Echo cancellation is the process of removing echo from VoIP calls so customers get quality sound devoid of an echo. All echo cancellation algorithms work by producing several copies of the same signal. Each of these copies is delayed by a time interval at the end of which they arrive with their unique "taps". Echo delay size depends on the total count of taps, which are then weighted and subtracted from the received signal to remove an echo
|CPE (Customer Premise Equipment)|
Equipment such as terminal, modem and related wiring that is essentially owned by either a telephone company or a service provider and is installed at the user end to connect them to the service provider. VoIP service can be implemented in two ways, either a CPE service or network-based hosted service (whereby the subscriber is not required to purchase, install, maintain or upgrade the equipment except IP phone in some cases).
|SBC (Smart Bitrate Control)|
The improved technique of video compression. Variable Keyframe Intervals (VKI) and multipass encoding are the underlying basis of SBC. Files created using this technique can easily be decoded by any MPEG4 video supporting codec.
|CTI (Computer Telephone Integration)|
The technology that helps combine telephony with computer systems. Computers handling calls in call centers or customer care departments are CTI implementations. Here, computers take incoming calls and route them appropriately depending on their call number and caller ID. CTI has replaced traditional PBXs with advanced systems aptly capable of handling incoming calls, outgoing messages, fax and online communication.
|BRI (Basic Rate Interface)|
BRI constitutes one of the two ISDN interfaces, the other being primary rate interface (PRI). The BRI supports two 64kbps B channels, apt for carrying multimedia signal, including voice, image and data. Additionally, BRI supports one 16kbps D channel to carry information related to the data packet and signaling. BRI is also known as 2B+D.
A feature of VoIP systems where the originating device attempts to find an alternative call endpoint when a connection cannot be established to the intended endpoint. In order for dial-peer hunting to work the originating device must have a list of dial peers (all can route a call to the same endpoint, but use different destination routers) so the originating device can proceed to the next in the dial peer sequence.
|TAPI (Telephony API)|
Telephony Application Programming Interface (TAPI) enables integration of computers with telephone services. With TAPI, computers running Windows facilitate phone services such as call dialing and forwarding. Different versions of Windows support varying TAPI versions. TAPI jointly developed by Microsoft and Intel was introduced in 1993. Most modems and telephony devices are compatible with TAPI.
|SS7 (Signaling System #7)|
A signaling protocol for setting up PSTN calls, defining the way information is exchanged between telephone networks and their individual entities. Defined in 1981 by ITU-T, SS7 in the US is commonly known as Common Channel Signaling System 7 (CCS7).
|VPN (Virtual Private Network)|
A private communication network that uses a public telecommunication infrastructure, such as the Internet, to provide secure access to their proprietary data to remote offices or individual users. VPN systems can be hardware based, firewall based or software based. Data encryption, authentication of remote users and mechanisms for hiding or masking information about the system from potential attackers on the public network, are important security features of most VPN systems.
|SIP (Session Initiation Protocol)|
SIP or Session Initiation Protocol is an IETF (see IETF) standard signaling protocol used for creating, modifying and terminating voice, video and data conferencing over packet-switched networks. VoIP systems incorporate SIP at the application layer to successfully integrate IP telephony with other Internet services. Some of the features of VoIP managed by SIP include call setup, routing, authentication, authorization and communication with different service providers.
|MVKS (MERA VoIP Key System)|
A LAN-based PBX designed especially for small to medium enterprises (SME). It is also adequate for large conglomerates with several satellite facilities and offices. Aside from being easy to install and use, MVKS supports complete interoperability with existing network systems.
E911 or Enhanced 911 allows cellular phone and VoIP callers to call 911. Besides, E911 allows tracking the position of the caller as well. A 911 call is usually routed to what is known as the Public Safety Answering Point or PSAP. In turn, the PSAP routes calls forward. Until the mid 1990s, cell phone users could not connect directly to the PSAP. However, an FCC ruling in 1996 mandated cell phone providers to route E911 calls directly to the PSAP. The FCC in 2005 also ruled that VoIP services provide users with the E911 capability. To do so, 911 calls are required to connect to the regular phone network.
|DID (Direct Inward Dial)|
A customized phone line allowing internal users to directly call within the organization without seeking help from front-desk personnel. Though people outside the company can call a DID line through a central telephone number, enterprise users cannot call from outside since DID does not offer a dial tone.
|B2BUA (Back-to-Back User Agent)|
Handles SIP call signaling from its initiation to completion. Based on SIP, B2BUA functions as a SIP User Agent Client (UAC) when initiating a call. On the other hand, it also functions as a SIP User Agent Server (UAS) to receive incoming messages.B2BUA participates in call transfer, call disconnection, maintaining network transparency and billing. Providers use B2BUA to offer multi-feature services to subscribers.
BDSG stands for Bundesdatenschutzgesetz, a Federal Data Protection Act enforced in Germany. The Act, framed in the 1970s aims to protect an individualï¿½??s personal data from unauthorized use.
A VoIP clearinghouse is a feature that enables a local Internet Telephony Service Provider to have a single point of access in its global network. It eliminates the need for multiple traffic sharing agreements with various service providers in various parts of the world.
|Voice over IP (VoIP)|
Voice over IP or VoIP is an IP telephony system, which enables users to transmit voice messages over the Internet. VoIP is superior to the traditional telephony in that it avoids all toll charges, making it less expensive.Examples of low-cost internet voice transmissions are through VOIP services by Megapath.
|REN (Ringer Equivalency number)|
Indicates the extent of inserted impedance a telephone ringer may have. Popularly known as the Ringer Equivalence Number in the UK, REN in the US has been defined as per the Code of Federal Regulations. Traditional telephone systems have a REN of 1, whereas modern systems have a REN much lower than 1.
|ASR (Answer Seizure Ratio)|
Also referred to as call completion rate, ASR is the ratio of successful calls to the total number of calls attempted. ASR can be calculated by using the formula: (successful calls/total attempted calls) * 100
Buttons on a telephone handset that users can program themselves to perform certain functions. For example pressing specific keys followed by punching the digits of a telephone number allows programming that number for speed dialing.
Broadband is a high-speed data transmission medium that can independently support a wide range of frequencies including audio and video frequencies. Broadband is a relative term, as the wider the bandwidth, the more information can be transmitted. Broadband also enables the use of multiple channels or frequencies at the same time by multiplexing the information and transmitting more information in a given time.
With the use of mathematical formulas, compression-decompression defines processing power required, rate of voice compression and attributes of the decompressed speech. Commonly used VoIP codecs are ITU-T G.723.1 and G.729 (AB).
|VPDN (Virtual Private Dial-up Network)|
VPDN shares existing infrastructure such as the Internet to allow remote access to private networks. VPDN offers an inexpensive long distance connection between users and private networks.
VoIP calls can be placed in several ways. You have the option of choosing from a special VoIP telephone, a regular telephone with a VoIP adapter or you can use your computer equipped with microphone, speakers and special software. PC based software solutions for VoIP calling are known as soft phones. These are relatively cheaper, but are not as convenient as VoIP-enabled telephones (hard phones).
In telecommunications terminology, trunking refers to grouping of circuits and switches in a telephone exchange allowing users to share a limited number of connections. In networking, trunking means enhanced link speed by using several cables in parallel.