Unit 4 quizzes, Unit 5 Quizzes, CSCI 4345 Mid-term study set
Bob and Alice want their secret messages to be shared via a single key. Which cipher according to you is suitable in this case?.
... (Not symmetric-key encryption)
Which of the following methods provide a shared key?. (Select two)
.... (not Diffie-Hellman and El Gamal)
What part of the URL, https://www.utrgv.edu/index.htm, represents the top-level DNS domain?.
.edu
What bit hash value does MD5 produce?. See example below 1e50a2052978e224d3dde95e7e9e7d0a
128
What bit hash value does Secure Hash Algorithm (SHA) produce?. See example below 470ec4a4f28fc4e920145048f3cc948e78cf9657
160
The length of TCP header is minimum _____ bytes long and maximum _____ bytes.
20,60
SFTP, which stands for SSH (or Secure) File Transfer Protocol, usually runs on Port ___ .
22
Perform encryption on the following plaintext M using RSA and find the ciphertext C. Where p = 3; q = 11, e=3; M = 5.
26
If security is a real concern on your network, what length do most experts recommend as the minimum for password length?.
8
Which TCP/IP model layer is closest to the end user?.
Application layer
____ verifies who has the right to gain access to the computer, whether it is your local machine or the Web server.
Athentication
____ governs what an authenticated user is allowed to do.
Authorization
We trust a digital certificate because it contains _________________.
CA's signature
A wireless host needs to request an IP address. What protocol would be used to process the request?.
DHCP
Alice and Bob would like to communicate with each other using a session key but they do not already have a shared secret key. Which algorithm can they use to exchange a secret key?.
Diffie-Hellman
The ports ranging from 49,152 to 65,533 can be used as temporary or private port numbers. They are called the ________ ports.
Dynamic/ private
Which of the following is a public key algorithm based on elliptic curves?.
ECC
The private content of a transaction, if unprotected can be intercepted when it goes through the route over the internet is called __________________.
Eavesdropping
In the commercial and office environment, the most widely used broadband technology is ____.
Ethernet
Which TCP header control bit is set on to terminate a TCP conversation
FIN
(T/F) Generally, it is difficult to intercept transmissions and gain unauthorized access to wireless networks.
False
(T/F) TCP Header contains the IP of the client as well as the IP of the server associated to an end-to-end connection.
False
The operating system encrypts the password for a given user by encoding the information, using a process that is difficult to apply but easy to undo.
False
Transport layer is the _______ layer of the OSI Layered Model
Fourth
What message type is used by an HTTP client to request data from a web server?.
GET
Which application layer protocol uses message types such as GET, PUT, and POST?.
HTTP
Which protocol is used at the application layer of the TCP/IP reference model?.
HTTP
Which of the following is the process of converting a message into a numeric value?.
Hashing
Alice is sending a message to Bob. She wants to ensure that nobody tampers with the message while it is in transit. What goal of cryptography is Alice attempting to achieve?.
Integrity
Why is DHCP preferred for use on large networks?.
It is a more efficient way to manage IP addresses than static address assignment.
Which of the following is the most common version of Message Digest Algorithm (MDA)?.
MD5
Networks come in many sizes and use many different technologies, yet they all need to communicate with each other. What is the key to network intercommunication?.
Network protocols
Which protocol can be used to transfer messages from an email server to an email client?.
POP3
____ is a practice used to illegally obtain sensitive information such as credit card numbers, account numbers, and passwords.
Phishing
What is the main function of Transport layer?
Provide end to end delivery
Alice scheduled a company meeting and shared the location to Bob as "ZGTNU JHII" using substitution cipher, can you help Bob to find the location?.Here is the substitution map used by Alice: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z --> H D M S G K T J W A O I B P R X L Z U C N Y E Q V F
REGUS HALL
The most common public key encryption algorithm is ____.
RSA
Which of the following is based on the idea of using large prime integer numbers for the basis of asymmetric encryption?.
RSA
Which of the following is an update to Secure Hash Algorithm (SHA)?.
SHA3
Which three application layer protocols use TCP? (Choose three.)
SMTP FTP HTTP
Which two protocols may devices use in the application process that sends email? (Choose two.)
SMTP, DNS
____ is the process of using people to get the information you want.
Social engineering
Which type of cipher is a simple coding system that changes one character or symbol into another?.
Substitution
Which set of characteristics describes the Caesar cipher accurately?.
Symmetric, stream, substitution
Which protocol is used the most in the transport layer
TCP
The two main Transport layer protocols are _________________ .
TCP and UDP
Which statement is true about FTP?.
The client can download data from or upload data to the server.
What advantages do asymmetric algorithms have over symmetric ones?.
They allow secure communication over insecure channels
TCP communication works in Server/Client model. The client initiates the connection and the server either accepts or rejects it. ______________ is used for connection management.
Three-way handshaking
(T/F) A technology called broadband has rapidly been replacing modems and analog phone lines for data communications to and from our homes, schools, and offices.
