Telewiki

http://en.wikipedia.org/wiki/Antivirus_software http://en.wikipedia.org/wiki/Anti-spam_techniques

Antivirus (or "anti-virus") software is a class of program that searches your hard drive and floppy disks for any known or potential viruses. The market for this kind of program has expanded because of Internet growth and the increasing use of the Internet by businesses concerned about protecting their computer assets.

Anti-Spam software blocks unsolicited commercial email (UCE). Such "junk" email, commonly referred to as "spam," is generally advertising based and sent wide-scale to a mailing list or newsgroup.

Viruses, spam, and other harmful or unwanted content have a significant impact on companies' bandwidth, storage and email processing costs, while also reducing productivity. More than 90% of today's viruses enter networks through email. Most anti-virus solutions only detect 'known' viruses using signature files. These solutions provide no protection against new threats that spread rapidly through the Internet. Now both known and unknown viruses and spam can be stopped before it reaches your network through proprietary predictive technology. Anti-virus/anti-spam service acts as your first and strongest line of defense by scanning e-mail and eliminating threats such as viruses, spam, and unwanted content before it reaches its intended destination.

http://en.wikipedia.org/wiki/Asynchronous_Transfer_Mode

ATM is a network technology that decreases the number of access lines you need, greatly simplifying technology management. ATM transfers data in fixed-size cells. Because the cells are always the same size, ATM can transmit various types of data – voice, video, and so on – without any one type blocking the line.

When transferring data, ATM creates a fixed channel between two points. (This is different from TCP/IP, which divides the data into packets, with each packet taking a different route to its destination.) ATM's fixed-channel method can reduce overall costs and make it easier to track data usage across the network.

http://en.wikipedia.org/wiki/Bandwidth_(computing)

The amount of data that can be passed along a communications channel in a given period of time. For analog devices, such as standard telephones, bandwidth is the range of frequencies that can be transmitted and is expressed in hertz (cycles per second.) For digital devices, bandwidth is measured in bits per second. The wider the bandwidth, the faster data can be sent.

http://en.wikipedia.org/wiki/Business_Continuity

Business Continuity describes the infrastructure, processes and procedures an organization puts in place to ensure that essential functions can continue during and after a disaster. Business continuity planning seeks to prevent interruption of mission-critical services and to reestablish full functioning as swiftly and smoothly as possible.

Although business continuity is important for any enterprise, it may not be practical for any but the largest to maintain full functioning throughout a disaster crisis. According to many experts, the first step in business continuity planning is deciding which of the organization's functions are essential, and apportioning the available budget accordingly. Once the crucial components are identified, failover mechanisms can be put in place. New technologies, such as disk mirroring over the Internet, make it feasible for an organization to maintain up-to-date copies of data in geographically dispersed locations, so that data access can continue uninterrupted if one location is disabled.

According to a recent Gartner Group document, a business continuity plan should include: a disaster recovery plan, which specifies an organization's planned strategies for post-failure procedures; a business resumption plan, which specifies a means of maintaining essential services at the crisis location; a business recovery plan, which specifies a means of recovering business functions at an alternate location; and a contingency plan, which specifies a means of dealing with external events that can seriously impact the organization. Business continuity has become an increasingly common area of concern since the September 2001 World Trade Center disaster, in which an unforeseen incident created a sudden and severe threat to crucial functions for a number of companies.

http://en.wikipedia.org/wiki/Colocation_centre

A cage or suite in a secure data center designed to house critical IT gear and provide disaster recovery solutions.

http://en.wikipedia.org/wiki/Customer-premises_equipment

The terminating equipment, such as a router, located at the customer or end user's location connecting the data circuit with the customer's network.

http://en.wikipedia.org/wiki/Direct_Inward_Dialing

Direct Inward Dialing. A DID is a telephone number assigned to a dedicated local circuit.

http://en.wikipedia.org/wiki/DNIS

Dialed Number Identification Service. A feature of toll free (800, 855, 866, 877, 888) lines. DNIS numbers are used to automatically identify to the customer phone system a specific employee station to which a call should route.

http://en.wikipedia.org/wiki/Digital_Signal_1

The DS1 (T1) is the most commonly used digital line in the United States. A DS1 is a high-speed data link protocol that has been a standard in the telecommunications industry for more than three decades. A full DS1 transfers data at 1.544 Mbps symmetrically, and is ideal for customers who need a high-speed, reliable connection to the Internet or as one link in their Virtual Private Network (VPN) or Private Wide Area Network.

http://en.wikipedia.org/wiki/Ds3

A DS3 connection is very similar to a DS1 in that it utilizes the same stable technology, follows a similar provisioning and installation process and is subject to the same in depth management and monitoring. In fact, the biggest difference between a DS1 and a DS3 is the size of the 'pipe,' or the amount of bandwidth. As stated above, a DS1 transfers data at a rate of 1.544 Mbps. A DS3, in comparison, carries 28 DS1 signals, transferring data at a rate of 45 Mbps. A DS3 is a solution for companies that require larger amounts of highly available, dedicated bandwidth.

http://en.wikipedia.org/wiki/Digital_Subscriber_Line

DSL stands for Digital Subscriber Line, a broadband technology that uses existing telephone lines and digital coding to create a connection to the Internet from your computer. This link can transmit voice, video and data information at high speeds but its availability and maximum bandwidth is restricted based upon distance from the local central office.

