Introduction to computer science Final
Terms in this set (92)
used to express algorithms
Issues with using natural language to represent algorithms
• Natural language can be extremely verbose
• Lack of structure makes it difficult to locate specific sections of the algorithm
• Natural language is too "rich" in interpretation and meaning
Continuation condition is tested at the beginning of each pass through the loop
Continuation condition is tested at the end of the loop body, not the beginning
Instructions that computing agent understands and is capable of executing without further explanation
Constant run time
Logarithmic run time
Linear run time
Linearithmic run time
Quadratic run time
For a sequence of instructions, the cost of executing the sequence of instructions is, asymptotically speaking, the same as the maximum cost of the individual instructions.
Foraconditionalstatement,thecostofexecutionis the maximum of the cost of evaluating the condition and the cost(s) of the alternate instruction sequences
Applies to an iterative construct (e.g., loop, for, while) that will cause the execution of a subset of instructions to be repeated a specified number of times.
is a set of independent computer systems connected by telecommunication links for the purpose of sharing information and resources.
1. Wireless local area network (WLAN)
a user transmits from his or her computer to a wireless router. The router is then connected to a traditional wired network that provided full Internet access. (Wi-Fi, Bluetooth
2. Wireless wide area network (WWAN)-
the computer transmits messages to a remote base station provided by the telecommunications company. (4G cell phone usage) it offers services as well as data communication
1. Local area network (LAN)
connects hardware devices such as computers, printers, and storage devices that are all in close proximity to each other.
2. Wide area network (WAN)
connects devices that are not in close proximity but rather are across town, across the country, or across the ocean. These are dedicated point-to-point lines or wireless links that directly connect two machines.
is a general term applied to any use of computers and networking to support the paperless exchange of goods, information, and services.
is an automatic repeat request if the data that is received is corrupted.
Which of the following layers deals with rules for implementing the end-user services provided by a network?
Which of the following layers deals with error handling and framing?
Data Link Layer
Which of the following is a low power wireless standard used to communicate between devices located close to each other?
Which of the following best characterizes the statements:
A) Networks can be used to share resources like printers and storage
B) Routers are used to connect networks
Both A and B are True
Which of the following best characterizes the statements:
A) The ARQ algorithm includes a provision for what to do if a packet is not received.
B) A DNS server is used to register domain names
Only A is True
is the process of verifying that you really are the person who has the right to access this computer.
this form of encryption is easy to apply but hard to undo. The hash function takes the password the user originally chooses chops it up, and stirs it around according to the formula.
will first try all words in its built in dictionary, encrypting each with the well-known hash function.
is the process of using people to get the information you want. (ex. Sending emails pretending to be someone your not)
(ex. Pretending to be the bank but you're actually a hacker)
governs what an authentic user is allowed to do on the machine or in a network.
Has access to everything
is similar to a virus but it can send copies of itself to other nodes on a computer network without having to be carried by an infected host file. It is self replicating and can travel from node to node without any human intervention.
is a computer program that does some harmless job, but unbeknownst to the user the code contains a virus.
captures the users passwords and credit card numbers and sends them to someone else
Denial of Service-
is typically directed towards a business or government site. The attack routs everyone to a single URL at roughly the same time. This effectively shuts down the legitimate users.
is a practice used to illegally obtain information without hacking. An e-mail is sent claiming to be from a legitimate organization, and asks for sensitive information. (ex. Fake bank email)
is the science if "secret writing" a message in plane text is encoded before it is sent, for the purpose of keeping its context secret.
is the process of using an algorithm to convert information into something that cannot be understood.
is the reverse, and is using an algorithm that converts the encryption back into plain text.
Symmetric encryption algorithm-
requires the use of a secret key known by both the sender and the receiver.
Asymmetric encryption algorithm-
also called public key encryption. The key for encryption and the key for decryption are different. Person A can make an encryption key public and anyone can encrypt a message using A's encryption algorithm. But only A has the key to decrypt it.
involves shifting each character in the message to another character some fixed distance away
a group of block of plaintext letters gets encoded into a block of ciphertext
DES- (Data encryption Standard)
is an encryption algorithm developed by IBM in the 1970s for the U.S. National Bureau of Standards.
