On 802.11 networking

Lately I've been having all sorts of Network layer issues on my laptop. For some reason although a Datalink connection is (as Professor Ma would say) entablished with the Access Point, the negotiation of a DHCP lease just isn't happening. I've had to steal access from a neighbour via a painfully slow Rogers connection.

For those aspiring Network Analysts, here is an interesting question. How did I know my neighbour is using Rogers? Well its actually pretty trivial but still useful to know. First using the website What is my IP gives me the address of the WAN interface on the neighbour's "Router". Next I go to Traceroute.org and inspect a few different Looking Glasses - why a few? Just be sure.

Lets consider this example, suppose the neighbour's IP address is, say 99.233.100.100 (from What is my IP). Now lets plug that IP address in to Quest USA (ASN 209) and Telus (ASN 852). (We ensure to select BGP not Ping or Traceroute, although those can be interesting too depending on what we are up to).

From Quest we see:

sh ip bgp 99.233.100.100
BGP routing table entry for 99.233.0.0/16, version 570055897
Paths: (2 available, best #1, table Default-IP-Routing-Table)
Not advertised to any peer
  174 812
 205.171.0.96 (metric 10) from 205.171.0.149 (205.171.0.149)
   Origin IGP, metric 0, localpref 80, valid, internal, best
   Community: 209:888 209:889
   Originator: 205.171.0.96, Cluster list: 205.171.0.149
174 812
 205.171.0.96 (metric 10) from 205.171.0.150 (205.171.0.150)
   Origin IGP, metric 0, localpref 80, valid, internal
   Community: 209:888 209:889
   Originator: 205.171.0.96, Cluster list: 205.171.0.149

And from Telus we get:

show ip bgp 99.233.100.100
BGP routing table entry for 99.233.0.0/16, version 11888182
Bestpath Modifiers: deterministic-med
Paths: (1 available, best #1)
Not advertised to any peer
  852 812
 154.11.63.85 from 154.11.63.85 (154.11.0.161)
   Origin IGP, localpref 100, valid, external, best

Now notice in both answers (Telus and Quest) the bolded lines, I did the bolding. Lets see those two lines:

Quest: 174 812
Telus: 852 812

In both cases ASN 812 appears, now interestingly Quest is supposed to be ASN 209, but they show up as 174 - which happens to be Cogent Communications. How do I know Cogent is ASN 174, because I have almost every damned ASN under 600 memorized... no I don't really, but I've been doing so much Border Gateway stuff lately that I feel like I've got them all memorized. But I do know that 174 is Cogent, not Quest, and even if I did not already know that, I could go to ARIN and ask my friendly neighbourhood RIR, use the string 'a 174' without the single quotes. What about 812? Well we know from the Looking Glass section that 812 is Rogers.

My neighbour is on a shitty Rogers connection, which is why I am not working on my article on space planes but am instead writing about the wonderful World of Internet Routing. As soon as I get my own wireless sorted out I'll get back to other things, I promise.

Now that I've done all that I notice something really interesting, Cogent's POC (Point of Contact) is a NOC (Network Operations Centre) that's very interesting, I always though POCs had to be individuals. Well maybe I can change my ASN POC to be a NOC, but in the meantime I really should be fixing the DHCP issues on my IBM so that I can use TCP, UDP, IP and all the wonderful applications like HTTP, FTP and my favorite, TCP port 17! (Yes the excessive use of acronyms there was intentional.)

Caught up in ideals

I've been doing a lot of research on airplanes, when I'm not watching CNN. But I just found something I hope my grandchildren can find one day.


Sometimes life does immitate art.


This is from Barack Obama in Baltimore MD. I'm not sure who BHO reminds me of more, Jack Kennedy or Jed Bartlet. But either way I hope he wins, the United States needs him.

On Flight and the limitations of the Jet Engine.

Even before World War II there were known limitations to the speed that aircraft could fly. Propellers would spin faster and faster and as they spin up the tips would go faster than sound. Now when an object breaks the sound barrier it causes shockwaves which unsettle the air and cause turbulence. The turbulence in turn destroys the airflow and hence the thrust of the propellers. The fastest propeller driven aircraft traveled about 400 mph. or about 650 km/h.

Prior to The War engineers on both sides of the English Channel were at work on a new type of engine. Using a turbine to draw air in and a jet of hot exhast gas to turn the tubine and push on the way out the turbojet (see the image below) rendered previous propeller aircraft obsolete by the end of The War.

