Consider a 250-meter link, over which a sender can transmit at a rate of 50,000 bits/sec in each direction.
Consider a 250-meter link, over which a sender can transmit at a rate of 50,000 bits/sec in each direction. Assume
The packets containing data (HTTP objects) are 100,000 bits long and contain one object.
The packets containing only control information (like ACKs and requests) are only 12,500 bits long.
That a request is made for a particular webpage. The initial response to that request is a single object (an HTML file). While processing that single object 23 additional objects are requested.
After an object has been completely received, the receiving host can begin creating the next non-persistent connection at the same time it is closing the present nonpersistent connection.
Separate ACKs are always sent (no piggybacking)
Consider how long it would take to obtain all 23 of these objects in each of the following scenarios.
a) [6 points]Assume that each object is requested using a non-persistent HTTP connection. Each non-persistent connection is used to transport one object.
b) [8 points]Assume that the first object is requested using a non-persistent HTTP connection. Then consider the remaining 23 objects requested by the first object. The bandwidth of the medium will be divided into 5 equal channels each with 1/5 of the bandwidth (a transmission rate of 10,000 bps in each of the 5 channels). Simultaneously, one object can be transmitted in each channel.
c) [6 points] Assume a single persistent HTTP connection is used for all 23 objects.