Virtual Shredder

What does Virtual Shredder mean?

A virtual shredder is a computer program designed to destroy a file completely so that it is no longer recoverable. This is done by deleting and inserting random bits of data into the structure of the file, corrupting it entirely, and then overwriting the storage space where the file was located with random bits of data; with no clear way for a program to know which have been deleted and which bits have been inserted, there is a very low likelihood that the file can be read again in its entirety.

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Network Video Recorder

What does Network Video Recorder (NVR) mean?

A network video recorder is considered a complete Internet Protocol camera recording system and is mostly used in Internet Protocol video surveillance systems. A network video recorder does not use any dedicated hardware for video capture but makes use of special software on a dedicated device. It can record as well as access recorder images and live views. Viewed as the successor to the digital video recorder, the network video recorder can be managed remotely over the Internet or LAN, providing great flexibility to users.

A network video recorder is similar to a digital video recorder. It is comprised of both a computer as well special video management software and does not have a dedicated keyboard or monitor. The basic function of the network video recorder is to ensure remote access to a live video stream from the Internet Protocol camera along with simultaneous recording. It is a true digital system and records the digital images or videos received over the network onto to a hard disk or other storage device. A network video recorder usually has a user friendly graphical user interface, flexible recording, playback capability, intelligent motion detection and pan-tilt-zoom camera control capability. They usually support Windows or Linux environments.

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Offline Storage Table File

What does Offline Storage Table File (OST File) mean?

Offline storage table (OST) files are offline files that store Outlook mail data and make it available to users when they are not connected to the Internet. The offline storage tables store mail data using the .ost extension. These files enable users to work with their offline inbox, offline outbox and make changes that are initially saved locally and are reflected in the server by synchronizing once the computer is connected to the Internet. Users can modify, add or delete the contents of these files just as a file located on the server can be modified.

Offline storage tables are the files that enable the offline mode of the Microsoft Outlook mail client. They are a type of database file that stores the data copied from the mail exchange server. The data copied include inbox emails, calendar and contacts. All such data and attributes are copied into the local OST files while the system is connected to the network and are stored in local storage under the local mail exchange server. The files are synchronized whenever the system connects to the mail server. Thus offline storage tables act as a cached exchange mode for Outlook.

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Wiretrap Trojan

What does Wiretap Trojan mean?

A wiretap Trojan is a type of Trojan virus which records VoIP calls and IM conversations. In the case of VoIP calls such as Skype, the audio data is captured before it can be encrypted and sent over the Internet, and then saved as an MP3 file locally on the infected computer. The messages from an IM application can also be saved to a kind of text file before being encrypted and sent online. The Trojan includes a backdoor to allow the hacker to retrieve the saved files or the Trojan can simply send it to an anonymous address.

Wiretap Trojans are infamous for being used by hackers and government authorities alike since wiretapping, according to government authorities, helps ensure national safety by providing clear intelligence that they can act on immediately if the need calls for it. A wiretap Trojan is like any other Trojan in terms of the way it infects and runs on a host computer, the only difference is its function.

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What does Photoblog mean?

A photoblog is a form of blog in which the focus is on photos and photo sharing instead of the text of the author. The key difference between a regular blog and a photoblog is the heavy use and focus of photos rather than text. Photoblogs tend to be more visually appealing to viewers than text-based blogs.

A photoblog is also known as a plog or photolog.

Similar to blogs, photoblogs can also be hosted on blogging services or on individual domains. In most photoblogs the photographs are organized and posted in reverse chronological order so that viewers can see the latest pictures at the top of the page with any accompanying captions or text from the author. Most of the time, photoblogs have a theme, but in some cases the photos are random and disorganized.

Unlike standard blogging, which at times requires long hours of writing, photoblogging tends to be less tedious and requires less effort and time. Proofreading and editing is negligible, if needed at all. Photoblogs are more visually appealing and thus can do much better in social media marketing and Internet marketing compared to text-based blogs.

However, due to lack of text content, optimization is difficult in the case of photoblogs. Monetization is not easy, as its difficult to get unique visitors and text-based ads are not of much help. Photo bloggers must ensure the copyrights of photos, if taken from other sources, and provide proper credits whenever needed.

