Monday, January 23, 2012

RIP Chris Kalaveras - Killed By Alleged Drunk Driver

Back in October of 2009 at The National Science Foundation ATE 2009 Principal Investigators Conference in Washington, DC I had the chance to talk on camera with DeAnza College students Chris Kalaveras and Paul Nguyen. 

Students that attend the conference spend three days in a variety of seminars, demonstrating and sharing their work with other colleges. These students are the best of the best - it's a competitive and thorough process involving nomination by a professor and selection by a committee in Washington. 

Chris and Paul were nominated and selected. At the conference they displayed and demonstrated how they were taking donated computers, fixing them up and donating them to DeAnza students. Couple of impressive young guys doing great stuff.



On Thursday Chris was killed riding his motorcycle. The driver of the car involved in the accident has been booked on felony DUI charges. Here's the obituary from the Mercury News in San Jose

The Santa Clara County Coroner on Friday identified the motorcyclist who died Thursday (January 19, 2012) evening after a collision with an alleged drunken driver as 25-year-old Christopher Kalaveras of Santa Clara.
Santa Clara police identified the driver as Aaron Keith Taylor, who was booked into jail on felony DUI charges.
Police said the motorcycle and another vehicle collided in a residential neighborhood near Francis and Santa Maria avenues, east of Lawrence Expressway, at 8:45 p.m. Santa Clara paramedics pronounced Kalaveras dead about 10 minutes later.
Police said it was not immediately clear if other factors, such as a slick road, could have contributed to the crash.
Chris was a great kid doing great things and on track to do even greater things. Such a sad and unnecessary loss. If you get wasted - stay off the road.

Tuesday, January 17, 2012

In Protest of SOPA and PIPA 1/18/12

Like many others, I personally and strongly oppose SOPA (Stop Online Piracy Act), also known as House Bill 3261 and the Senate version PIPA (Protect Intellectual Property Act) or S. 968.

Supporters believe the bills, if made law, would expand the ability of U.S. law enforcement and copyright holders to fight online trafficking in copyrighted intellectual property and counterfeit goods


Opponents, like myself, believe that they violate the First Amendment, is Internet censorship, will cripple the Internet, and threaten whistle-blowing and other free speech actions.


Here's a statement from Google - like many businesses, entrepreneurs and web users, we oppose these bills because there are smart, targeted ways to shut down foreign rogue websites without asking American companies to censor the Internet


I encourage you to form your own opinion. If you do agree with Google, Wikipedia and thousands of other companies, tech activists, entrepreneurs and myself -  contact your congressman to tell them you're against the bills, either by calling their office, writing a letter, or sending a prepared message through http://americancensorship.org/

Verizon Buying "Netflix like" URLs

Back from a couple of great conferences in San Francisco and Frisco, Texas - great content, college faculty, admins and staff from around the country doing some amazing work! I get jealous - there are so many great career choices and opportunities for technology students at community colleges!

It's nice to be home though and get back on more of a regular schedule. I've been watching and talking about a few things at the conferences - one of the biggest things is video, especially in the mobile space. It's hot and it's growing - Morgan Stanley reports that approximately half of all mobile traffic today is video and this is expected to grow to 70% in the next four years.

With the rollout of Internet Protocol (IP)-based 4G services like LTE and the move to smart phones, providers are looking for something to replace revenue specifically from SMS (text messaging designed for cell phones). With the conversion to an all IP infrastructure and smart mobile devices, SMS (and text plans) will be rapidly replaced with free IP-based smart phone services like Apple's iChat.

About a month ago there were  rumors going around about Verizon moving into the online video space. What's lacking when it comes to a company like Verizon offering video? The stuff Netflix is doing - content, streaming  technology and subscription plans. So there were also rumors last month that Verizon was considering a bid for Netflix.

Where's it at today? It's still just rumors but Fusible did report that Verizon registered four new domain names on January 12:

http://whois.domaintools.com/verizoninstantvideo.com
http://whois.domaintools.com/verizoninstantmovies.com
http://whois.domaintools.com/verizoninstantmusic.com
http://whois.domaintools.com/verizoninstanttv.com

It will be interesting to watch where this goes.

Wednesday, January 4, 2012

Back From Vacation!

We had a really nice ten day break and now it's back to reality.


I'm out on San Francisco now for our fourth National and Mid-Pacific ICT Centers Winter Conference. This conference runs January 5-6 and features excellent presentations from ICT industry and ICT education representatives. Even in this period of high unemployment, quality ICT education leads to quality ICT employment, and that has a positive impact on the economy – at many levels. We're sharing quality ICT education information, resources and practices, improving ICT education, helping people find good ICT jobs and improving our current economy. I'd like to thank the City College of San Francisco, Microsoft and San Francisco State University for all the work involved in setting up and running this conference.


We leave San Francisco on Saturday morning, flying to Dallas for the Winter Working Connections Conference we are co-sponsoring with the Convergence Technology Center at Collin College. We'll have two fast-paced networking opportunities and conference presentations followed by two days of an in-depth faculty institute at the Collin College Preston Ridge Campus in Frisco, TX.


Great cutting edge content, good people and always lots of fun!