True
(T/F) In a TCP Header the Acknowledgement Number field contains the next sequence number of the data byte expected and works as acknowledgement of the previous data received if ACK flag is set to 1.
True
(T/F) NSF planned and built a national network called NSFNet, which used TCP/IP technology identical to the ARPANET.
True
(T/F) Transport layer takes data from upper layer (i.e. Application layer) and then breaks it into numbered segments and hands over to lower layer (Network layer) for delivery
True
In UDP protocol, the receiver does not generate an acknowledgement of packet received.
True
The main difficulty with a symmetric algorithm is how to securely transmit the secret key.
True
The success of RSA encryption relies on the fact that is a hard problem to find the prime factors for a long integer number n.
True
Your best defense against someone guessing your password is to be smart about how you choose and use your password.
True
What is an advantage of UDP over TCP?
UDP communication requires less overhead.
What statement is true about UDP protocol
UDP is good protocol for data flowing in one direction.
A(n) ____ is the worldwide identification of a Web page located on a specific host computer on the Internet.
URL
What does UDP stand for
User Datagram Protocol
In a TCP Header the field _________ is used for flow control between two stations and indicates the amount of buffer (in bytes) the receiver has allocated for a segment
Windows Size
On a home network, which device is most likely to provide dynamic IP addressing to clients?.
a home router
Public key encryption/decryption is not preferred because:
all of the mentioned
What type of applications are best suited for using UDP?.
applications that are sensitive to delay
The first line of defense against illicit use of, or threats to, computer resources and sensitive information is a strong ____ and authorization process.
authentication
Some laptops now use ____ information such as fingerprint scanning.
biometric
A Registration Authority ___________ issue digital certificate.
can never
A person is downloading a web page from a server of an e-shop. What role is the personal computer assuming in this network model?.
client
A(n) ____ is a set of independent computer systems connected by telecommunication links for the purpose of sharing information and resources.
computer network
Bob and Alice work at Crypty Solutions Inc. They want to share messages in a secure way where it is immune to attacks. What do you think Bob and Alice should implement?.
cryptographic system
Which of the following is the solution of the equation e*d mod m = 1, where m =(p-1)*(q-1) with p, q prime numbers ?.
d = e^(m-2) mod m
Transport layer is the first one which breaks the information data, supplied by Application layer in to smaller units called ___________.
data segments
A security tool to verify the authenticity of the message and claimed identity of the sender and to verify the message integrity is _______________.
digital signature
A ____ uses the same wires that carry regular telephone signals into your home.
digital subscriber line
Which benefit does SSH offer over Telnet for remotely managing a router?.
encryption
Transport layer offers _______ connection between two processes on remote hosts
end to end communicatoin (may be all of them)
(T/F) A digital subscriber line is always symmetric, which means that it has the same transmission speed in the download direction as in the upload direction.
false
Application Layer is ___________ layer of TCP-IP Layered Reference Model.
fifth
What is one of the most effective security tools available for protecting users in a LAN from external threats?.
firewalls
A ____ makes internetwork connections and provides routing between different WANs.
gateway
A(n) ____ takes the password the user originally chooses, chops it up, and stirs it around according to a given formula.
hash function
A ____ captures the user's passwords and credit card numbers (and sends them to someone else), or may even put the computer under someone else's remote control at some point in the future.
keystroke logger
A ____ connects hardware devices such as computers, printers, and storage devices that are all in close proximity.
local area network
A Certification Authority (CA) can be used to avoid a ____________ attack.
man-in-the-middle
Bob and Alice decide to use Diffie-Hellman method. If they are not authenticated to each other, what type of security attack can be expected?.
man-in-the-middle attack
Which two tasks can be performed by a local DNS server?. (Choose two)
mapping name-to-IP addresses for internal hosts forwarding name resolution requests between servers
To try all possible passwords of length k or less would require ____ attempts.
n^1 + n^2 + ... + n^k
In Digital Signature, there is _____ relationship between signature and message.
one to one
In the RSA algorithm, we select 2 random large values 'p' and 'q'. Which of the following is the property of 'p' and 'q'?.
p and q should be prime
For a given user ID, ____ software will first try all words in its built-in dictionary, encrypting each with the well-known hash function and comparing the result with the password file.
password-cracking
All server processes intend to communicate over the network are equipped with well-known Transport Service Access Points (TSAPs), also known as
port numbers
The _______of user should not appear on the digital certificate.
private key
What are two characteristics of peer-to-peer networks?.
resource sharing without dedicated server
What's a common application for asymmetric algorithms?.
secure key exchange
To verify digital signature, we need the ________.
sender's publuc key
Which protocol uses encryption?.
ssh
What is a socket?.
the combination of a source IP address and port number or a destination IP address and port number
What is a characteristic of the application layer in the TCP/IP reference model?.
the creation and maintenance of dialogue between source and destination applications
To solve the problem of two users having the same password, some operating systems keep a third entry for each user in the password file, namely ____ at which the user created the password.
the exact time
