Tuesday, April 7, 2009

Happy Birthday to Kahn's Algorithm

This evening I was giving a lecture on TCP timeout and retransmission. We looked at different situations where the client does not get an ack or response to its syn request and the students got to see how the RTO algorithm works in real life, I think they enjoyed the lecture. We also looked at a RFC 793 which covers Transmission Control Protocol and looked at how Microsoft made some changes to their implementation of TCP in 2003 Server so that they could understand how actual implementations can differ from the RFCs.

The last thing that we did was look at the email that Phil Karn sent on A New TCP Retransmission Algorithm. We talked about Khan's research and how is statements on packet radio applied to IEEE802.11 networks, and finally we loked at his famous algorithm and I commented about how he got his research data and tested his algorithm as well as the quality of writing in his informal email as I was looking at it I saw that the message was sent on Tuesday, 7th April 1987 at 20:59. I had shared this with my class on Tuesday, 7th April 2009 at 20:44. Twenty two years to the exact day of the week! Of course this made me very happy and I told the class that if we all had sodas I would have proposed a toast to Phil Kahn.

Monday, April 6, 2009

LaTeX For Lazy People

When it comes to putting figures, equations, tables into Microsoft Word documents or OpenOffice Writer I find it to be a major pain in my head and ass. My head because I have to deal with equation editors, cutting and pasting, alignments and other formatting issues. Two weeks ago I was creating an exam for one of my data comm classes and getting very frustrated with the way that OpenOffice does numbering so I decided to try LaTeX since it seemed to not require any the use of menus, GUIs or other things that I am slowly having less and less patience for.

At first I used Lyx but that was limited in a number of ways, but by studying the source code it generated I started to get the hang of LaTeX
scripting. So in about a week I was just creating my tex documents in vim then converting them to postscript files. Now that I getting comfortable with LaTeX I wonder why I put off learning it for so many years.

It really does make writing easier for me, once I finish my typing lessons the only thing that will keep me from being more productive in my writing will be the time and effort it takes to express an idea well. And as usual that is the hardest part that only practiced discipline can bring.

Sunday, April 5, 2009

To Ian Chang

To Ian Chang

We are all individualists who descend into Mos Maiorum's
. Just like the ancient mariner I stolidly
accept Egyptian divas who drink pearls like Shivas.
Next like Poe you will ask how many Gordon's dance on the head of a Pym!
Don't quote Atlas Shrugged when John Galt rally balked!
So now we can tell Ayn Rand where to get off!

As I & I drive by baobab trees I listen to Kropotkin's 25
theses on the conquest of bread.
but I am still unaware of what he said
Bakunin is nailed to my head
if you think my ideas spring fully formed
consult the Stepping Razor
otherwise let Jah can be praised.
In a chant to Elijah Muhammad with hands upraised.

The kill and go
block the road in this land not described by Wayne's
Western Philosophy.
I once wrote a song about youth even though
I am no childe roland who to the heart of darkness came.
there is nothing here postmod and tradition dates
from 1919 thought they sell you 1416

I am a stranger in my own land so I look to distant shores
beyond pellinore, though every day I thank Napoleon for importing revolution
even though he ruled without constitution in a little Italian car.
I remember staying at the bent prop inn
where the wretched made a hearth and chanted
"we are the good guys in the back of the real!
Who helped Casey to the bat so that he finally makes a steal".

The czars of hegemony challenged her.
The gari eaters live in fear
Maybe at the next road stop
Some OC who dreams of welding a bull pup
will spray me with lead so I must sufficiently beg

To Ian Chang Who Taught Me Elementary break dancing
I dream of smoke machines
with 9 millimeter beams.
Wally sacrifices metals for our lifeline,
a pipeline to the 42 warring states
who celebrate Christmas last with unpaid repasts
of fatted kine soaked in Atlantic brine.

Now that there is a tasty kitchen in Jimeta
maybe Momma will stop tripping.
But outside of St Cloud there is no cheap thrills,
though En Vogue promised me something I can feel.

I ate poundo yam with spinach soup
and danced with baker street runners
in the red hot summer while Skika played
the beats of east African drummers
Hip hop is universal and I am sending another
object of Ioconsicousstream
May developing in C++ be more than a goddamn dream

Cape Town beckons
to travellers who dead reckon.
What makes this an African verse is that is while snow flakes fall on Mount Kilimanjaro
the Beautiful ones, unborn, weep not for the brahmins who came to this world twice.
Like Ogbanjes loudly proclaiming their right to return,

Then again I am thrice blessed, twice in the east once in the west.
If you mark the twain there are no more innocents abroad
just folks who mourn for Denver,
Denver, where Hiram Abiff raised his Moloch
over his Mexican Radio to kill the big beat.

I will stop here since there is no where else to go,
Some will show art in Mayday in the meantime there is the didachae to give me tropic dreams
of eternal machines.