Application Layer, ITN 100 Exam 1, ITN 100 Study Set Combined
The two functions of middleware are to: 1) provide a standard way of communicating that can translate between software from different vendors, and 2) manage the message transfer between clients and servers so that clients do not need to 'know' which server contains the application's data.
Answer: True
Web-based e-mail like Hotmail is an example of three-tier client-server architecture that provides access to e-mail messages.
Answer: True
SDLC (Synchronous Data Link Control)
Bit-oriented protocol developed by IBM Uses a controlled media access protocol
twisted-pair cable
Cables made of copper wires that are twisted around each other and are surrounded by a plastic jacket (such as traditional home phone wire). Cheapest. Reduce electromagnetic interference Common in telephones
DoD Model
1. Network Access Layer 2. Internet Layer 3. Host-to-Host layer 4. Process Layer
SMTP port
25
TCP/IP Application Layer
5th layer application software that is used by the network user
Fiber Optics Cable
Carries light waves in a glass or plastic Very high bandwidth up to 100s of Gigabits/Sec over long distances 500m to 100km Very secure Expensive to deploy Less expensive in terms of cost per bps
In a client-server network, _________ gets software from different vendors to work together. a. a front-end processor b. serverware c. middleware d. centerware e. programmer
Answer: C
Shielded Twisted Pair (STP)
Copper network cable that has two or four pairs of twisted wires shielded by a braided mesh and covered with an outside coating.
In a two-tier client-server architecture, a client computer needs to use an application layer software package called a ________________ to send e-mail: a. message transfer agent b. router agent c. user agent d. Webcast package e. gateway agent
Answer: C
The acronym, HTML, refers to: a. Header Markup Language b. Hypertext Markup Locator c. Hypertext Markup Language d. Hypertext Markup Library e. Hypertext Modulating Language
Answer: C
Middleware is the software that sits between the application software on the client and the application software on the server.
Answer: True
The four general functions of any application program are: data storage, data access logic, application logic and presentation logic.
Answer: True
Single Mode Fiber
Fiber cables with core diameters of about 7-10 um; light follows a single path (use light in the 1310 nm and 1550 nm range) Uses high-power, highly directional modulated light sources; single-mode fibers are used with lasers.
LAN standards come from
Institute of Electrical and Electronics Engineers(IEEE)
Network layer of OSI is the equivalent of what layer in DOD?
Internet Layer
Analog Data
Voice data
FDM (frequency division multiplexing)
divides horizontally so many signals can travel in one circuit, all signals exist in media at same time but have are on different frequencies so they don't mess with eachother.
Phase of a wave
how much the start of the wave is delayed or advanced (in time)
Frequency of a wave
number of complete waves that pass a point per second
Crosstalk
occurs when the signals of one wire affect the signals on an adjacent wire
Thick Client
processing is split between server and client
There are required and optional parts of an HTTP response. They are:
response status, response header, response body
Define Bandwidth
the amount of data that can be transmitted in a certain amount of time.
Cloud Computing
the practice of using a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer.
What is not a general function by any application program?
application access storage
Application Layer Protocols
(1.) Utility (DNS, SNMP, DHCP (2.) Messaging protocols (SMTP) (3.) Data Transfer protocols (NFS, FTP) (4.) Interactive protocols (Telnet)
HDLC (High-level Data Link Control)
A bit-oriented synchronous data link layer protocol developed by the International Organization for Standardization (ISO).
NFS (Network File System)
A client/ server application that enables users to access shared files stored on different types of computers and work with those files as if they were stored locally on their own computers. port 2049
distributed computing
A form of computing where systems in different locations communicate and collaborate to complete a task. Client server is this
centralized computing
A model where all computing for a network is done by a large central device. A mainframe
TDM (time division multiplexing)
A multiplexing method in which the communication channel is divided into discrete time slots that are assigned to each node on a network.
DWDM (Dense Wavelength Division Multiplexing)
A multiplexing technique used over single-mode or multimode fiber-optic cable in which each signal is assigned a different wavelength for its carrier wave.
Client -Server Architecture
A network design in which client computers use a centrally administered server to share data, data storage space, and devices.
DHCP (Dynamic Host Configuration Protocol)
A network service that provides automatic assignment of IP addresses and other TCP /IP configuration information. UDP 67, 68
Point-to-Point Protocol (PPP)
A protocol that allows a computer to connect to the Internet over a phone line. Common WAN protocol.
FTP (File Transfer Protocol)
A protocol used to move files and folders over a network or the Internet. Port 20 and 21
What is a protocol?
