Slotted Aloha question

Ten thousand airline reservation stations are competing for the use of a single slotted ALOHA channel. The average station makes 18 requests per hour. A slot is 125 micro-seconds. What is the approximate total channel load?

Signal to Noise Ratio

In data communication we often use the term "bandwidth" when we refer to the capacity (bits-per-second) of a link. Strictly speaking, however, bandwidth refers to the range of frequencies (highest frequency minus lowest frequency) that can be carried on a link. Using the frequency definition of bandwidth, what must the bandwidth of a 10 Mbps Ethernet link be if the signal-to-noise ratio is 20 dB?

TCP networking

A TCP entity in Host 1 receives a segment from a corresponding TCP entity in Host 3. The received segment has the following header field values set: sequence number = 245553231, acknowledgment number = 45838821, A bit = 1, P bit = 1, U bit = 1, window size field = 1000, urgent pointer field = 5000. In addition, the segment has no options and contains 2000 bytes of data. a. What is the range of sequence numbers for the 2000 incoming bytes contained within the segment? b. What is the next byte that Host 1 is expected to send to Host 3 on this TCP connection? c. What is the range of bytes that Host 1 is permitted to send to Host 3 on this connection? d. What should Host 1 do with the... click for more

binary exponential backoff algorithm

Two CSMA/CD stations are each trying to transmit long (multiframe) files. After each frame is sent, they contend for the channel using the binary exponential backoff algorithm. What is the probability that the contention ends on round , for k What is the mean number of rounds per contention period? Please explain all work.

Virtual Circuits

the following design problem concerning implementation of virtual circuit service. If virtual circuits are used internal to the subnet, each data packet must have a 3-byte header, and each router must tie up 8 bytes of storage for circuit identification. If datagrams are used internally, 15-byte headers are needed, but no router table space is required. Transmission capacity costs 1 cent per 10 bytes, per hop. Router memory can be purchased for 1 cent per byte and is depreciated over two years (business hours only). The statistically average session runs for 1000 sec, in which time 200 packets are transmitted. The mean packet requires four hops. Which implementation is cheaper, and by how mu... click for more