DSL service providers use the same copper-based lines that let you make and receive telephone calls. To send data at high speeds carriers use these copper telephone lines at higher frequencies to process data vs. voice. DSL modems are hooked up at both ends of a telephone line – one at the home office or business and the other in the nearest telephone company switching station. The modems digitally divide your telephone line to transfer data over the copper circuit.

There are multiple varieties of DSL including:

ADSL: ADSL is a technology used for transmitting digital information at a high bandwidth on existing phone lines to homes and businesses. Unlike regular dialup phone service, ADSL provides a continuously available, 'always on' connection. ADSL is asymmetric in that it uses most of the channel to transmit downstream to the user and only a small part to receive information from the user. This recognizes that people tend to be more of a consumer of data than a producer. A slower upstream (upload) speed, 384K, is traded off for a faster downstream (download) speed, 1.54Kbps. This type of service is generally for those who mainly use the Internet for browsing and e-mail.

ADSL2: ADSL2 is a second generation ADSL technology allowing increased bandwidth up to 15MB by 1MB, versus regular ADSL which has a maximum bandwidth availability of 6MB by 768KB.

SDSL: SDSL, like ADSL, is also a technology used for transmitting digital information at a high bandwidth on existing phone lines to homes and businesses. Also providing an "always on" connection, the difference with SDSL is that it is symmetrical. This means that both the upstream and downstream speeds are the same. An individual who signs up for SDSL will have the ability to upload to and download from the Internet at the same speed (192K, 384K, 768K, 1.1M, 1.5M). This type of service is generally for those who require voice or video capabilities in addition to Internet browsing and e-mail.

IDSL: IDSL is available for locations that are too far from the local phone company's central office for either ADSL or SDSL. IDSL is DSL at 144 kbps. IDSL uses ISDN transmission coding, bundling together both ISDN channels on one circuit. IDSL does not use any kind of dial up nor does it involve per-call fees. IDSL can still be a very satisfactory solution for data transmission compared to alternatives such as a dial-up modem.

http://en.wikipedia.org/wiki/Dynamic_bandwidth_allocation

This is the ability to instantly divide large, high capacity bandwidth resources among multiple applications. Each application is provided with only that share of the bandwidth required at that moment, allowing other applications to use remaining bandwidth.

http://en.wikipedia.org/wiki/Ethernet_over_twisted_pair

Ethernet services provided to the customer location over a copper pairs connection. This mechanism uses spare copper cabling previously reserved for landlines, and is dependent on the customer's building location.

http://en.wikipedia.org/wiki/10BASE-FL

Ethernet services provided to the customer location over a Fiber Optic connection. This mechanism is dependent on the customer's building location.

http://en.wikipedia.org/wiki/Ethernet

Ethernet is the most widely installed local area network (LAN) technology. Ethernet was originally developed by Xerox and then developed further by Xerox, DEC, and Intel. An Ethernet LAN typically uses coaxial cable or special grades of twisted pair wires. Ethernet is also used in wireless LANs.

http://en.wikipedia.org/wiki/Firewall_(computing)

A firewall is a set of related programs, located at a network gateway server, which protects the resources of a private network from users from other networks. (The term also implies the security policy that is used with the programs.) An enterprise with an intranet that allows its workers access to the wider Internet installs a firewall to prevent outsiders from accessing its own private data resources and for controlling what outside resources its own users can access.

http://en.wikipedia.org/wiki/Frame_relay

Frame relay is a telecommunication service designed for cost-efficient data transmission for intermittent traffic between local area networks (LANs) and end-points in a wide area network (WAN.) Frame Relay protocol places data in a variable-size unit called a frame and leaves any necessary error correction (retransmission of data) up to the endpoints, which speeds up overall data transmission. When an error is detected in a frame, it is simply thrown away/dropped. The end points are responsible for detecting and retransmitting dropped frames. However, the incidence of error in digital networks is extraordinarily small relative to analog networks. A Frame Relay network is provisioned through a permanent virtual circuit (PVC), which means that you see a continuous, dedicated connection without having to pay for a higher bandwidth leased line.

http://en.wikipedia.org/wiki/Gateway_(telecommunications)

A gateway is a network point that acts as an entrance to another network. On the Internet, a node or stopping point can be either a gateway node or a host (end-point) node. Both the computers of Internet users and the computers that serve pages to users are host nodes. The computers that control traffic within your company's network or at your local Internet service provider (ISP) are gateway nodes.

http://en.wikipedia.org/wiki/High_Availability

In information technology, high availability refers to a system or component that is continuously operational for a desirably long length of time. Availability can be measured relative to "100% operational" or "never failing." A widely-held but difficult-to-achieve standard of availability for a system or product is known as "five 9s" (99.999 percent) availability.

Since a computer system or a network consists of many parts in which all parts usually need to be present in order for the whole to be operational, much planning for high availability centers around backup and failover processing and data storage and access. For storage, a redundant array of independent disks