Chapter 1 Questions

WEEK 1 IS589 Questions
Week 1 Text Book Questions
MIS589: Networking Concepts and Applications
DeVry University
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
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.