AES- (Advanced encryption Standard)
was created after advancements in technology meant that super computers could eventually break DES with brute force.
are computational devices such as chips, processors, or computers that are embedded within another system. Unlike a general purpose computer they usually have just one or two tasks that they complete. (TV remote)(in your credit card)(in ipod or MP3 player).
A keystroke logger is an example of a:
The science of secret writing is:
Which of the following terms does not belong with the others?
The encryption algorithm that TLS/SSL uses is:
Both DES and RSA
Embedded computers can be found:
In a cell phone, in a credit card, in a microwave
A computing agent must do all of the following
1. Accept input
2. Store information and retrieve it from memory
3. Take actions according to algorithm instructions.
4. Produce output.
includes a conceptual tape that extends infinitely in bot directions. The tape is divided into two cells, each of which contains one symbol. *
always contains a special symbol b for blank
The Turing machine does capture the properties we identify as essential for a computing agent.
Which of the following best describes the statements:
A. The model of a phenomenon must capture the full functionality of the real thing.
B. Models can only give us information about existing phenomena.
Only B is true
Which of the following best characterizes the two statements:
A. The Turing machine captures all of the properties that are essential for a computing agent.
B. A Turing machine can store information and retrieve it from memory.
both A and B are true
A Turing machine always contains a special symbol for:
Characterize the following statements:
A) There are problems for which no algorithmic solution exists
B) A computing agent must be able to accept input
Both A and B are True
Which of the following refers to the practice of registering a domain name that uses the name or trademark of an existing business, with the intent to sell the name to that business at a profit or to capitalize on that name for some other purpose?
Web personalization is possible using:
Which of the following refers to the process of verifying the identity of the receiver of the data?
Which of the following are models for e-commerce?
Both A and B are e-commerce models
The practice of impersonating a legitimate site for the purposes of stealing money or stealing identity by collecting confidential information such as credit card numbers, names, and addresses is called:
When a system contains ____, it means that there are parts of the system that display random behavior.
A ____ is one of the most popular and widely-used techniques for building computer models.
Discrete event simulation
Which of the following is NOT a reason to construct a simulation model?
Which of the following is NOT an example of a test used to determine if a sequence can be considered to be statistically random?
A model that uses a random number generator to introduce some variability into the data is considered to be:
This means that there are parts of the system that contain random behavior.
Discrete event simulation-
we do not model time as continuous, like a falling body model. But as discrete. That is, we model the behavior of a system only at an explicit and finite set of times.
a mathematical equation specifying the probability that a random variable takes on a certain value.
Uniform Random Number-
generating a random number and taking a value with the equal likelihood.
ASP( Application Service Provider)-
people who for a fee will design your web site and manage it/host it on an ongoing basis.
(internet Corporation for assigned names and numbers) a non profit corporation that took over the task of domain name management from the US government in 1998.
is an entry point web page with links to other web pages (google)
Database management system (DBMS)-
manages the files in a database. Records and fields can be in a single line.
the row in a database
information associated with the tuple
is an attribute or a combination of attributes that uniquely identifies a tuple.
- (structured query language)
is the branch of computer science that explores techniques for incorporating aspects of intelligence into a computer system
a test that allows a human to have interaction with two entities, both hidden from the interrogator. If the human cannot distinguish between the computer and an actual human being, then the computer has passed the Turing test.
a paragraph or page of text that contains all the knowledge we are trying to capture
a formal language sacrifices richness of expression for precision of expression.
Information can be stored in pictorial form as an image
using a mathematical graph to draw a conclusion.
Any knowledge representation scheme that we select must have the following four characteristics:
Swarm Intelligence model-
collective intelligence is constantly updated to respond to current conditions of its environment. (colony of bees)
is a form of software technology that is designed to interact collaboratively with a user somewhat in the mode of a personal assistant.
attempts to mimic the human ability to engage pertinent facts and string them together in a logical fashion to reach some conclusion.
snapping a single frame then moving the sometimes clay model and snapping another frame.