Tk20 Linux System Administrator Interview Questions and Answers

Three way handshake is a method used in TCP/IP communication to establish a connection between a client and a server.

• Three way handshake involves three steps: SYN, SYN-ACK, and ACK.

• The client sends a SYN packet to the server to initiate the connection.

• The server responds with a SYN-ACK packet, acknowledging the client's request.

• Finally, the client sends an ACK packet to the server, confirming the connection establishme...read more

SSL and TLS are both cryptographic protocols used to secure internet communications.

• SSL stands for Secure Sockets Layer and is an older protocol that has been largely replaced by TLS.

• TLS stands for Transport Layer Security and is the successor to SSL.

• TLS is more secure than SSL and offers better encryption algorithms.

• TLS also supports newer protocols and ciphers, while SSL does not.

• SSL is vulnerable to attacks such as ...read more

Switches work on layer 2 and routers work on layer 3. Types of switches include unmanaged, managed, and layer 3 switches.

• Switches work on layer 2 of the OSI model and routers work on layer 3.

• Switches are used to connect devices within a network and forward data based on MAC addresses.

• Types of switches include unmanaged, managed, and layer 3 switches.

• Routers are used to connect different networks and forward data based ...read more

CIA Triad ensures data security. DOS attack can cause loss of availability.

• CIA Triad stands for Confidentiality, Integrity, and Availability.

• It ensures data security by protecting against unauthorized access, alteration, and destruction.

• DOS attack can cause loss of availability by overwhelming a system with traffic or requests.

• This can result in the system becoming unresponsive or crashing, making the data unavailable...read more

Various types of packets can be used for DOS attacks, including SYN floods, UDP floods, and ICMP floods.

• SYN floods involve sending a large number of SYN packets to overwhelm the target server's resources.

• UDP floods involve sending a large number of UDP packets to consume the target server's bandwidth.

• ICMP floods involve sending a large number of ICMP packets to flood the target server with traffic.

• Other types of packet...read more

Cryptography is the practice of secure communication in the presence of third parties.

• Symmetric-key cryptography

• Asymmetric-key cryptography

• Hash functions

• Encryption algorithms

• Digital signatures

MD5 is a hash function that produces a 128-bit hash value while SHA-2 is a family of hash functions that produce hash values of varying lengths.

• MD5 produces a fixed-length hash value of 128 bits while SHA-2 produces hash values of 224, 256, 384, or 512 bits.

• MD5 is considered less secure than SHA-2 due to its susceptibility to collision attacks.

• SHA-2 is a family of hash functions that includes SHA-224, SHA-256, SHA-384,...read more