Consider a web page for a hypothetical company mydog.com. The HTML file for their main web page, www.mydog.com, is 20,000 bits and contains the following embedded URLs (i.e., the following URLs are contained in the HTML source for www.mydog.com):

http://www.mybird.com/chirp-add.jpg (10,000 bits)

http://www.mycat.com/meow-add.jpg (10,000 bits)

http://www.mydog.com/dog-banner.jpg (15,000 bits)

http://www.mycat.com/puss-chow-add.jpg (10,000 bits)

http://www.mydog.com/dog-chow-add.jpg (10,000 bits)

http://www2.mydog.com/cookie.crumb (5,000 bits)

Consider the operation of the HTTP protocol to download the base page (www.mydog.com) and the embedded objects. Assume:

i) All network links connecting the browser to each server operate at 100 Mbps.

ii) The browser has an internal (empty) browser cache and that there is no proxy cache on the network.

iii) The round trip time from the browser to all servers in the mydog.com domain is 50 ms, the round trip time from the browser to www.mycat.com is 10 ms, and the round trip time from the browser to www.mybird.com is 20 ms. How long would it take to download the dog.com home page and all the embedded objects if the browser used:

a) Up to 4 parallel, non-persistent connections.

b) Persistent, non-parallel connections.

In answering these questions you should start with the time required for the initial TCP handshake (and assume here that the transmission time for the handshake is negligible). You may also ignore the overhead of DNS name resolution, assume there is no queuing or routing delay in the network, and assume that all objects are transferred in one network-layer frame.

c) Given that most computers have a single network interface that can only transmit or receive bytes of data from one connection at a time (i.e., there is no true parallel transmission or reception), why are the use of parallel HTTP connections a good idea?

2. [6+6+2= 14 points) Consider a web page for a hypothetical company mydog.com. The HTML file for their main web page, www.mydog.com, is 20,000 bits and contains the following embedded URLs (i.e., the following URLs are contained in the HTML source for www.mydog.com): http://www.mybird.com/chirp-add.jpg (10,000 bits) http://www.mycat.com/meow-add.jpg (10,000 bits) http://www.mydog.com/dog-banner.jpg (15,000 bits) http://www.mycat.com/puss-chow-add.jpg (10,000 bits) http://www.mydog.com/dog-chow-add.jpg (10,000 bits) http://www2.mydog.com/cookie.crumb (5,000 bits) Consider the operation of the HTTP protocol to download the base page (www.mydog.com) and the embedded objects. Assume: i) All network links connecting the browser to each server operate at 100 Mbps. ii) The browser has an internal (empty) browser cache and that there is no proxy cache on the network. iii) The round trip time from the browser to all servers in the mydog.com domain is 50 ms, the round trip time from the browser to www.mycat.com is 10 ms, and the round trip time from the browser to www.mybird.com is 20 ms. How long would it take to download the dog.com home page and all the embedded objects if the browser used: a) Up to 4 parallel, non-persistent connections. b) Persistent, non-parallel connections. In answering these questions you should start with the time required for the initial TCP handshake (and assume here that the transmission time for the handshake is negligible). You may also ignore the overhead of DNS name resolution, assume there is no queuing or routing delay in the network, and assume that all objects are transferred in one network-layer frame. c) Given that most computers have a single network interface that can only transmit or receive bytes of data from one connection at a time (i.e., there is no true parallel transmission or reception), why are the use of parallel HTTP connections a good idea? 2. [6+6+2= 14 points) Consider a web page for a hypothetical company mydog.com. The HTML file for their main web page, www.mydog.com, is 20,000 bits and contains the following embedded URLs (i.e., the following URLs are contained in the HTML source for www.mydog.com): http://www.mybird.com/chirp-add.jpg (10,000 bits) http://www.mycat.com/meow-add.jpg (10,000 bits) http://www.mydog.com/dog-banner.jpg (15,000 bits) http://www.mycat.com/puss-chow-add.jpg (10,000 bits) http://www.mydog.com/dog-chow-add.jpg (10,000 bits) http://www2.mydog.com/cookie.crumb (5,000 bits) Consider the operation of the HTTP protocol to download the base page (www.mydog.com) and the embedded objects. Assume: i) All network links connecting the browser to each server operate at 100 Mbps. ii) The browser has an internal (empty) browser cache and that there is no proxy cache on the network. iii) The round trip time from the browser to all servers in the mydog.com domain is 50 ms, the round trip time from the browser to www.mycat.com is 10 ms, and the round trip time from the browser to www.mybird.com is 20 ms. How long would it take to download the dog.com home page and all the embedded objects if the browser used: a) Up to 4 parallel, non-persistent connections. b) Persistent, non-parallel connections. In answering these questions you should start with the time required for the initial TCP handshake (and assume here that the transmission time for the handshake is negligible). You may also ignore the overhead of DNS name resolution, assume there is no queuing or routing delay in the network, and assume that all objects are transferred in one network-layer frame. c) Given that most computers have a single network interface that can only transmit or receive bytes of data from one connection at a time (i.e., there is no true parallel transmission or reception), why are the use of parallel HTTP connections a good idea