Electromagnetic Pulse

What does Electromagnetic Pulse mean?

An electromagnetic pulse (EMP) is a short burst of electromagnetic energy interference caused by an abrupt and rapid acceleration of charged particles, which can damage electronic components by short-circuiting them. An EMP can contain many energy components of the electromagnetic spectrum, from the very low frequency waves to the ultraviolet wavelengths. One very common cause of EMP is lightning strikes, which supercharge ions in the atmosphere and cause electricity in the power lines to surge.

An EMP or transient electromagnetic disturbance is a fairly natural phenomenon, with lightning being the most common cause of fairly low energy pulses that cause localized electrical surges and short circuits in unshielded devices, apart from the damage caused by the lightning strike itself. EMP interference is already generally disruptive to electronic equipment at very low levels, such as causing corrupted data and crosstalk between wired media. Electric motors generate train pulses as the internal contacts rotate, and even the constant switching digital circuitry causes low-level interference that may still be detrimental to other electronic components in its vicinity, which is why shielding is already a major part in the design of electronic hardware.

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T3 Line

What does T3 Line mean?

A T3 line is a dedicated physical circuit that uses high-speed media to transmit data, voice and video at the rate of 45 Mbps. It offers a broadband connection consisting of 672 individual channels of 64 kilobits each.

They are commonly used in applications requiring high bandwidth, such as in research centers and big organizations, to provide uninterrupted data transmission, and other multi-channel services such as email and Internet. Other applications include Internet telephony, large file transfers, telemedicine, video conferencing, credit card processing and more.

A T3 line is also known as digital signal level 3 (DS3).

T3 refers to the trunk line level 3, and is sometimes used interchangeably with DS3 (digital signal level 3). In practice, the DS3 signal is transmitted over a T3 physical line, consisting of a fiber optic cable or coaxial cable. The T3 lines, which are symmetrical and duplex, have equal speeds on both upload and download, and therefore allow simultaneous transmissions without clogging the data lines.

A T3 line is an ideal connection for big business, however, small businesses that cannot afford the full 45 Mb or who may not need such a high capacity, have an option of buying a fraction of the full T3 line. The fractional T3 has some of the 28 lines turned off, and has a lower capacity such as 10 or 20 Mbps.

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Referential Integrity

What does Referential Integrity (RI) mean?

Referential integrity is a relational database concept, which states that table relationships must always be consistent. In other words, any foreign key field must agree with the primary key that is referenced by the foreign key. Thus, any primary key field changes must be applied to all foreign keys, or not at all. The same restriction also applies to foreign keys in that any updates (but not necessarily deletions) must be propagated to the primary parent key.

Consider a bank database, which contains two tables:

  • CUSTOMER_MASTER Table: This holds basic customer/account holder data such as name, social security number, address, gender and date of birth.
  • ACCOUNTS_MASTER Table: This stores basic bank account data such as account type, account creation date, account holder and withdrawal limits.

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Quantum Bit

What does Quantum Bit (Qubit) mean?

A quantum bit (qubit) is the smallest unit of quantum information, which is the quantum analog of the regular computer bit, used in the field of quantum computing. A quantum bit can exist in superposition, which means that it can exist in multiple states at once. Compared to a regular bit, which can exist in one of two states, 1 or 0, the quantum bit can exist as a 1, 0 or 1 and 0 at the same time. This allows for very fast computing and the ability to do multitudes of calculations at once, theoretically.

The ability of a qubit to exist in a superposition state means that a quantum computer is not limited to two states and is therefore able to hold more information, giving quantum computers the potential to be millions of times more powerful than today’s supercomputers. A qubit may represent anything very small, of quantum level, such as atoms, photons and electrons, which, when made to work together, can act like processors and memory.

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What does Three-Way-Handshake mean?

A three-way-handshake is a method used in a TCP/IP network to create a connection between a local host/client and server. It is a three-step method that requires both the client and server to exchange SYN and ACK (acknowledgment) packets before actual data communication begins.

A three-way-handshake is also known as a TCP handshake.

A three-way-handshake is primarily used to create a TCP socket connection. It works when:

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