliver applications and services that are Intranet based, using extended, secured access to external users or enterprises