COMM 226 Networks and collaboration Chitu Okoli Associate Professor in Business Technology Management John Molson School of Business, Concordia University, Montréal 1

Major Network Types Local Area Network (LAN) –Network in premises 100% owned by one organization –No need to ask the city or anyone else for special permits for laying cables Wide Area Network (WAN) –Spans spaces not fully controlled by the organization (e.g. neighborhood, city, country) –Requires public network services –Crosses city streets Internet –International network of interconnected networks –Owned by no one; shared by everyone

Local Area Network (LAN)

Major kinds of network cables Unshielded twisted pair (UTP) cable –Used for small LANs –Conducts electricity using copper cables –Similar to a telephone cable, but thicker –Maximum speed: 10 gigabits per second (1.25 GB/s) Fibre optic cable –Used for larger LANs and for WANs –Conducts light (lasers) within glass or plastic fibres –This is what Bell’s Fibe service uses –Maximum speed: unknown Current record is around 255 terabits per second (31,800 GB/s) Source:

Comparative network transmission speeds

Local Area Network with Wireless

Basic Internet connection

URLs and domain names Uniform Resource Locator (URL) –easy to remember address on the Internet Domain name –Unique name to identify a node on the Internet –Corresponds to an IP address ( ) –Domain Name Service (DNS) maps domain names to their corresponding IP address Like how a phone book maps people’s names to their corresponding phone numbers –Contains sub-domains, separated by periods third-level domain (optional) filename of HTML document second-level domain (acquired by organizations or individuals) top-level domain (assigned by ICANN) Indicates that this is a webpage (hypertext transfer protocol) html or htm extension (optional)

Common top level domains (TLDs) DomainDescription com, net, org, infoAnyone, anywhere eduHigher education govUnited States Government milUnited States Military ca, uk, us, mx, fr Country indicators tv, fm, co, md, cc, wsCountry indicators with special marketing biz, name, care, etc.Newer TLDs with particular meanings 9

Virtual Private Network (VPN)

Virtual Private Network (VPN) Private network: like your home network or enterprise network—it is private, not public like the Internet VPN uses the Internet to create a special connection with the security and privacy of private network (hence, a “virtual” private network) VPN advantages: –Secure, encrypted connection (harder to hack or spy) –Access to special resources normally available only to the private network VPN disadvantages: –Slower connection because of encryption –Sometimes somewhat complicated to set up Concordia provides free VPN

Sources Most of the slides are adapted from COMM 226 Business Technology Management by David M. Kroenke, Andrew Gemino, Peter Tingling, and Earl H. McKinney, Jr. 2nd Custom Edition for Concordia University (2014) published by Pearson Canada. ISBN 13: Other sources are noted on the slides themselves 12