Monday, December 19, 2011

Facebook Friends and Frenemies Report - Why We Add and Remove

There's a new Facebook research report from Nielsen McKinsey's NM Incite titled Friends & Frenemies: Why We Add and Remove Facebook Friends that's pretty interesting. The report looks at the factors that help Facebook users decide whether they want to add someone as a friend or remove an existing person the their friend list. Here's a few details:

  • Knowing someone in real life is the top reason cited for friend-ing someone (82%)
  • Offensive comments are the main reason someone gets the boot (55%)
Additional report details suggests that real world interactions drive online friendships. Meanwhile, sales-oriented and depressing comments help drive friend removals. Facebook etiquette also plays a role, with updating too often, too little or having too many friends a consideration for some Facebook users.

Regarding gender, the report research indicates that men are more likely to use social media for careers/networking and dating – while women use social media for a creative outlet, to get coupons/promos or to give positive feedback. More men add friends based on business networks or physical attractiveness and women are more likely to friend based on knowing someone in real life or remove them due to offensive comments.

Here's an interesting infographic from the report.


Thursday, December 15, 2011

What's a T3 Line?

In my last post I described what a T1, also called a DS-1, line was. Most of us have also heard the "T3 Line" term used. Let's take a look at what a T3 or DS-3 line is.

DS-2 Signal
Before we can describe a DS-3 line, let's first take a look at a DS-2. In that last post we figured out how each DS-1 signal (T1 line or circuit) carries a bit rate of 1.544 Mbps. Four 1.544 Mbps digital DS-1 signals are multiplexed into one DS-2 signal. If we have 4 DS-1 signals per DS-2 signal and each DS-1 signal is 1.544 Mbps we can calculate:


Adding overhead consisting of timing and synchronization bits brings the DS-2 bit rate to 6.312 Mbps.

DS-2 Formation


DS-3 Signal
Each DS-2 signal carries a bit rate of 6.312 Mbps. Seven 6.312 Mbps digital DS-2 signals are multiplexed into one DS-3 signal. If we have 7 DS-2 signals per DS-3 signal and each DS-2 signal is 6.312 Mbps we can calculate:
Adding overhead consisting of timing and synchronization bits brings the DS-3 bit rate to 44.736 Mbps.
And..... 44.736 Mbps.... that's a T-3 line!

Tuesday, December 6, 2011

T1 Lines - What They Are

Most of us have heard about "T1" lines. We know they are some kind of (expensive) communications line you can get from one of the telephone companies. It turns out T1's are part of the Digital Signal (DS) Level System. 

Back in August, I wrote a post titled More on CODECs: Quantization + Sampling Rate = A PCM Wave. In that post I described how a piece of an analog signal is quantized and companded and then given an 8 bit binary code in a process referred to as encoding. From that post, we know to convert an analog signal to a digital signal the analog signal is sampled 8000 times per second and, after matching the instantaneous voltage sample level to one of 256 discrete levels, an 8 bit code is generated for each sample. If we multiply the sample rate by the bit code we get:

(8000 samples/second)(8 bits/sample) = 64,000 bits per second (bps)

So we can say a single analog voice channel, after conversion from analog to digital, requires 64Kbps of digital bandwidth. This 64Kbps is referred to as Digital Signal Level 0 (DS-0) and is the basic building block or channel for the existing digitally multiplexed T carrier system in the United States and the digital E carrier system used in Europe. 

Voice calls are digitally multiplexed using either time division multiplexing or statistical time division multiplexing. Calls are grouped in a way similar to frequency division multiplexing. Let’s look at how this is done.

Digroups or DS-1 signals
Individual analog voice call channels converted to digital and require a bit rate of 64 Kbps each. 24 64 Kbps digital voice channels are multiplexed into digroups or DS-1 signals. If we have 24 DS-0 signals per DS-1 signal and each channel is 64 Kbps we can calculate:


Adding overhead consisting of timing and synchronization bits brings the DS-1 bit rate to 1.544 Mbps - that's a T1!
DS-1 Formation

DS-1 Overhead
We’ve described the process of encoding where an analog signal is sampled 8000 times per second, quantized into one of 256 discrete signal levels, companded it is then given an 8 bit binary code. After a single analog signal sample has been encoded it is multiplexed, with 24 other encoded 8 bit sample signals. This generates a 192 bit (8 bits/sample signal × 24 sample signals) sequence for the 24 sample signals. A process called framing then adds one framing bit to create a 193 bit frame.
DS-1 With Overhead

The framing bits are used to keep the receiving device in synch with the frames it is receiving. Every twelve frames are grouped into a masterframe, also referred to as a superframe. Included within each masterframe is a twelve bit frame pattern from the 12 grouped 193 bit frames This twelve bit frame pattern carries a bit pattern of 000110111001 and repeats itself with each masterframe.

Masterframe

This masterframe bit pattern is used for synchronization.

Remember each channel is sampled 8000 times per second so a single frame represents one eight-thousandth of 24 individual channels or telephone calls. We can also say that, in one second a DS-1 signal transmits 8000 193 bit frames. We can use these numbers to calculate the true DS-1 bit rate which includes both data and overhead (framing) bits:
Each DS-1 signal carries a bit rate of 1.544 Mbps and.... that's a T1!