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"I defend the duty of the teachers to teach the cultivated pattern, and I defend the right of the kids or the adults to learn the dominant pattern. But it is necessary in being a democratic and tolerant teacher, to explain, to make clear to the kids or to the adults that their way of speaking is as beautiful as our way of speaking. Second, they have the right to speak like this. Third, nevertheless, they need to learn the so-called ‘dominant syntax’ for different reasons. That is, the more the oppressed, the poor people, grasp the dominant syntax, the more they can articulate their voices and their speech in their struggle against injustice."

Paulo Freire, 1996

http://www.youtube.com/watch?v=aFWjnkFypFA

Some stats resources

Correlation types (p/r): http://www.fgse.nova.edu/edl/secure/stats/lesson6.htm

Choosing a statistical test and how to run it in SPSS: http://www.ats.ucla.edu/stat/spss/whatstat/whatstat.htm

http://youtu.be/Y8HcBJrBQV0

QoS overview

The most helpful overviews I’ve found to date on QoS for VoIP:

http://www.ciscopress.com/articles/article.asp?p=357102

http://www.networkworld.com/community/node/37507 (You can browse through the preceding several posts until you arrive at the initial discussion on the QoS byte. Interesting reading.)

The key is to tag your VoIP traffic as DSCP class EF (Expedited Forwarding; the numeric value for EF is 46, binary is 101110(00), ToS 184).

The DSCP classes were created by Cisco and are the default markings applied to VoIP traffic. They are the evolution of the IETF’s ToS byte, which allowed the first bits to be used to specify a rough QoS (called “IP Precendence”). The other bits were never used, so Cisco used several of them to create a more granular set of QoS markings. EF 46 is one of them. EF 46’s first bits indicate IP Precedence 5, which is the class for voice traffic on the older IP Precedence system. So, if you mark traffic as DSCP EF, you’re also marking it as IP Precedence 5. Convenient!

Here’s a helpful tool to assess line quality:

http://myspeed.visualware.com/servers/namerica/iad.php?testtype=-1&codebase=mcsiad.visualware.com&location=USA: Dulles, Virginia&ver=9&cm=&map=namerica&lines=&pps=50&bpp=80&codec=G.726 (32 Kbps)&provtext=Visualware&provtextextra=&provlink=http://www.visualware.com