Photo from Propulsion - Intermediate.

Within ten years of VE and VJ day turbojet aircraft like the Lockheed F-104 Starfighter (below) could fly almost twice the speed of sound.

(Photo from Wikipedia.)

Despite the tremendous improvements from the turbine driven Turbojet there were limitations. For one thing, turbojets are gas guzzlers. Newer technologies, like the Turbofan engine provide comparable, if not better thrust, while consuming fuel at a far more relaxed pace. (In fact very likely your holiday jet is driven by a Turbofan.) But fundamentally a Turbofan is in many respects little different from a traditional turbojet, both engines have a turbine and that turbine spins at a speed related to the forward speed of the aircraft. Now imagine, you are a turbine blade, I know its not the sort of position one imagines themselves in all that often. You are spinning round a shaft (turbine) thousands of times a minute, super highly compressed air is blasting past under such pressure that kerosene is igniting spontaneously. Now lets go faster. At some point the turbine blade will break, we just cannot make them strong enough and durable enough. That turbine breaking point corresponds very roughly to an aircraft forward speed of three and one half times the speed of sound.

Well jets are fast, until you spend 12 or 14 hours over the Pacific ocean in economy class, if you are more than about 4 feet tall, those 12 or 14 hours feel like eternity. There has to be a way to make airplanes go faster.

As it turns out long before Frank Whittle and Hans Von Ohain had dreamed up the jet engine Rene Lorin of France had already patented a faster technology.

The limit to the speed of a jet engine propelled aircraft is the turbine, so the obvious solution? Remove the turbine. Imgine an aircraft racing forward at something near, or faster than, the speed of sound. Now as the aircraft moves forward it displaces huge amounts of air, but some of that displaced air is directed down a tube. As the air rushes down the tube some kerosene or hydgrogen is injected into the tube, then suddenly the tube constricts. The temperature will shoot up causing the kerosene or hydrogen to ignite, pushing the temperature way up. The air cannot expand, there is no room, so the pressure builds, then suddenly the tube ends and the super dense, super hot air expands rapidly, creating thrust. Such an engine, or Ram Jet can accelerate an airplane to something between three and five times the speed of sound. Which sounds great until you realise you are still going to spend something like six or seven hours flying to New Zealand to tell Peter Jackson that Lord of the Rings needs a Tom Bombadil.

(Photo from Wikipedia.)

The problem with Ram Jets is that as the aircraft goes faster, the air compresses to higher pressures and temperatures which ultimately make the heat from the burning fuel a negligable factor. Put simply, as the heat from compression builds, the heat kills the engine's effiency to the point where speed will effectively shut the engine down.

What is required is an engine that will not compress air after the addition of fuel.

(Image from: Wikipedia.)

Such an engine was first conceived in the 1950s but only in recent years have the first Supersonic Combustion RAM or SCRAM Jet seen light of day.

The SCRAM Jet is significant becuase it makes possible a dream. A dream of affordable Earth Orbit. In my next posting I hope to describe what I believe space flight will look like in about 30 years, which when you think about, is almost the age of the Space Shuttle.

Super Duper Tuesday

Its Super Duper Tuesday. I tried to get some good informed data from The Daily Show. But Comedy Central's website SUCKS. I cannot watch reruns of old shows, I cannot watch clips linked to from other sites of old shows - the videos just don't work. Here in Canada, and I imagine in the States too, The Comedy network has been running an ad campagin for their website saying "with 95% less suckage", well, I've got really bad news guys. Release Youtube.com! At least The Daily Show on Youtube worked. I swear I'm gonna have to get a DVR becuase there is just no way I can stay up until 11:30 for my nightly fix of John Stewart. (They even stopped running a rerun of The Daily Show at 9:30pm, the rotten scum.)

In other news, would Billary come to his/her senses, the 90s are over. The country needs a real president, desperately. Cleaning up after four years of the first Bush was something Bill was clearly underqualified for, eight years of this spawn is going to take 30 years of great presidents and Clinton's appeal to an easy escape just won't work. The country needs to be modivated, the country needs hope, the country does not need another blow job flake.

I am going to watch CNN, with my fingers crossed. Any American's reading this, here's a big hint in a language that is natively American. You own a shop, business is doing badly, what's the first thing you do? Hang out a big sign "under new management" and hope to everything holy the World notices and comes back to do business with you. And by god, electing another white guy or a Clinton is so totally the message you don't want to be sending.