How AKAMAI works ... details of secret technology
rescued from http://web.archive.org/web/20030302122757/http://www.cs.washington.edu/homes/ratul/akamai.html
Here are my conjectures on how Akamai works. These are based on some experiments done on April 4th, 2000 using mainly "dig". These were conducted from some machines at UW and one at MIT.
1. What an Akamaized page looks like?
Suppose you enter www.cnn.com in your browser. This fetches the index.html file from the cnn server. In that file there will be images which will be pointing to the Akamai servers. Those URLs look likehttp://a388.g.akamaitech.net/7/388/21/fc35ed7f236388/cnn.com/images/hub2000/ad.info.gif
http://a1380.g.akamaitech.net/7/1380/175/03202000/www1.jcpenney.com/images/homepagev4/homepage/catalog.gif
http://a620.g.akamai.net/7/620/16/259fdbf4ed29de/www.computer.com/images/learn_more_off.gif
- The number after "a", I think, identifies the customer. So 388 is cnn, 1380 is jcpenny and 620 is computer.com. Note that it is crucial to have different machine name for each customer as will become clear later.
- I am not sure what 7 stands for but it was present in almost of the Akamaized URLs I saw.
- Next is again the customer identifier.
- What the following two identifiers (21 and fade2068e7503e for cnn) represent is not fully clear. A plausible explanation (courtesy Neal Cardwell) is that the 14 digit hex strings are checksums of the content that path refers to. That way the name always changes if the content changes so the akamai caches at the edge don't have to worry about consistency or freshness.
- Next is the customer url itself. The path after that is identical to the path on the customer machine. So the above jcpenny URL and "www1.jcpenney.com/images/homepagev4/homepage/catalog.gif" lead to the same gif.
* update (courtesy John Jacob): The hex string is created using "md5sum [file_name] | cut -c3-16". It can also be replaced by a cache time-to -live value like "1d" for one day, and "15m" for 15 mins.
2. DNS Black Magic
I do not know the DNS system inside out, so the information here could be incomplete or simply wrong. Believe it at your own risk. Below is the chronology of steps that happen when an object from an Akamai server is to be fetched.Step 1
From the top level domain you first get the name server of akamaitech.net domain. Interesting things happen here itself. There are 8 name servers reported z[A-H].akamaitech.net This information obtained is good on the scale of days.Below is part of "dig" output.
The columns are
A couple of points are of interest here.
- The machines at MIT and UW see different information. This could be because they access different NET name servers.
- Another interesting observation here is that IP addresses in the two outputs are more or less (one exception) permutation of each other. What is achieved by having a different IP address for different names is not clear to me. But having the IP addresses returned in different order might achieve load balancing.
Step 2
From one of the name servers above you go and get the name servers for domain g.akamaitech.net. Now this step is where most of the stuff happens. A few observations about the information returned at this step.- The name servers are n[0-9]g.akamaitech.net.
- This information can be cached from 30mins to 1hour.
- The IP addresses of name servers returned are different for different client locations (IP addresses).
- The set of name server IPs returned to a particular client changes with time. So if you access cnn.com at different times (separated by DNS cache expiry) you could be contacting different name servers and thus downloading objects from different servers.
Step 3
In the final step you go to one of the n[09]g.akamaitech.net name server and get the IP address of the machine you are looking for (e.g.: a388.g.akamaitech.net). The server will return two IP addresses for each machine name. For instance, see the partial dig output belowa1388.g.akamaitech.net. 20S IN A 216.52.232.134
a1388.g.akamaitech.net. 20S IN A 216.52.232.149
Akamai caches (courtesy Neal Cardwell)
The akamai machines at the edge are PCs running Linux and a slightly modified version of the squid cache. They are doing on-demand caching rather than push-based replication.
Name server differences
An artifact of the above exploration is the observation that different versions of named might be running in the department (@UW-CSE).
While 128.95.4.1 (bs4) always returns the two IP addresses in different order (to get some sort of load balancing), 128.95.1.6 (bs1) does no such thing.
And the one at MIT (18.26.0.36) seems to be returning the IP addresses in a random order.
Akamai Documents (courtesy Jay Bivens, Bob Devine)
As stated above, these are just conjectures. Corrections/Comments welcome.
