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If using... a. Mac/Macbook, install MAMP (not MAMP Pro) b. Windows, install MAMP (not MAMP Pro) or XAMPP c. Other platform, please contact instructor by email or in Breakout Rooms during lab session to discuss Please do not use virtual machines (VMs) nor containers (Docker, etc) unless this has already been cleared with instructor! VMs and containers will only be allowed if you have prior experience using these for Web Server + Database, or if this is the only option for your computer. 2) Configure the Web Server to be Apache (if you are given a choice between Apache and Nginx or other) and configure it to listen on port 8080 (rather than the default of 80 or 8888, etc) 3) Install Wireshark on your computer. Wireshark is also a free download, like MAMP and XAMPP. 4) Start the Web Server (at least Apache, if not all services). 5) Using a text editor create a file named index.html, with the following contents... ZZYZX 6) Place this index.html file from step 5 into the DocumentRoot directory of your Apache Web Server. IMPORTANT: Delete or re-name any other files named index.html or index.php in this directory. Verify that you can browse to index.html from your host computer, by opening a web browser and browsing to http://127.0.0.1:8080 (You should see a page with title “foo” and nothing but the text “ZZYZX”) Once you get this to work, CLEAR THE BROWSER CACHE on your host computer, and answer the following questions... 7) WHAT IS THE FULL PATH OF DocumentRoot DIRECTORY ON YOUR WEB SERVER? (This will be different on XAMPP vs MAMP vs other servers) 8) Open WireShark and start a new capture on the Loopback interface, which is often named lo or lo0 or similar. 9) From the host machine, refresh (or re-browse) to http://127.0.0.l:8080 10) Stop the WireShark capture, and use it to answer the following questions... 11) IN THE TCP THREE-WAY HANDSHAKE THAT BEGINS THE EXCHANGE OF THIS WEB PAGE, WHAT IS THE PORT NUMBER OF THE BROWSER THAT INITIATES COMMUNICATION (sends the first packet)? Hence, we will refer to this packet as packet 0. (Hint: The TCP Three-Way Handshake can be identified from the TCP Flags used in the first 2 packets... SYN, SYN/ACK) BROWSER PORT NUMBER: ________ Hint: packet 0 will be sent from the BROWSER PORT NUMBER to port 8080 (the WEB SERVER) 12) WHAT ARE THE INITIAL TCP SEQUENCE NUMBERS (reported as “Sequence Number (raw)” in the TCP header) USED BY EACH SIDE OF THE WEB PAGE EXCHANGE? HINT: you will need to drill down to the Transmission Control Protocol header and look for the raw Sequence Number field! 13) HOW MANY PACKETS INTO THE CONVERSATION (how many packets after “packet 0”) IS THE PACKET WHICH CONTAINS THE TEXT OF THE WEB PAGE index.html? 14) a. WHAT IS THE FIRST LINE OF THE HTTP HEADER IN THE PACKET WHICH CONTAINS THE TEXT OF THE WEB PAGE index.html? HINT: if you see the status code 304, you probably forgot to clear your browser cache before step 8. No problem...just clear the browser cache and repeat all steps from step 8 forward... b. DOES THIS LINE OF THE HEADER INDICATE SUCCESS OR FAILURE? 15) a. HOW MANY PACKETS INTO THE CONVERSATION (how many packets after “packet 0”) IS THE PACKET WHICH CONTAINS THE GET REQUEST FROM THE BROWSER TO THE WEB SERVER? HINT: this packet will come before the packet from Question 13. b. WHAT IS THE FIRST LINE OF THE GET REQUEST HTTP HEADER (starts with the word “GET”)? c. WHAT TEXT IS IN THE “User-Agent” FIELD OF THIS HEADER? (What does this User-Agent field indicate?) 16) WHICH SIDE (BROWSER or WEB SERVER) IS THE FIRST TO SIGNAL AN END TO THE CONVERSATION (in other words, sends the TCP Fin flag)? 17) WHAT ARE THE TCP FLAGS OF THE LAST PACKET SENT IN THE CONVERSATION? WHICH SIDE (BROWSER or WEB SERVER) SENDS THIS PACKET?