®
White Paper
®
The Business User’s Glossary to VoIP Introduction This glossary provides a useful list of common terms and their definitions to help nontechnical business users familiarize themselves with Voice over IP (VoIP), also known as Internet telephony. If you find yourself responsible for procuring a new VoIP system or commenting on a potential contract, you will find many of the terms here mentioned during technical conversations when determining the requirements of a project and working through the quotation process. Acoustic echo. Background noise that one or both parties on a VoIP call can hear; typically caused by an issue between the microphone and the speaker, less commonly by a problem within the network ATA (Analog telephone adaptor). This special adaptor can be connected to a traditional analog telephone to make it useable on a digital network Backbone. The high-speed network that connects cities; backbones are often owned and maintained by large telephone companies such as AT&T and Sprint Bandwidth. The measurement of the amount of data that can be transmitted from point A to point B every second, typically measured in kilobits per second (Kbps) or megabits per second (Mbps) BRI (Basic rate interface). Sometimes used interchangeably with Integrated Services Digital Network (ISDN), BRI provides a bandwidth of 128 Kbps; now considered an older, outdated technology but still used outside the United States overseas. BYOD (Bring Your Own Device). Refers to the practice within IT departments of allowing employees to use the mobile device of their choice and that they own within the company’s network Cable modem. A device that connects a home or office network to the Internet service provider’s network infrastructure at a set bandwidth
About Ziff Davis B2B Ziff Davis B2B is a leading provider of research to technology buyers and high-quality leads to IT vendors. As part of the Ziff Davis family, Ziff Davis B2B has access to over 50 million in-market technology buyers every month and supports the company’s core mission of enabling technology buyers to make more informed business decisions. Copyright © 2014 Ziff Davis B2B. All rights reserved.
Contact Ziff Davis B2B 100 California Street, Suite 650 San Francisco, CA 94111 Tel: 415.318.7200 | Fax: 415.318.7219 Email:
[email protected] www.ziffdavis.com
Ziff Davis | White Paper | The Business User’s Glossary to VoIP
Call hunting. A method by which a customer support service center allows incoming phone calls to roll over to the next available customer service agent CDR (Call detail record). The detailed documentation of any given call, including identification of the caller and receiver and duration; often used for billing purposes but also useful for technical troubleshooting Client. The end device (telephone handset, mobile phone, desktop) receiving a VoIP call; also referred to as the end point Clipping. Occurs when parts of a phone call are lost during a conversation, resulting in partially heard words and the other party “breaking up” Codec. The algorithm used to encode the user’s voice in a digital format, and then decode it on the receiving end to hearable audio Compression. The process of compacting data so that it uses less bandwidth; the amount of compression is associated with the codec in use Conference bridge. A feature that allows three or more parties to participate in one phone call; on a VoIP network, a limited number of conference bridges will be available for use at any one time CPE (Customer premise equipment). Refers to the hardware that the customer owns or rents and maintains; considered distinct from the telephone provider’s network CSU (Channel service unit)/ DSU (data service unit). Refers to hardware typically used to connect a T1 line between the provider’s network and the customer’s network; an older term more likely encountered outside the United States DHCP (Dynamic Host Configuration Protocol). The protocol by which most VoIP telephone handsets and devices receive their IP address dynamically (rather than statically) DID (Direct inward dialing). A features that allows the IT department to assign a standard 10-digit telephone number to an internal extension within the organization for direct access DSL (Digital subscriber line). A technology that allows a phone company to transmit digital data over existing copper wiring, usually at 128 Kbps; a slowly fading technology DSU (data service unit). See CSU (Channel service unit)/DSU (data service unit) E1. The European equivalent of a T1 line; provides a bandwidth of 2.048 Mbps typically divided into 30 discrete 64 Kbps channels, allowing for 30 simultaneous phone calls on a VoIP network
ziffdavis.com
2 of 5
Ziff Davis | White Paper | The Business User’s Glossary to VoIP
