BROWSER CACHING Consider an HTTP server and client as shown in the figure below. Suppose that...

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BROWSER CACHING Consider an HTTP server and client as shown in the figure below. Suppose that the RTT delay between the client and server is 30 msecs; the time a server needs to transmit an object into its outgoing link is 0.75 msecs; and any other HTTP message not containing an object has a negligible (zero) transmission time. Suppose the client again makes 90 requests, one after the other, waiting for a reply to a request before sending the next request. origin server server transmission delay (msecs): 0.75 RTT delay (msecs): 30 browser cache Assume the client is using HTTP 1.1 and the IF-MODIFIED-SINCE header line. Assume 40% of the objects requested have NOT changed since the client downloaded them (before these 90 downloads are performed) No, because you can't ever cache all the objects Yes, as long as the time-to-live for the cached items hasn't been reached.. No, because the server is so far away that you'll spend more than 2 seconds to find out. Yes, if all the objects are cached. Sample 1 Sample 2 Sample 3 Current 290 450 360 EstRTT 350 342.5 355.94 356.45 DevRTT 47 50.25 64.56 49.44 TO Int 538 543.5 614.19 554.20 Higher Lower BROWSER CACHING Consider an HTTP server and client as shown in the figure below. Suppose that the RTT delay between the client and server is 30 msecs; the time a server needs to transmit an object into its outgoing link is 0.75 msecs; and any other HTTP message not containing an object has a negligible (zero) transmission time. Suppose the client again makes 90 requests, one after the other, waiting for a reply to a request before sending the next request. origin server server transmission delay (msecs): 0.75 RTT delay (msecs): 30 browser cache Assume the client is using HTTP 1.1 and the IF-MODIFIED-SINCE header line. Assume 40% of the objects requested have NOT changed since the client downloaded them (before these 90 downloads are performed) No, because you can't ever cache all the objects Yes, as long as the time-to-live for the cached items hasn't been reached.. No, because the server is so far away that you'll spend more than 2 seconds to find out. Yes, if all the objects are cached. Sample 1 Sample 2 Sample 3 Current 290 450 360 EstRTT 350 342.5 355.94 356.45 DevRTT 47 50.25 64.56 49.44 TO Int 538 543.5 614.19 554.20 Higher Lower