Which type of authorization provides a mechanism to validate both sender and receiver?

Which type of authorization provides a mechanism to validate both sender and receiver?

• Kerberos
• Anonymous
• RADIUS
• TACACS 

EXPLANATION

Kerberos is a computer network authentication protocol that works on the basis of tickets to allow nodes communicating over a non-secure network to prove their identity to one another in a secure manner. The protocol was named after the character Kerberos from Greek mythology, the ferocious three-headed guard dog of Hades. Kerberos An access control system that was developed at MIT in the 1980s. Turned over to the IETF for standardization in 2003, it was designed to operate in both small companies and large enterprises with multiple domains and authentication servers.

 

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Which of these fire extinguishers is best for putting out burning wires?

Which of these fire extinguishers is best for putting out burning wires?

• Carbon dioxide
• Sodium chloride
• Copper powder
• Foam 

EXPLANATION

If a small and contained fire breaks out – for example, if an extension cord begins to smolder -- you could successfully douse it with baking soda. That's right: baking soda, just like the kind you use in the kitchen. Baking soda contains sodium bicarbonate, which just happens to be the substance contained in Class C fire extinguishers, which are best suited for electrical fires. Baking soda produces water, which will effectively cool and smother a small fire.

Class C fires involve electrical equipment, such as appliances, wiring, circuit breakers and outlets. Never use water to extinguish class C fires - the risk of electrical shock is far too great! Class C extinguishers do not have a numerical rating. The C classification means the extinguishing agent is non-conductive. Geometric symbol (blue circle)

CO2 extinguishers have an advantage over dry chemical extinguishers since they don't leave a harmful residue - a good choice for an electrical fire on a computer or other favorite electronic device such as a stereo or TV.

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If an organization takes a full backup every Sunday morning and a daily differential backup each morning, what is the fewest number of backups that need to be restored after a disaster on Friday?

If an organization takes a full backup every Sunday morning and a daily differential backup each morning, what is the fewest number of backups that need to be restored after a disaster on Friday?

• 7
• 6
• 1
• 2 

EXPLANATION

Your network uses the following backup strategy: full backups every Sunday night and Differential backups Monday through Saturday nights. Thursday morning the storage system fails. How many restore operations will you need to perform to recover all of the data?
Answer 2

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Which of the following algorithms is used by MD5?

Which of the following algorithms is used by MD5?

• Block cipher algorithm
• Asymmetric encryption algorithm
• Cryptographic algorithm
• Hashing algorithm 

EXPLANATION

MD5 which stands for Message Digest algorithm 5 is a widely used cryptographic hash function that was invented by Ronald Rivest in 1991. The idea behind this algorithm is to take up a random data (text or binary) as an input and generate a fixed size “hash value” as the output. The input data can be of any size or length, but the output “hash value” size is always fixed.

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Which of the following settings provides the greatest level of wireless security?

Which of the following settings provides the greatest level of wireless security?

• WEP-Shared
• WEP-Cipher
• WEP-Open
• WEP-Closed 

EXPLANATION

 WEP was developed for wireless networks and approved as a Wi-Fi security standard in September 1999. WEP was supposed to offer the same security level as wired networks, however there are a lot of well-known security issues in WEP, which is also easy to break and hard to configure.

Despite all the work that has been done to improve the WEP system it still is a highly vulnerable solution. Systems that rely on this protocol should be either upgraded or replaced in case security upgrade is not possible. WEP was officially abandoned by the Wi-Fi Alliance in 2004.

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What is the address size for IPv6 addresses?

What is the address size for IPv6 addresses?

• 128 bit
• 32 bit
• 64 bit
• 256 bit 

EXPLANATION

Internet Protocol version 6 is the most recent version of the Internet Protocol, the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet.
IPv6 addresses are 128-bit IP address written in hexadecimal and separated by colons. An example IPv6 address could be written like this: 3ffe:1900:4545:3:200:f8ff:fe21:67cf.

 

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Which of the following protocols runs on port 22 and protects the authenticity and confidentiality of the data in transit?

Which of the following protocols runs on port 22 and protects the authenticity and confidentiality of the data in transit?

• FTP
• SSL
• SCP
• DHCP 

EXPLANATION

The SCP is a network protocol, based on the BSD RCP protocol,^[4] which supports file transfers between hosts on a network. SCP uses Secure Shell (SSH) for data transfer and uses the same mechanisms for authentication, thereby ensuring the authenticity and confidentiality of the data in transit. A client can send (upload) files to a server, optionally including their basic attributes (permissions, timestamps). Clients can also request files or directories from a server (download). SCP runs over TCP port 22 by default. Like RCP, there is no RFC that defines the specifics of the protocol. 

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