How DO you study THE internet?







http://www.internetworldstats.com/stats.htm

"If one is to foster an understanding and awareness of how the social and the political are not external to technology, then it is important to understand how the technological is in some sense isomorphic to the social and the political

This book - Protocol - consistently makes a case for a material understanding of technology... This type of materialist media studies shows how the question "how does it work?" is also a question "whom does it work for?" In short, the technical specs matter, ontologically and politically."

"The Internet is a physical network"


Think of other physical 'networks' prior to the Internet

• Water
• Gas
• Electricity
• Telephone
• Cable TV

Internet Traffic

• Text (e-mail/data)
• Image
• Audio
• Video

Spinning vinyl under a microscope

Why don't we hear the abrupt transitions?

• Analog
  
  • continuous signal
  • noise -> signal loss and distortion (cannot distinguish between error and data)
  • imperfect copy
  
  
• Digital
  
  • discrete signal ( 9, 10.2, 12, 14.2, 10.9...etc)
  • magic of mathematics
    • noise/error -> error detection/error correction
      • the sum of all the number I am sending you is X
      
      
      
    • indefinite faithful copies
      • if you detect an error, resend!
      
      
      
    • compression
      • instead of "0000000000000000000000000000000000000000", you can say something like "fourty 0s" (much shorter)
    
    
    

We now know how computers send out signals to the outside world.

Questions we'd like to think about -- what happens when the message enters the "network"

• How does it reach its intended destination?
  
  
• How does snail (physical) mail reach its destination?
• How does a phone call reach its destination?
• Then, we will discuss how the Internet does it!

What does silence on a telephone network sound like?

%ifconfig -a 

to look at MTU (packet) size (byte = 8 bits) and available interfaces

• You don't have a full map of the subway system
  
  
• You can ask the conductor at each station for information
  
• Conductor on certain station will know all the station on the line that goes through the station (eg. conductor on yellow will know all the stations on yellow line. If the station was a transit station with yellow and red line, the conductor will know all the stations on the yellow and red)

Midtown station to Broad St station (Brown line)

Navigating packets to its destination is called "routing"

Imagine the subway system with each line (red, blue, brown...etc) independently administered. Each line knows about its own stations and where it connects with other lines.

• Nodes: individual devices connected (=train stations)
  
  
  
  When nodes under the same administrative domain are connected, they constitute a network
  
  
• network: connect devices within same organization (= train line)
  
• Routers(=transfer stations).
  
  A router is a special device connected to multiple networks, just like a transfer station (Times Square) is connected to multiple lines (Red:1,2,3,9, Yellow:B,D,F,V, Gray:S lines)
  
  
  A router forwards data packets between networks
  
  eg. from network A to network B
  
  Any node that has more than two network interfaces can be a router (Just like any train station with more than two lines can be a transfer station).
  

• (Limited) Scope:
  • Routers know a lot about its own network. (eg. router in the Reed network knows where every computer is in its own network).
  • Routers have limited knowledge outside of its network. (eg. if a packet is going east coast forward it to network B, if it is going to the west coast forward it to network C).
  • No full map of the internet!!
  
  
  
• Best-effort:
  • If one network is down, it will try another route.
  • If a particular network is congested, routers may forward your packet to another network.
  • Routers are allowed to drop (erase, give up on) your packets if it's too busy.
  • Best effort -- no guarantee!!

Looking up routing table using a UNIX command
%netstat -r

The Internet is a network of networks, each with different administrative domain

The Reed network is administrated independently of Wikipedia.

What are the strengths/weaknesses of the Internet system as compared from the telephone network?

- Resilient
- No central control
- Best effort
- Small inexpensive lower quality links are welcome and are allowed to fail


- Military Effort (ARPA) in a Cold War environment
- Often mentioned as designed to survive a nuclear attack.
- Resilient against physical attacks. Perhaps not so to virtual/cyber attacks.

What are the questions one could ask through this diagram?

from A prehistory of the Cloud (pX)
"situate a network... within the same epistemic space as something that constantly fluctuates and is impossible to know"