Understanding Network Transmission Acronyms

An Adjunct to Training Classes

Applications engineering of security systems has gained impressive digital tools which include transmission, processing, and protecting the data. To make the most effective use of these new tools, additional knowledge is required in the areas of operating systems, digital video, IT topologies, Internet Protocol, and network security. Although the experienced security dealer integrator probably has earned his wings using some of this technology, there are always additional insights to gain.

OTJ (On the Job) training is when you try to learn a particular device or software application during the course of its first installation. Although this will always be a way you acquire new skills, it is not the best course of learning. Training is available from a variety of sources including from vendors, trade associations, technical schools and publications such as Security Dealer and its wealth of on-line resources. Plus check out this month's, “The Training Center” (page 79).

Video is an area of particular interest, since the issues associated with IP video are generating so much buzz in the industry and also seem to be the object of the most confusion and misconceptions. Contributing to the confusion is the endless list of transmission acronyms you need to be versed on.



This one's tricky. TTL can stand for “transistor-transistor logic,” a common type of digital circuit in which the output is derived from two transistors. The term is commonly used to describe any system based on digital circuitry. TTL also can be “time to live,” a field in the Internet Protocol (IP) that specifies how many more hops a packet can travel before its discarded or returned.



TCP/IP stands for Transmission Control Protocol/Internet Protocol, the suite of communications protocols used to connect hosts on the Internet. TCP/IP uses several protocols, the two main ones being TCP and IP.

TCP/IP is used by the Internet, making it the de facto standard for transmitting data over networks. Network operating systems that have their own protocols, such as Netware, also support TCP/IP.


IR (infrared) telemetry is a line of sight technology used for data transfer between devices, usually over limited distances.



RF (Radio Frequency) refers to a wide range of wireless technologies such as Wi-Fi, cellular, and products which use proprietary formats over regulated frequency segments. These devices include supervised wireless alarms and encrypted voice systems.



Wi-Fi (Wireless Fidelity) was originally a brand licensed by the Wi-Fi Alliance to describe the embedded technology of wireless local area networks (WLAN) based on the IEEE 802.11 standard. As of 2007, common use of the term Wi-Fi has broadened to describe the generic wireless interface of mobile computing devices, such as laptops in LANs. Common uses for Wi-Fi include Internet and VoIP phone access, gaming, and network connectivity for consumer electronics such as televisions, DVD players, and digital cameras.

BPL Technology

A broadband alternative, BPL (broadband over power lines) technology is a proven method for linking small offices, branches and telecommuters. BPL combines power and data on the same wire. It is another option where cable and DSL are scarce or unavailable, or where existing broadband customer service and pricing are poor. The only premises equipment required for BPL is a special modem plugged into an electrical receptacle. Industry forecasts are that by 2012, 33 percent of new broadband customers will access their services using BPL and 13 percent of current broadband users will switch over to BPL.


RS-232 is a standard for serial binary data interconnection between a DTE (Data Terminal Equipment) and a DCE (Data Circuit-terminating Equipment). It is commonly used in computer serial ports. Because the voltage levels are higher than logic levels used by integrated circuits, special intervening circuits are required to translate logic levels, and to protect circuitry internal to the device from short circuits or transients that may appear on the RS-232 interface.

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