A set of rules for how devices communicate and how data is transmitted across a network
Access method
A set of rules used by LAN hardware to direct traffic on the network. It determines which host or device uses the LAN next.
Multimode Fiber
A type of fiber optic cable that carries multiple light signals on a single strand.
STDM (statistical time division multiplexing)
A type of multiplexing that assigns time slots to nodes (similar to TDM), but then adjusts these slots according to priority and need using statistical network data.
There are required and optional parts of an HTTP response. They are:
All three parts (request line, request header, request body) of a request from a web browser to a web server are required when a request is made. A request header for an ____ request starts with a command, such as GET, and ends with the ______ version number that the browser understands.
An N-tiered architecture: a. is generally more "scalable" than a three-tiered architecture b. is generally less "scalable" than a three-tiered architecture c. uses only two sets of computers in which the clients are responsible for the application and presentation logic, and the servers are responsible for the data d. uses exactly three sets of computers in which the client is responsible for presentation, one set of servers is responsible for data access logic and data storage, and application logic is spread across two or more different sets of servers e. puts less load on a network than a two-tiered architecture because there tends to be less communication among the servers
Answer: A
In the three tier architecture the software on the client computer is responsible for____________. a. presentation logic b. application logic c. data access logic d. data storage e. application storage
Answer: A
There are required and optional parts of an HTTP response. They are: a. response status, response header, response body b. response address, response header, response body c. response status, response body d. response address, response header e. response status, response header
Answer: A
To interact with the World Wide Web, a client computer needs an application layer software package called a: a. Web browser b. Web server c. Telnet package d. Uniform Resource Locator package e. Router package
Answer: A
_________ is an application program function that deals with storing and retrieving data. a. data storage b. data access logic c. application logic d. presentation logic e. application access storage
Answer: A
A(n) _________-tiered architecture uses only two sets of computers: one set of clients and one set of servers. a. one b. two c. three d. five e. n
Answer: B
An application program function is __________, or the processing required to access data. a. data storage b. data access logic c. application logic d. presentation logic e. application access storage
Answer: B
Marc Andreessen led a team that developed the first graphical Web browser, which was called: a. Internet Explorer b. Mosaic c. Firebird d. Netscape Navigator e. Mozilla
Answer: B
One underlying problem with a host-based network is that: a. there are economies of scale because all computer resources are centralized b. the server can get overloaded since it must process all messages c. the architecture is relatively simple and works well d. the server is the one point of control which simplifies security e. clients (terminals) do not require sophisticated hardware/software because they do not perform most of the work in this type of architecture
Answer: B
The idea for a special hypertext network, called the World Wide Web, was conceived of by: a. Microsoft in 1994 as part of the Windows 95 project b. Tim Berners-Lee at the European Laboratory for Particle Physics (CERN) in 1989 c. Vinton Cerf, for the U.S. Department of Defense in 1969 as a network of four computers called ARPANET d. Howard Flieshman of IBM in 1982 as part of the development of the IBM PC e. the University of Minnesota as an extension of Gopher
Answer: B
With the "thin client" architecture, when an application changes, only the _________ with the application logic needs to be updated. a. client b. server c. middleware d. hardware e. software
Answer: B
With the two-tier client-server architecture, the client is responsible for the ________ logic and the server is responsible for the ________ logic. a. Application; presentation b. Presentation; data access c. Data access; presentation d. Application; data access e. Presentation; application storage
Answer: B
A "thick client" architecture approach: a. always is a two-tier network architecture b. always is an n-tiered architecture c. places all or almost all of the application logic on the client d. places all or almost all of the application logic on the server e. refers to the size of the cable connecting the clients to the network
Answer: C
Client-server architectures: a. cannot connect computers that use different hardware b. are one of the least used network architectures today c. can use middleware to provide a standard way of communicating between software from more than one vendor d. assign the responsibility for the presentation logic to the server e. were the earliest type of network architectures
Answer: C
Each server on a network that needs to act as a web server needs an application layer software package called a (n) ______________. a. browser b. application web c. web server d. operating system e. none of the above
Answer: C
How are the application architecture functions split up in a client-server network? a. the presentation logic and data storage are on the client, while the data access logic is on the server b. the data storage, data access, and presentation logic are on the client c. the presentation logic is on the client, while the data storage and data access logic are on the server d. the data storage and data access logic are on the client, while the presentation logic are on the server e. the presentation logic and data access logic are on the client, and the data storage is on the server
Answer: C
