CS457/557 - MIS420/520 Computer Networks / Networking in a Bus. Env.

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I. Multiple Choice. Please select the best answer and write the letter in the space provided.

_d__ 1. The OSI 7-layer Model

A. is not a standard, nor a collection of standards

B. works as a framework in which standards can be developed,

compared, and understood

C. allows for discussion about the interconnection of two networks

in common terms

D. all of the above

__d_ 2. Which of the following standards making bodies is responsible for Local Area Network standards?

A. ITU B. ISO C. ANSI D. IEEE

_c__ 3. This layer of the OSI model sets up the end-to-end connections.

A. Presentation B. Transport

C. Network D. Physical

_d__ 4. Which of the following is the type of transmission in which each data bit of a byte,when transmitted, travels simultaneously down its own wire?

A. demodulation B. stop bit

C. baud D. parallel

__c_ 5. The data communications equipment which converts digital signals from a PC to analog signals which can then be transmitted over dial-up telephone circuits is called a(n)

A. CO switch B. leased line

C. modem D. RS-232 cable

__b_ 6. Amplitude modulation of a carrier wave is represented by

A. a longer or shorter wavelength

B. an increased or decreased wave height

C. a shift or departure from the normal continuous pattern

D. a square wave

__c_ 7. The number of signaling events per second is called

A. bps B. digital transmission

C. baud rate D. byte

__a_ 8. This type of transmission uses start and stop bits after each character.

A. asynchronous B. synchronous

C. bps D. four-wire

__d_ 9. The process in which two modems initialize themselves and agree to transmit and receive is called

A. turnaround time B. echo cancellation

C. auto negotiation D. handshaking

__c_ 10. Digital data service leased lines are terminated with

A. Modems B. POPs

C. CSU/DSU D. analog data

__c_ 11. This new V series standard will deliver a maximum data rate of 56.6 Kbps over dial-up voice-grade lines.

A. V.42 B. V.34 C. V.90 D. V.56

__c_ 12. Keeping errors from happening in the first place by optimizing the condition of the transmission link is known as

A. error detection B. error correction

C. error prevention D. error protocol deterrence

__d_ 13. The simplest of the error detection techniques is

A. Checksums B. Cyclic Redundancy Checks

C. Longitudinal Redundancy Checks D. Parity

_d__ 14. A privately owned, smaller version of the switched central offices which can control circuit switching for the general public is known as a

A. POP B. CO C. LATA D. PBX

__b_ 15. This technology seeks to integrate the two most common productivity devices, the computer and the telephone.

A. ISDN B. CTI C. PSTN D. PCS

__d_ 16. Which of the following are required to create a LAN?

A. networking software

B. networking hardware

C. shared media physically connecting computers and peripheral

devices

D. all of the above

__a_ 17. Its job is to provide a transparent interface between the shared media of the LAN and the computer into which it is physically installed.

A. NIC B. hub

C. network operating system D. serial port

__d_ 18. A network architecture consists of which of the following?

A. access methodology B. logical topology

C. physical topology D. all of the above

__a_ 19. CSMA/CD is an example of which of the following?

A. access methodology B. logical topology

C. physical topology D. none of the above

__a__ 20. This physical topology is in a linear arrangement with terminators on either end and devices connected to it via connectors and/or transceivers.

A. bus B. ring C. star D. circle

_d__ 21. Which of the following Ethernet media standards gives you the longest maximum segment length?

A. 10Base5 B. 10Base2 C. 10BaseT D. 10BaseF

_b__ 22. This network architecture is a 100Mbps, modified token passing using dual counter-rotating rings.

A. Ethernet B. FDDI C. Token Ring D. IEEE 802.3

_a__ 23. Which of the following NIC media interfaces is used with thin Ethernet?

A. BNC connector B. AUI connector

C. RJ45 connector D. RJ11 connector

_c__ 24. This type of shared-media wiring center is used primarily for Token Ring networks.

