WEEK 1 IS589 Questions i Week 1 Text Book Questions MIS589: Networking Concepts and Applications DeVry University WEEK 1 IS589 INDIVIDUAL ASSIGNMENT I. Chapter 1 Questions Q7 – The differences have to do with scale (also, geographic scope) and hierarchical relationships. The local area network (LAN) is the most modest and directly accessible to endusers because it is confined to one workgroup, several floors in a building or adjacent buildings. Wired LAN circuits can reach limited distances only. All client PCs on a LAN take turns using the same circuit and the router communicates with other nodes on a backbone network (BN) composed of the nodes/LANS in a sprawling organization occupying, say, a skyscraper or manufacturing complex. BN circuits reach “…hundreds of feet to several miles and provide very high speed data transmission, commonly 100 to 1,000 Mbps” (Fitzgerald & Dennis, 2009, p. 14). BNs access ISP services and circuitry in the same geographic location, hence the third level in the hierarchy comprises metropolitan area networks. Speeds range from 64 Kbps to 10 Gbps over distances up to 30 miles. Access to ISP nodes and thence, to the public data networks/public telephone services networks (PDN/PSTN) of carriers enables LAN and BN routers to communicate with wireless clients, whether in the same city or elsewhere in the world, because the fourth level in the hierarchy is the country-spanning wide-area network. Q. 14 – At the application layer of Internet communications, an outgoing message – clicking on a link or attempting to send an email message – means the browser must create the first of several protocol data units (PDUs) employing an HTTP packet. At the transport layer, the Transmission Control Protocol (TCP) kicks in to access the Internet server and break up the message into smaller TCP packets. When passed on to the third layer, the Network selects the first stop for the message through the network by designating an IP address. If the address is another client in the LAN, the process stops there. But if the request or data transmission must 2 WEEK 1 IS589 INDIVIDUAL ASSIGNMENT 3 access the Internet, the Data Link layer gets imvolved to designate start and stop points, as well as error checksums. Most commonly, this involves an Ethernet PDU. At the final, Physical layer, network cabling transmits the entire assemblage of PDUs as electrical or optical signals. Q17 – Two such standards-making bodies are the Institute of Electrical and Electronics Engineers (IEEE) and the Internet Engineering Task Force (IETF). Membership in the former is evidently limited to those who have passed certification tests for the profession. The IETF, on the other hand, is completely open and voluntary. Anyone interested in shaping the vision and standards for how the Internet should operate is welcome to join. The IEEE-Standards Association focuses on creating or updating standards for LANs.