E911. The standard for providing emergency 911 service from Internet telephones (typically, a VoIP phone cannot be used until the E911 service has been configured) Echo cancellation. A process used to eliminate acoustic echo from calls Fax server. A server on the VoIP network through which client computers can send faxes Frame relay. An obsolete infrastructure technology that allowed telephone companies to send digitized data between networks; occasionally encountered outside the United States G.729. A high-compression codec that digitizes voice calls to use 8 Kbps of bandwidth Gateway. Typically the last piece of hardware between the customer premise equipment and the telephone company’s network H.264. A widely adopted codec with high compression to transmit audio and video in one combined signal H.323. A widely adopted but older codec for transmitting audio and video in one combined signal Hard phone. Refers to the physical VoIP handset that sits on a user’s desk HUD (Heads-up display). In more recent VoIP systems, a digital display of the telephone that appears on the user’s computer Internet congestion. Occurs when there is more data traffic on the telephone company’s network than it can handle, adversely affecting the quality of VoIP calls IP address. The unique public Internet address assigned to a device ISDN (Integrated Services Digital Network). Sometimes used interchangeably with BRI, an ISDN provides a bandwidth of 128 Kbps; now considered an outdated technology but still available outside the United States ISP (Internet service provider). In the past, the ISP was a distinct company from the traditional telephone company, offering only data transmission services; Today, companies like Verizon provide both services IVR (Interactive voice response). Alternate term for a voicemail system Kbps (Kilobits per second). A standard measure of bandwidth transmission rate Latency/lag. Refers to the amount of time in milliseconds (ms) it takes for a data packet to travel from point A to point B; used when troubleshooting VoIP call quality
ziffdavis.com
3 of 5
Ziff Davis | White Paper | The Business User’s Glossary to VoIP
LTE (Long term evolution). A wireless broadband technology which supports roaming Internet access for mobile phones and devices Mbps (Megabits per second). The industry-standard default measure of bandwidth transmission rate NAT (Network address translation). A method of manipulating information in IP packets to allow multiple devices (computers, phones) to communicate over one public IP address Packet loss. Refers to actual data being lost during transmission because of high Internet congestion or other network problems; can adversely affect VoIP call quality PBX (Public branch exchange). Refers to older, internal, private phone systems within an organization; VoIP systems today are slowly replacing PBX systems POP (Point of presence). The facility at which multiple company and home networks are connected to the telephone company’s network; the closer the POP to your company or home, the shorter the transmission distance Port. Refers to the physical location on a switch at which a device (computer, telephone) connects to the company’s network POTS (Plain old telephone system). Refers to a traditional analog phone working over copper telephone lines PRI (Primary rate interface). Alternate term for T1 and E1 PSTN (Public switched telephone network). Refers to the international hub of a telephone company’s circuit-switched telephones QoS (Quality of service). Within VoIP networks, refers to the configured preference for VoIP calls over Internet browsing or media streaming RJ-11. The traditional physical connection for analog telephones RJ-45. The standard physical connection for digital devices such as computers and VoIP phones Router. The hardware within a company’s network that directs data traffic to designated clients; a company’s network security measures are configured in the router SIP (Session Initiation Protocol). An open standard that allows devices to initiate and complete a VoIP call and different manufacturers’ hard and soft phones to work together on the same network Soft phone. Refers to an application installed on the user’s computer that provides the traditional functionality of a hard phone but without the need for a physical device
ziffdavis.com
4 of 5
Ziff Davis | White Paper | The Business User’s Glossary to VoIP
Switch. The standard piece of network hardware within a company for joining computers and hard phones; available in various sizes and designated by the number of ports they contain (e.g., a 24 port switch can connect up to 24 devices on the network) T1. The standard data transmission line in North America; provides a bandwidth of 1.544 Mbps typically divided into 24 discrete, 64 Kbps channels, allowing for 24 simultaneous phone calls on the VoIP network T3. A larger standard data transmission line in North America; provides a bandwidth of 44.736 Mbps typically divided into 672 discrete, 64 Kbps channels, allowing for 672 simultaneous phone calls on the VoIP network UC (Unified communications). Refers to the overarching system within an organization consisting of voice, video, instant messaging, and fax that allows all components to work together seamlessly UCaaS (Unified Communications as a Service). Refers to a hosted provider service (i.e., a cloud service) that includes all the communications tools in an organization, such as voice, video, instant messaging, and fax, working seamlessly together in a hosted model VoIP (Voice over Internet Protocol). The technology and process, comprising of a group of standards, in which a telephone call is transmitted over the Internet VoLTE (Voice over Long-Term Evolution). A service in which IP telephony is served over an LTE (i.e., fourth-generation cellular) wireless network WebRTC (Web Real-Time Communication). A recent open standard protocol that provides interoperability among browsers for real-time communications such as voice, video, and peer-to-peer applications
ziffdavis.com
5 of 5