Computer Networks Quiz Compilation Weeks 10-15

This flashcard set covers key concepts and questions from the Computer Networks lectures spanning weeks 10 to 15, including topics related to data planes, routing, network security, and various protocols.

What is the main function of the data plane of the network layer?

Move packets from router inputs to appropriate outputs.

Given the following forwarding table, what is the outgoing link interface for the destination address 11001000 00010111 00011000 10101010?

1.

If a packet needs to be sent to every host in the network, which transmission mode should be used?

Broadcast.

In the subnet 1.2.3.4/24, how many IP addresses are available?

256.

Which header field cannot be used to define a pattern in OpenFlow?

Destination domain name.

In the abstraction of a network, how are routers and links represented?

Routers as vertices and links as edges.

What is not a good choice for the cost of a link in network representation?

Type of transmission media.

What is the updated value for D(d) after adding c to N' using Dijkstra's algorithm?

17.

What is node a's distance to e after updating its distance vector from node b and d?

60.

What is not a reason for hierarchical routing?

To find shorter paths.

What is the standard inter-AS routing protocol in the Internet?

BGP.

What is not an advantage of SDN?

Scalable routing.

What protocol does the router use to send an error notification back to the source when the TTL value is decremented to zero?

ICMP

Which service is not provided by the link layer?

Forwarding.

How many bits of transmission errors can be detected by CRC using a 4-bit generator?

3.

Does CSMA (Carrier sensing multiple access) completely eliminate collisions?

False.

What protocol is used to translate an IP address to a MAC address?

ARP.

What is the destination MAC address when A sends a packet to B and the frame is transmitted between A and R?

E6-E9-00-17-BB-4B.

Which of the following is not a feature of Ethernet?

Collision avoidance.

What does the Ethernet switch do if the destination MAC address is not in the switch table?

Broadcast packet.

What is not a reason to set up a VLAN?

Insufficient bandwidth.

What is the name of the security requirement to ensure messages are not altered without detection?

Message integrity.

How many possible keys does the monoalphabetic cipher have?

26!.

Which of the following is not a feature of RSA?

Faster than symmetric key cryptography.

What is the number called that is used only once to prevent replay attacks in authentication protocols?

Nonce.

What is not true about hash functions?

It is impossible to find two inputs that will generate the same output.

Which key should Alice use to generate her signature when sending a secure email to Bob with PGP?

Alice's private key.

Which of the following protocols cannot be protected by SSL/TLS?

ICMP.

What is the destination IP address after R1 finishes processing the packet and forwards it to the next hop in the IPsec tunnel mode?

193.68.2.23.

What security hole was introduced by the stream cipher RC4 used in WEP?

RC4 encrypts the message a byte at a time.

What threat cannot be prevented by the firewall at a company’s main router?

An employee tries to access unauthorized data on the file server from his/her office desktop.