With respect to costs for a client-server network, which of the following is true? a. Personal computers used as clients in a client-server network cost about the same as mainframes for the same amount of computing power. b. More network capacity, which costs more money, is required for client-server networks than for client-based networks. c. Experts believe that client server architectures can be complex, but that developing application software for host based architectures is usually cheaper. d. Updating the network with new version of software tends to be less expensive in a client-server network since the software is centralized in one client. e. None of the above
Answer: C
______________, or the algorithms or business logic programmed into the application, can be simple or complex depending on the application. a. data storage b. data access logic c. application logic d. presentation logic e. application access storage
Answer: C
A "thin client" architecture approach: a. always is a two-tier network architecture b. always is an n-tiered architecture c. places all or almost all of the application logic on the client d. places all or almost all of the application logic on the server e. refers to the size of the cable connecting the clients to the network
Answer: D
A(n) __________ is the way in which the functions of the application layer software are spread among the clients and servers in the network. a. anonymous FTP b. data access logic c. fat client d. application architecture e. response status architecture
Answer: D
One disadvantage of the ____________ architecture is that places a greater load on the network. a. two-tier b. three tier c. one-tier d. n-tier e. layered
Answer: D
To get a page from the Web, a user must type in a URL, which stands for: a. Unknown Resource Locator b. Unknown Router Location c. Uniform Router Location d. Uniform Resource Locator e. Uniform Resource Library
Answer: D
With a client-based network, one fundamental problem is that: a. the clients each must store all the data b. the server does not have any data storage capability c. the host or server must perform presentation logic, application logic, and data access logic at the same time d. all data on the server must travel to the client for processing e. the clients must perform the data storage logic
Answer: D
________ is the presentation of information to the user and the acceptance of the user's commands. a. data storage b. data access logic c. application logic d. presentation logic e. application access storage
Answer: D
IMAP (Internet Message Access Protocol): a. is a set of standards that define how email is to be processed between mail servers b. is exactly the same as SMTP c. copies an e-mail message from the client computer's hard disk, deletes it from the client, and stores it on the mail server d. is exactly the same as POP e. permits an e-mail message to remain stored on the mail server even after they have been read by a client computer
Answer: E
There are optional and required parts of an HTTP request. They are: a. request address, request body b. request address, request header, request body c. request line, request header d. request line, request body e. request line, request header, request body
Answer: E
Which of the following is not a general function by any application program? a. data storage b. data access logic c. application logic d. presentation logic e. application access storage
Answer: E
A "thin client" approach places most of the application logic on the client.
Answer: False
A request header for an HTTP request starts with a command, such as GET, and ends with the HTTP version number that the browser understands.
Answer: False
All three parts (request line, request header, request body) of an HTTP request from a web browser to a web server are required when a request is made.
Answer: False
An application architecture is the way in which the functions of the application layer are performed solely by the clients in the network.
Answer: False
As the demand for more and more network applications grow; host-based computing becomes the best solution.
Answer: False
Host-based and client-based networks are similar in that the client computer performs most of the work.
Answer: False
One major drawback to a client-server network lies in the fact that client-server networks enable software and hardware from different vendors to be used together.
Answer: False
The Simple Mail Transfer Protocol is the least commonly used e-mail standard.
Answer: False
The World Wide Web was conceived at University of Utah as part of the development of the Internet.
Answer: False
The application architecture called the distributed computing model uses the "thick" client approach.
Answer: False
The earliest data communications networks were client-server networks.
Answer: False
The two-tier e-mail architecture does not require any application software on the client computer.
Answer: False
To use the Web, each client computer requires a data link layer software package called a Web browser.
Answer: False
Using the POP standard for client to server e-mail communication, the e-mail messages remain on the server computer.
Answer: False
A network computer is designed primarily to communicate using Internet based standards, but has no hard disk. It has only limited functionality.
Answer: True
In a client-server network, the presentation logic is the responsibility of the client computer.
Answer: True
In the three-tier architecture, the software on the client computer is responsible for the presentation logic, an application server is responsible for the application logic and a separate database server is responsible for the data access logic and data storage.
Answer: True
HDLC vs SDLC
Difference between the two is SDLC is synchronized by a clock or something, while HDLC is not
The representation of the character A by the group of 8 bits, 01000001, is an example of:
Digital Coding
Throughput
Energy that is integrated into the system so it can be used by the system to accomplish its goals. Depends on retransmission rate, transmission rate, and delay.
Cyclic Redundancy Check (CRC)
Error Checking function, did the 1's and 0's arrive in tact
TCP/IP Data Link Layer
Formats the message to indicate where it starts and ends, decides when to send it to physical media, and finds and fixes errors.
