Cryptography

Security of information results from the need for Private transmission of messages. It is very essential that Security coverage should be provided to the computer systems, including to security to communication channels

Cryptography means hidden writing. Cryptography is used to protect information to which illegal access is possible and where other protective measures are inefficient

The basic idea in cryptography is to take a message in ordinary language, called plain text. This is transformed in some way to produce cipher text. The cipher text can now be sent to the correspondent. He uses another transformation to recover the plain text from the cipher text. The plain text is encrypted or hidden by the first transformation to obtain the cipher text. The cipher text is decrypted by another transformation to obtain the plain text once again. After encryption, cipher text can be transmitted over a data link or stored in a file

Carbon nanotubes

“Carbon nanotubes can in principle play the same role as silicon as in electronic circuits”.

Although the electronics industry is already pushing the critical dimensions of transistors in commercial chips be-low 200 nanometers (billionths of a meter)- 400 atoms wide-engineers face large obstacles in continuing the miniaturization.

Within this decade, the materials and processes on which the computer revolution has been built will begin to hit fundamental physical limits.

Two major problems have so far thwarted attempts to shrink metal wires further.

1. There is as yet no good way to remove the heat produced by the devices, so packing them in more tightly will only lead to rapid overheating.

2. As metal wires get smaller, the gust of electrons moving through them becomes strong enough to bump the metal atoms around, and before long the wires fail like blown fuses

CLUSTERING TECHNOLOGY

The world of commerce relies on highly available information systems to run and manage core business operations such as data warehousing, online transaction processing, and decision support system solutions. Likewise, the worlds of science and engineering also rely on high-performance computing to provide solutions and solve problems,. No matter how fast or available today’s computers are, tomorrow’s applications will invariably demand more. A stage has been reached where stand-alone computers can no longer provide the required levels of availability and reliability. Today’s challenge involves not just providing high availability and optimal performance, but doing so flexibly and inexpensively. Clustering Technology should prove to be a possible solution to address a broad range of system availability and performance requirements.

A Cluster is a parallel or distributed system consisting of independent computers that cooperate as a single system. Generally speaking, clusters offer a way to utilize computer resources more productively in comparison to when the same number of machines in working standalone – the total result is greater than the sum of the separate parts. Clustering Technology aims at providing continuous high availability of resources despite processor and communication failures.

CELLULAR TECHNOLOGY

As we head into the 21st century, wireless communications are becoming a household name. Currently there are over 60 million cell phone subscribers in the world. It is not the cost of the cell phone device that counts but the cost of using it .as a result, the cellular phone infrastructure is being optimized to allow calls to be placed as inexpensively and reliably as possible. Today more than ever, cellular companies are looking for ways to bring down the cal cost to achieve even higher market penetration, especially in metropolitan areas.

Cell phones are available with an incredible array of functions. Depending on the cell phone model, you can store contact information, make task or to-do lists, keep track of appointments and set remainders, use the built calculator for simple math, send or receive email, get information (news, entertainment, stock quotes) from the internet, play simple games, and integrate other devices such as personal digital assistants (PDA), mp3 players, and GPS receivers.

We are going to explore the advent of analog cellular, security flaws and fixes, as well as the dawning of a new age with the proliferation of digital cellular technology.