0 points: Cinder wants to send Foggy a packet of data across a circuit-switched network. There are four switches between Cinder and Foggy, and each of the five channels has a propagation time of .003 ms. Due to the packet size, each channel will have a transmission time of .07 ms. How long does it take for Cinder to send the data to Foggy? (Don't include the teardown time.)

100 points: Later, Dr. Maple wants to send Cinder a packet about Shapygon. The data-link they share is on a circuit-switched network with six switches between them. Each channel on the link has a propagation time of .002 ms. One of the channels has a transmission time of .01 ms, one has a transmission time of .003 ms, and the others all have a transmission time of .007 ms for this packet. How long does it take for the data to reach Cinder? (Don't include the teardown time.)

0 points: Alice wants to send Bob 20,000 bits of data across a circuit-switched network. If the path that's created by the network is 4000 meters long, has propagation factor 2/3, and bit rate of 200 Mbps. Considering only propagation time and transmission time, how long does it take to send the message, including the setup and teardown of the connection?

100 points: Alice wants to send Bob 50,000 bits of data across a circuit-switched network. If the path that's created by the network is 25,000 meters long, has propagation factor 1/3, and bit rate of 10 Mbps. Considering only propagation time and transmission time, how long does it take to send the message, including the setup and teardown of the connection?

100 points: Alice is sending Bob a datagram with 12100 bytes. Along the way, it passes through a link using Standard Ethernet. How many total bytes are sent from Alice to Bob across that link in the bits? (Include the physical layer header(s).)

0 points: Cinder wants to send Foggy some data across a channel with propagation time .03 ms and a bit rate of 250 Mbps. What is the bandwidth-delay product of the channel?

100 points: Foggy was not directly using the host (a server) that received the message. Instead, her tablet pulls that data from the server remotely. The path used from that server to her tablet consists of links with the following propagation-time, bit-rate pairs:

• .01 ms, 300 Mbps
• .005 ms, 200 Mbps
• .04 ms, 500 Mbps
• .01 ms, 500 Mbps

100 points: The data to communicate over the path in the previous problem is a total of 500 MB. The protocol used to transmit the data will provide the server with feedback about data arriving to the tablet. How much data should the server send before it hears a response?

0 points: A channel has a bandwidth of 2 MHz and 4 signal levels. If there is no noise over the channel, what is the maximum bitrate it can have?

100 points: A channel has a bandwidth of 2.5 MHz and 35 signal levels. If there is no noise over the channel, what is the maximum bitrate it can have?

0 points: A noisy channel has a bandwidth of 4000 Hz and a signal-to-noise ratio of 255. What is the Shannon capacity for this channel?

100 points: A noisy channel has a bandwidth of 3200 Hz and a signal-to-noise ratio of 1023. What is the Shannon capacity for this channel?

0 points: A noisy channel has a bandwidth of 4000 Hz and a signal-to-noise ratio of 255. Assuming we push to the maximum bounds of the Shannon capacity, how many signal levels do we need to attain the full bit rate?

100 points: A noisy channel has a bandwidth of 3200 Hz and a signal-to-noise ratio of 1023. Assuming we push to the maximum bounds of the Shannon capacity, how many signal levels do we need to attain the full bit rate?