Last Modified : 9/03/01
ratul@cs.washington.edu
=====================
A leaked Federal Aviation Administration memo written on the evening of Sept. 11 contains disturbing revelations about American Airlines Flight 11, the first to hit the World Trade Center. The "Executive Summary," based on information relayed by a flight attendant to the American Airlines Operation Center, stated "that a passenger located in seat 10B shot and killed a passenger in seat 9B at 9:20 a.m. The passenger killed was Daniel Lewin, shot by passenger Satam Al Suqami."
The FAA has claimed that the document is a "first draft," declining to release the final draft, as it is "protected information," noting the inaccuracies in reported times, etc. The final draft omits all mention of gunfire. Lewin, a 31 year-old dual American-Israeli citizen was a graduate of MIT and Israel's Technion. Lewin had emigrated to Israel with his parents at age 14 and had worked at IBM's research lab in Haifa, Israel. Lewin was a co-founder and chief technology officer of Akamai Technologies, and lived in Boston with his family. A report in Ha'aretz on Sept. 17 identified Lewin as a former member of the Israel Defense Force Sayeret Matkal, a top-secret counter-terrorist unit, whose Unit 269 specializes in counter-terrorism activities outside of Israel.
The videos of the impact corroberate each other (mostly, but fakes do exist!)
Therefore some of the videos must be authentic.
Since (hollow aluminium) airplanes do not fly through steel and concrete, the image of the aeroplane that we all saw must have been a holographic projection.. probably onto a missile..
http://u2r2h-documents.blogspot.com/2007/10/u2r2h-holo-tvf-missile-flyby-projector.html
and here it is.
Lewin, a graduate of MIT and Israel's Technion, lived with his wife, Anne, and two sons, Eitan and Itamar, in Brookline, Mass., where he helped run Akamai Technologies -- which he co-founded, nearly becoming a billionaire in the dot-com stock boom. He previously worked for IBM's research lab in Haifa, Israel. His parents and brothers all live in Israel.
Lewin belonged to Sayeret Matkal - this outfit specializes in aircraft hostage rescues
Daniel Lewin of Akamai. Before founding Akamai, Lewin was a captain in Sayeret Matkal, a top-secret Israeli anti-terrorist
unit.
In the OFFICIAL FAIRY TALE of Flight 11 (which did not exist!), Lewin was seated one row behind two of the hijackers and one row in front of one other hijacker. What are the odds that an Israeli anti-terrorism soldier would be sitting near all of these hijackers?
Akamai Technologies, Inc. (NASDAQ: AKAM) is a company that provides a distributed computing platform for global Internet content and application delivery, headquartered in Cambridge, Massachusetts. The company was founded in 1998 by then-MIT graduate student Daniel Lewin, along with MIT Applied Mathematics professor Tom Leighton and MIT Sloan School of Management students Jonathan Seelig and Preetish Nijhawan. Leighton still serves as Akamai's Chief Scientist, while Lewin was killed aboard American Airlines flight 11 which was crashed in the September 11, 2001 attacks. Akamai is a Hawaiian word meaning smart or intelligent.
Akamai transparently mirrors content (usually media objects such as audio, graphics, animation, video) stored on customer servers. Though the domain name (but not the subdomain) is the same, the IP address points to an Akamai server rather than the customer's server. The Akamai server is automatically picked depending on the type of content and the user's network location.
In addition to image caching, Akamai provides services which accelerate dynamic and personalized content, J2EE-compliant applications, and streaming media to the extent that such services frame a localized perspective.
As of 2008, Akamai started to release a quarterly "State of the Internet" report, where they present data and trends regarding traffic and bandwidth adoption. Their first report gathered information about 125 countries.[1]
Akamai's customers include many large internet, media and computer companies including the BBC.[2]
Arabic news network Al-Jazeera was a customer from 28 March 2003 until 2 April 2003, when Akamai decided to end the relationship.[3] The network's English-language managing editor claimed this was due to political pressure.
In March 2005, Akamai signed an agreement to acquire Speedera Networks for 12 million shares of Akamai common stock, valued at $130 million at that time.[5] Both companies also agreed to halt pending lawsuits involving trade secrets and patent infringement.[6] The acquisition was completed in June 2005.[7]
On April 12, 2007 Akamai acquired Red Swoosh in exchange for 350,000 shares of Akamai common stock.[8] The acquisition of Red Swoosh was valued at approximately $15 million, net of cash acquired.
Earth's magnetic field:
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