A. Repeaters B. Hubs C. MAUs D. AUIs

_a__ 25. This device "cleans up" the digital signals by re-timing and re-generating them before passing the data from one attached device or LAN segment to the next.

A. Repeater B. Hub C. MAU D. Enterprise hub

_d__ 26. Which of the following are concerned with providing an interface between LAN hardware, such as NICs, and the application software installed on a particular client or server?

A. operating systems B. LAN application software

C. LAN productivity software D. network operating systems

_a__ 27. Which of the following would be considered LAN productivity software?

1. Netscape e-mail B. Windows ‘98

C. Windows NT D. McAffee Antivirus

__c_ 28. Software compatibility which is concerned with transparency between similar software layers between different clients and servers is known as

A. vertical software compatibility

B. diagonal software compatibility

C. horizontal software compatibility

D. distributed software compatibility

__b_ 29. This is an emerging service requirement for network operating systems which will allow all network objects to be defined in a single location and shared by all applications.

A. file services B. directory services

C. application services D. printer services

__b_ 30. The suite of communications protocols originally developed by DARPA and used by the Unix operating system.

A. IPX/SPX B. TCP/IP C. NetBIOS D. NetBEUI

II. Matching. Select the word or acronym that best matches the definitions below and write its letter in the space provided.

_L__ 31. __________ are nothing more than rules for how communicating hardware and software components talk to one another.

__H_32. The __________ Model allows data communications technology developers as well as standards developers to talk about the interconnection of two networks or components in common terms without dealing in proprietary vendor jargon.

__M_ 33. Sending data in either direction, but only one direction at a time is known as __________ transmission.

__X_ 34. __________ classes or groups of protocols are defacto standards for error correction and data compression.

__P_ 35. The __________ is an external I/O port which will supply throughputof up to 8Mbps, can daisy-chain up to 127 devices, and can handle data as well as streaming traffic such as voice and video.

__E_ 36. The IEEE 802 committee establishes standards which pertain to the __________ layer of the OSI model.

__D_ 37. In the network layer, data is usually organized into __________ for transmission between networks.

__K_ 38. Full interoperability of NICs depends on compatibility between the

NIC and the network operating system installed in a given computer and is delivered by a software program called a(n) __________.

__N_39. __________ is supported by many high-end LAN switches and allows not only LAN network architectures such as Ethernet, Token Ring and FDDI to be switched extremely quickly but can also switch voice, video, and image traffic as well as interface to WAN services.

__Q_ 40. In a(n) __________ LAN, individual workstations can be configured as a service requester (client), a service provider (server) or a combination of the two.

III. Discussion questions. (Undergraduates – answer two of the following questions; Graduate students must answer all three questions).

41. I have a campusMCI account at home where I use Netscape Communicator to send and receive e-mail. Describe in detail what happens when I connect to my ISP using my V.32bis modem to send an e-mail message from my campusMCI account to my e-mail server (cs.nmhu.edu) at Highlands.

My 14.4 bps modem dials phone and connects to the modem at the ISP.
The two modem negotiate speeds, synchronous/asynchronous, etc. (handshaking).
The two modems convert the signals from their computers from digital to analog (modulate) and vice-versa (demodulate) so that the data can be transmitted across the phone lines.
Once the e-mail message is transmitted from my computer to their mail-server at campus-MCI, it is forwarded through the Internet to our e-mail server (cs.nmhu.edu).

42. Describe the lower three levels of the OSI model model. Be sure to identify protocols, hardware and software associated with these layers as well as any sublayers found in these layers.

43. Describe the following in detail. Use diagrams to aid your discussion.

a) Two different access methodologies.

i)CSMA/CD (Carrier Sense Multiple Access / Collision Detection) - multiple user share a network path allowing only one message to be transmitted at a time

ii) token-passing - token(s) are used to pass messages from computer to computer across the network

b) Two different physical topologies.

i)star (central "node")

ii)bus (shared cable)

iii) ring