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1 de dez. de 2015

Li-Fi


pureLiFi, the home of LiFi, is recognised as the leader in the field – the use of the visible light spectrum instead of radio frequencies to enable wireless data communication. pureLiFi provides ubiquitous high-speed wireless access that offers substantially greater security, safety and data densities than Wi-Fi along with inherent properties that eliminate unwanted external network intrusion. In addition, the integration of illumination and data services generates a measurable reduction in both infrastructure complexity and energy consumption.


LiFi is a disruptive technology which will shift business models and create opportunities ripe for exploitation. The dominance and lifetime of LED lighting has created a need for new business models in the lighting industry. The need to offer services, including new payment and financing models, creates an unprecedented opportunity for LiFi.


Features

Li-Fi features include benefits to the capacity, energy efficiency, safety and security of a wireless system with a number of key benefits over Wi-Fi but is inherently a complementary technology.

Capacity
Bandwidth: The visible light spectrum is plentiful (10,000 more than RF spectrum), unlicensed and free to use.
Data density: Li-Fi can acheive about 1000 times the data density of Wi-Fi because visible light can be well contained in a tight illumination area whereas RF tends to spread out and cause interference.
High speed: Very high data rates can be achieved due to low interference, high device bandwidths and high intensity optical output.
Planning: Capacity planning is simple since there tends to be illumination infrastructure where people wish to communicate, and good signal strength can literally be seen.

Efficiency
Low cost: Requires fewer components than radio technology.
Energy: LED illumination is already efficient and the data transmission requires negligible additional power.
Environment: RF transmission and propagation in water is extremely difficult but Li-Fi works well in this environment.

Safety
Safe: Life on earth has evolved through exposure to visible light. There are no known safety or health concerns for this technology.
Non-hazardous: The transmission of light avoids the use of radio frequencies which can dangerously interfere with electronic circuitry in certain environments.

Security
Containment: It is difficult to eavesdrop on Li-Fi signals since the signal is confined to a closely defined illumination area and will not travel through walls.
Control: Data may be directed from one device to another and the user can see where the data is going; there is no need for additional security such as pairing for RF interconnections such as Bluetooth.


What if every light bulb in the world could also transmit data? At TEDGlobal, Harald Haas demonstrates, for the first time, a device that could do exactly that. By flickering the light from a single LED, a change too quick for the human eye to detect, he can transmit far more data than a cellular tower — and do it in a way that's more efficient, secure and widespread.




28 de nov. de 2015

Raspberry Pi Zero

Take a look at this new release of Raspberry Pi.


  • A Broadcom BCM2835 application processor
    • 1GHz ARM11 core (40% faster than Raspberry Pi 1)
  • 512MB of LPDDR2 SDRAM
  • A micro-SD card slot
  • A mini-HDMI socket for 1080p60 video output
  • Micro-USB sockets for data and power
  • An unpopulated 40-pin GPIO header
    • Identical pinout to Model A+/B+/2B
  • An unpopulated composite video header
  • Our smallest ever form factor, at 65mm x 30mm x 5mm

Raspberry Pi Foundation

 

19 de nov. de 2015

GitHub - Livros de Programação


Iniciativa fantástica da comunidade GitHub. Agora não tem mais desculpa. São diversos livros de várias linguagens de programação e sobre desenvolvimento de software.

Aproveitem.

Android

C

CPP

CSharp

Engenharia de Software

Metodologias de Desenvolvimento de Software

Git

Haskell

HTML / CSS

Java

JavaScript

LaTeX

Lua

Php

Python

RegEx

Ruby

Shell

Vim

31 de out. de 2015

TeleGeography - Mapa de Cabeamento Submarino


TeleGeography é uma empresa de consultoria e pesquisa de mercado em telecomunicações.

A empresa acaba de lançar em seu site oficial a mais recente versão do seu mapa global de cabeamento submarino. Esta versão contempla 299 sistemas de cabeamento (backbones) que estão atualmente ativos, em desenvolvimento ou com expectativa de ser concluídos até o fim de 2015.

A versão interativa do mapa pode ser acessada aqui.

Fonte: TeleGeography




15 de jul. de 2015

Alcatel-Lucent transmite dados submarinos com tecnologia 300G por 10 mil km

Alcatel-Lucent transmite dados submarinos com tecnologia 300G por 10 mil km


A Alcatel-Lucent bateu um recorde de transmissão de dados através de cabos submarinos. As informações percorreram uma distância de 10 mil km. O feito utilizou, em tempo real, protótipos de uma nova tecnologia de modulação exclusiva de 300 gigabits por segundo.
A taxa de transmissão foi alcançada em ambiente de teste, combinando a tecnologia 300G 8QAM (modulação de amplitude em quadratura 8) da plataforma Softnode 1620 e fibra coerente submarina de segunda geração (CSF-2).
Segundo a fornecedora, a 8QAM pode otimizar sistemas de cabo submarino novos e existentes, permitindo às operadoras entregar mais de 15 terabits por segundo (Tbit/s) por par de fibra em sistemas transoceânicos – equivalentes ao streaming simultâneo de 2,25 milhões de canais de HDTV.
Este é o mais recente de uma série de 24 recordes que a provedora bateu nos últimos 20 anos, todos demonstrando avanços que transformam e otimizam a transmissão de dados de longa distância.


Publicado originalmente em: ComputerWorld