Questions about Trace Routes:
Some routers won’t report trace routes (* * *). Some are on the same servers, therefore just * * * as a result.

Complete Network: Every node talks to every other node.
Autononmous systems: When you look at sections of the net -- every node is controlled by 1 company, that system is given an AS #. Once you’re bouncing inside that AS, you’ll see a pattern (* * *) until you exit that system and start seeing trace results outside of it.

Locations are kept voluntarily on servers.
Sometimes, they are inferred. “How else would you know my address is in NYC?” “My laptop does not give this data. Its looking for these router server addresses, therefore, this machine is most likely based there (you’re working out of NYU --> IP addresses can be determined by area (128.) --> NYC).”

Hops vs. Return Times (Sebastian’s Visualization)
The amount of # of hops does not necessarily translate to longer trace route times. Ex: Twitter.

MARKUP - REST MODEL
4 commands GET
POST
PUT - not used much
DELETE - not used much
Most browsers use only GET and POST.
What are the advantages of the REST model?
Minimizes syntax, provides a common language, makes web technology independent of the URL (If Twitter changes its programming language, it doesnt interfere with the site’s experience to the user).

_GET PARAMETERS
http://itp.nyu.edu/~ti8/und_networks/getParamReader.php Passes the parameters directly into the URL. Exposes the Internet query.

_POST Parameters
Passing the request, send the parameters -- all happens behind the scenes. This is not seen through the URL.

RESTIAN MODEL
Has to be technology independent. Don’t expose the Internet (GET POST, HTTP commands) Rest isn’t a protocol, it’s a style. Ex: /webdirectory/webfolder/ Nice and neat structure unlike.

What’s the .htaccess file?
Sets the parameters for the directory Used by the server program to route requests to specific resources


From Tom’s Oct 5 Notes: A simple .htaccess file for doing URL redirects:

  1. enable the Apache mod_rewrite engine:

RewriteEngine On # put in the base path to your directory: RewriteBase /~username/directory # redirect anything after the base directory to index.php: RewriteCond %{REQUEST_FILENAME} -s [OR] RewriteCond %{REQUEST_FILENAME} -l RewriteRule ^.*$ - [NC,L] RewriteRule ^.*$ index.php [NC,L]


HTTP gives you environment variables. See examples here: http://itp.nyu.edu/~ti8/und_networks/ Request Variables : Stuff coming in from Request (time) Server Variables: HTTP gives you as a result of request (char-set, what type of files, language used, type of connection, request_URI, HTTP user agent, etc)

Mentions Phone Finder Language: PHP Identifies the user agent and IP address and sends an email notification. Runs on mobile phones. http://www.makingthingstalk.com/appendixa/69/#more-69

PACHUBE: Tom’s PACHUBE API pet project http://www.pachube.com/feeds/6569 Pachube gives the results in different feed formats. http://api.pachube.com/v2/feeds/6569.xml http://api.pachube.com/v2/feeds/6569.csv http://api.pachube.com/v2/feeds/6569.json

Shows the parameters set in the URL to generate the chart results from his project.

Processing Sketch: Tom will update his class notes to provide the code examples demo’d in class. catUploader (processing sketch takes photo from laptop. snapshot uploads to website) Parses out the _POST command syntax in Processing so Processing can handle the web functionality directly through the TCP connection/open-socket connection.

ASSIGNMENT: REST assignment.
Communication in not-so-realtime. Deliver information to the user through the browser from somewhere else. Update the information they're seeing while they interact, preferably based on input from multiple sources.

Implement or use a RESTIAN model interface.
Ex: You could do simple, build a website that lets people do a few things using REST. Glue 2 restian sites together -> Pachube + Twitter. Input from Twitter --> Pachube or Pachube ---> Facebook? Just know the API structure. Or -- datalog information into a database and display it. Ex: Log values into SQL database, show the data to the public. Think about what structure makes sense, how to structure it hierarchical Due: Week 8 - October 26th.


TOM's NOTES BELOW:

Useful links:

From Making Things Talk:

Huge library of Safari Books Online

A simple .htaccess file for doing URL redirects:

# enable the Apache mod_rewrite engine:
RewriteEngine On
# put in the base path to your directory:
RewriteBase /~username/directory

# redirect anything after the base directory to index.php:
RewriteCond %{REQUEST_FILENAME} -s [OR]
RewriteCond %{REQUEST_FILENAME} -l
RewriteRule ^.*$ - [NC,L]
RewriteRule ^.*$ index.php [NC,L]