Computer Networks · Quiz 2 · Sep 2025

A TCP receiver has a buffer size of 30 KB. The sender transmits data at 10 KB/s, while the receiver’s application reads data from the buffer at 6 KB/s. Assuming the buffer is initially empty, after how many seconds will the receiver buffer become full ? Note: Give your answer to two decimal places.

A TCP connection has an advertised window size of 32 KB and a Round Trip Time (RTT) of 80 ms. Ignoring congestion effects, compute the maximum achievable through-put based solely on flow control. Note: Write the answer in KB/s.

An organization has been assigned an address block of 10.25.4.0/26. How many usable host addresses can be assigned to devices in this network?

An organization has 1,800 devices connected in a private network. Each NAT router can handle up to 80,000 simultaneous connections and can serve 300 devices comfortably. If the organization uses NAT (one public IP address per NAT router), how many public IP addresses are required?

An administrator is given the private IP block 192.168.0.0/16. They need to create subnets that can each support at least 500 hosts. What is the smallest subnet mask prefix they can use, in CIDR notation?

At the start of an RTT, the congestion window (CWND) is 15 MSS where the Maximum Segment Size (MSS) is 1200 bytes. TCP is operating in the congestion avoidance phase, and there is one ACK per segment. What will be the new value of CWND (in bytes) after receiving 15 ACKs (i.e., one RTT worth of ACKs)?

A TCP connection has a round-trip time (RTT) of 80 ms and a maximum segment size (MSS) of 1200 bytes. If the steady-state congestion window is 50 MSS, what is the maximum achievable throughput (in Mbps)? Note: Give your answer to two decimal places.

Given IP address A = 172.25.50.22 and B = 172.25.63.10 with netmask 255.255.240.0, compute the **network address** of A (iexpressed in dotted-decimal form).