The ability to transmit in both directions, but only in one direction at a time is an example of _______________ transmission.
Half Duplex
Coax Cable
Has a single copper core, plus outer insulation, shielding, and inner insulation Less prone to interference Characteristics Price - inexpensive (but more costly than TP) Distance - up to 2 km (1.2 miles) Use: Cable TV / Internet
amplitude of a wave
Height of a wave
Transport layer of OSI is the equivalent of what layer in DOD?
Host to Host Layer
HTTP and HTTPS
Hypertext Transfer Protocol. A protocol for controlling how Web browsers and servers pass information back and forth over the Internet. HTTPS uses encryption.
Wifi Standards
IEEE 802.11
LAN Standards
IEEE 802.3
Default Gateway
In a TCP/IP network, the nearest router to a particular host. This router's IP address is part of the necessary TCP/IP configuration for communicating with multiple networks using IP.
Physical Layer
Layer 1 physical connection between the sender and receiver. In both the OSI and Internet Model. Data is physically transmitted from one computer or terminal to another in the ________ layer.
OSI Model: Data Link
Layer 2 Formats message to indicate where it starts and ends, decides when to transmit, detects and fixes errors.
OSI Model:Network Layer
Layer 3 Provides mechanisms for the routing of data between devices across single or multiple network segments. Handles the discovery of destination systems and addressing.
TCP/IP Network Layer
Layer 3 responsible for creating, maintaining, and ending network connections. Uses the Internet Protocol to transfer data within and between networks
TCP/IP Transport Layer
Layer 4 Establishes, maintains, and breaks connections between two devices.
OSI Model:Transport Layer
Layer 4 Establishes, maintains, and breaks connections between two devices. Performs error checking and verification and handles retransmissions if necessary.
OSI Model:Session Layer
Layer 5 Responsible for maintaining logical sessions between computers
OSI Model: Presentation Layer
Layer 6 Formats data for presentation to the user by accomodating to different interfaces
OSI Model: Application layer
Layer 7 responsible for interfacing with the user; HTTP, FTP, SMTP
Thin Client
Most processing is done on the server or database;
Unshielded Twisted Pair (UTP)
Networking cable that has four twisted pairs of copper wire and a flexible outer coating.
Application Layer preforms the tasks of what other layers in Internet Model?
application,presentation,session
A(n) __________ circuit is another name for a multipoint configuration.
Shared
CSMA/CA
Short for carrier sense multiple access with collision avoidance. It is used as a method for multiple hosts to communicate on a wireless network and AppleTalk.
CSMA/CD
Short for carrier sense multiple access with collision detection. It is the method for multiple hosts to communicate on a Ethernet.
Telnet (Telecommunication Network)
TCP 23 Remote console login to network devices
Simple Mail Transfer Protocol (SMTP)
The Internet standard protocol for transferring e-mail messages from one computer to another.
TCP/IP
The dominant set of protocols for the transfer of data over the Internet.
Internet Protocol (IP)
The network protocol that deals with the routing of packets through interconnected networks to the final destination
404 Error
The page is broken, or doesn't exist. It's usually due to someone reaching a page that has been deleted or they mistyped the URL.
Network Interface preforms the tasks of what other layers in Internet Model?
The physical and data link layers
DNS (Domain Name System)
The service that translates URLs to IP addresses. Port 53
OSI Model
The seven layers describing network functions
Why do we have networking standards?
To make sure that the hardware and software that is made by different vendors can work together seamlessly.
Bandwidth is the difference between the highest and lowest frequencies in a band.
True
Statistical time division multiplexing does not require the capacity of the circuit to be equal to the sum of the combined circuits.
True
Microwave
Wireless transmission,not the same as wifi,Line of sight required if somethings in the way it won't work. Point to Point high speed.
WWW
World Wide Web; a system of interlinked hypertext documents contained on the Internet
WDM (wavelength division multiplexing)
____ is a technology used with fiber-optic cable, which enables one fiber-optic connection to carry multiple light signals simultaneously.
Dispersion
___________ refers to the spreading of the signal that different parts of the signal arrive at different times at the destination.
Ethernet
a system for connecting a number of computer systems to form a local area network, with protocols to control the passing of information and to avoid simultaneous transmission by two or more systems.
Digital Data
binary, on and off, 0 or 1,produces fewer errors since its binary. more secure
Modem (Modulator-Demodulator)
convert digital data to analog signals and vice versa
Codec
converts analog data into a digital signal.
Bits
the smallest unit of data the computer can process