Computer networks worksheet with answers

What is the default port number for SSH?

1. A53
2. B23
3. C110
4. D22

Which transport protocol provides reliable, ordered delivery with acknowledgements?

1. ATCP
2. BIP
3. CUDP
4. DICMP

What is a network interface card (NIC)?

1. AA cable that links two routers
2. BHardware that connects a computer to a network
3. CA server that stores web pages
4. DSoftware that resolves domain names

A router has routes for 10.0.0.0/8 and 10.1.0.0/16. Which route does it use for a packet to 10.1.5.5?

1. A10.1.0.0/16, because it is the longest matching prefix
2. B10.0.0.0/8, because it was added first
3. CBoth routes, splitting the traffic equally
4. D10.0.0.0/8, because it covers more addresses than the /16

What is the role of a default gateway on a host?

1. AIt is the DNS server
2. BIt assigns MAC addresses
3. CIt is the router used for traffic to other networks
4. DIt is the switch port the host is connected to

How does TLS typically use asymmetric and symmetric cryptography?

1. AOnly asymmetric cryptography is used throughout
2. BAsymmetric methods agree keys and authenticate; symmetric ciphers encrypt the data
3. CSymmetric methods agree keys and authenticate; asymmetric ciphers encrypt all the data
4. DOnly symmetric cryptography is used, with a fixed shared password

TCP congestion control's "slow start" phase:

1. AIs used only by UDP
2. BIncreases the congestion window exponentially until a threshold or loss
3. CKeeps the window fixed at one segment
4. DHalves the congestion window every round trip until a packet loss is detected

Head-of-line blocking in HTTP/2 over TCP occurs because:

1. AEach request needs its own new TCP connection, so later requests wait in a queue
2. BA lost TCP segment delays all multiplexed streams until it is retransmitted
3. CServers cannot handle parallel requests
4. DHTTP/2 uses UDP