Answer the following problems.
problem 1) David is implementing XCP. After reading that XCP hardly ever drops packets (less than one in a million), he decides that ACKs are less essential than they are in TCP. Rather than acknowledging each correctly received packet, he decides the XCP receiver must use negative acknowledgements (NACKs) to explicitly inform sender when it is missing a particular range of bytes. What is he overlooking? (Suppose that the last packet in a stream is never lost - that is, the problem is not that the receiver does not know it must NACK the last packet if it is lost.)
problem 2) State true or False for the following.
a) TFRC measures loss event rates using last N loss interval periods.
b) TFRC supports multimedia better than TCP as it adapts to available bandwidth changes more quickly than TCP.
c) TFRC transmission rate is based solely on loss rate and RTT of the connection.
d) TFRC uses sliding window and ACK clocking to make sure that packets are sent out into network at the computed rate.
problem 3) RED gateways can optionally be run in \byte mode," where the average queue size is measured in bytes instead of packets. If David is using SSH, would he chooses routers to operate in byte mode or not? Why?