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Showing posts from September, 2006

Shannon's 1948 paper on Communication Theory

Just discovered a link to Shannon's "A Mathematical Theory of Communication" . If you were a electrical engineering geek in college, you know who who Shannon was. For the rest, there's Wikipedia .

WiFi Alphabet Soup

After the dot-com boom of 2000 it appears to be the dot-11 boom of 2006. IEEE has come up with an alphabet soup for the wireless standards in the unlicensed band. Wikipedia has a good summary of the alphabet soup IEEE 802.11 - The original 1 Mbit/s and 2 Mbit/s, 2.4 GHz RF and IR standard (1999) IEEE 802.11a - 54 Mbit/s, 5 GHz standard (1999, shipping products in 2001) IEEE 802.11b - Enhancements to 802.11 to support 5.5 and 11 Mbit/s (1999) IEEE 802.11c - Bridge operation procedures; included in the IEEE 802.1D standard (2001) IEEE 802.11d - International (country-to-country) roaming extensions (2001) IEEE 802.11e - Enhancements: QoS , including packet bursting (2005) IEEE 802.11F - Inter-Access Point Protocol (2003) Withdrawn February 2006 IEEE 802.11g - 54 Mbit/s, 2.4 GHz standard (backwards compatible with b) (2003) IEEE 802.11h - Spectrum Managed 802.11a (5 GHz) for European compatibility (2004) IEEE 802.11i - Enhanced security (2004) IEEE 802.11j - Extensions for Jap

The path to immortality

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This is the entrance to the "old shrine" at Sri Ramakrishna Math in Mylapore, Chennai. The arch is emblazoned with this uncompromising line from the Kaivalya Upanishad: न कर्मणा न प्रजया धनेन त्यगेनैके अमृतत्वमानशुः Neither by rituals, nor by progeny nor by riches but by renunciation alone one can attain immortality.

National Highway 47 and the Information Superhighway in India

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A view of National Highway 47 heading south towards Thiruvananthapuram. The single lane accomodates cycles, mopeds, motorbikes, cars, jeeps, buses and lorries. The only change I've seen in the last few years is the increased availability of mobile phones and ,since my last trip there in 2004, the increasing penetration of "broadband" (which is 256 kbps). Virtual connectivity has fast outpaced physical connectivity in a matter of a few years Ads for liqor and fabrics on the roadside have been replaced by hoardings advertising DSL, pre-paid, post-paid and SMS services. Shahrukh Khan's hawking Wireless Local Loop telephony and all high-rise buildings have sprouted cellular towers