Use this thread to discuss your questions and comments about how to run the lesson.
tell you the truth I am just really lost in this section… I followed how to get on and got into the first example Domain and clicked around and could see things in the tool… but not really sure what all they are supposed to be looking at. I have a fear of teaching this one! And wish this one could of been an example during training. Now again this is coming from a non computer major
This lesson was confusing for me too. I tried to focus on the big picture. I did not go into too much detail about what to look for. I asked my students to look at all the information that was being sent and received when we enter a URL or click on an image. Everything is in ASCII and there is a lot more information than just the contents of the page. All the communication is happening using a fixed protocol which the communicating computers recognize. How the communication is being done (in binary or through which routers) is not important to these computers. They just send messages back and forth in ASCII assuming that the lower layers of the internet are doing their job.
I’d second all of Sangeeta’s suggestions. As she mentioned, the key takeaways are
- Computers online communicate using a protocol called HTTP
- HTTP is done entirely in ASCII and just assumes that all the systems students learned throughout this unit are working and will take care of actually breaking apart the message into packets, routing the packets, and delivering them to the intended recipient. HTTP relies on those systems working but doesn’t care how they do it. This is an example of abstraction.
Don’t forget that we’ve got some great videos to help you and your students visualize how these systems work. This one The Internet: HTTP and HTML gives an overview of how HTTP works. The developer tools are just another way of seeing this protocol in action, but in an interactive way.
Let us know if that helps!
We did watch the video yesterday… and today they are going to explore the interactive developer tools… it just seemed overwhelming when I got into the tool, and I just felt like I needed to give them more guidance on what to look at so they don’t feel that same way. I hope this isn’t a silly question… but when you say everything is in ASCII, you are talking about them looking at the column labeled “name” where all the HTTP, addresses are correct? What is the difference between HTTP 1.1 and quic/1+spdy/3 ? and then I have also seen just the word data under the protocol column… or should I not try to understand that part yet? What I just decided to do was create a Document on Google docs for the kids to get in and fill out and return to me with things they might have questions about, and I am also hoping they might write down things they want to share … and ssshhhh I might learn from them too. Lol
Let me know if you think this is a good or bad idea https://docs.google.com/document/d/1UFzdHPRH03zJfcxGNGC_8v86JyQkh_zO4Ddw4Mb4Oqs/edit?usp=sharing
I found this resource which I will use to help me understand the Network Panel in more detail. For those students who want to drive deeper this may be a great resource. https://developers.google.com/web/tools/chrome-devtools/profile/network-performance/resource-loading?utm_source=dcc&utm_medium=redirect&utm_campaign=2016q3
I definitely will not go this deep into HTTP with my students but will focus on the key takeaways GT mentions.
Heads up on the video for Stage 13. If your students laugh when the inventor of Tumblr is introduced, this is why. Our school district blocks Tumblr because there are a lot of inappropriate blogs on it. I guess I was naive since I have only been on the good ones! The video is excellent and I defended Tumblr and how it can be used!
If you are using Chrome, check out the tutorial video The Network Panel in the Chrome Developer Tools
While in the Network Panel of your Browser:
You are looking at one web page at a time and data pertaining to it.
Be sure to click “refresh” rather often and switch between Sources and Network tabs.
Enter other web site addresses and observe data pertaining thereto.
I like the document, thank you!!
I don’t suppose anyone has a worksheet for the video for this lesson? My school generally frowns upon showing any video without a handout… Thanks!
I made a Cornell Notes for the video, since I couldn’t find anything.
Cornell Notes for Lesson 1.13 Video
Thanks for sharing your Cornell Notes document. Great way for students to process the information from the video.
I need some clarification on U1L13 Resource - HTTP and Abstraction on the Internet
On the second page there is a graphic with HTTP and DNS side by side and connecting to TCP. Please explain why they are side by side. Thanks
Just wanted to mention that this is one lesson where I really didn’t feel supported by the teacher materials. The video was excellent and the vocab fine. But using the devTools on Chrome was not productive and I was not able to help the students. After a student suggested that Firefox made it easier to see Get and Post requests we all went over there for a few minutes, but I had already wasted too much of the period looking at, say, the ms for an image on a page to load. I don’t think I ever did see a get or post request via the Chrome browser and tools. We don’t mind exploring, but a smaller more controlled sandbox would ensure some robust takeaways–if Firefox is the way to go here the Activity Guide should say that. As it is, it was sort of a waste of a half hour in an already long unit. Overall we are really enjoying the materials and activities.
I agree, this lesson is hard every year. Every year that I have taught this lesson, the browser interface has changed and so I never see what I am expecting to see. Firefox may have worked better this year, but may not the next time we teach this lesson. So I’m not sure how much support Code.org can provide in this situation. But, I will definitely pass along your concern to Code.org staff.