Glossary of Telecom Terms : E

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E-911 Service
An emergency call service that routes 911 calls to a Public Safety Answering Point.


See Extended Area Service.


Earning Telephone Number Indicator
The auxiliary number under which charges are accrued.


See Electronic Bonding.


See Electronic Bonding Trouble Administration (EBTA).


See Exchange Carrier Code.


Echo Return Loss (ERL)
A frequency-weighted measure of return loss over the middle of the voiceband (approximately 560 to 1965 Hz) where talker echo is most annoying.


See Electronic Data Interchange.


A template used to capture and format order data into an EDI message. There is a different map for each pre-order transaction and each LSR order form. Pre-Order EDI maps are contained in the Verizon EDI Guide for Pre-Order Local Service Requests (Pre-Order LSR).


See Expanded Extended Loop.


See Exterior Gateway Protocol.


See Expanded Interconnection Service.


Electronic Bonding (EB)
An electronic interface that allows a local exchange carrier's (LEC's) customer to connect their Operations Support Systems (OSS) with the LEC's OSS in support of specific customer network management system, such as Trouble Administration.


Electronic Bonding Trouble Administration (EBTA)
An application-to-application Open System Interconnection (OSI) based system, which allows trouble report transactions to be exchanged between Verizon and its bonding partners in real time.


Electronic Commerce
A set of services which enable the secure exchange of electronic funds via the internet. Generally, E-Commerce is referred to in relation to websites that promote products and services for immediate sale.


Electronic Data Interchange (EDI)
Industry standard method of electronically exchanging data such as orders, invoices, etc. between two different locations or organizations.


Electronic Interface Format (EIF)
A standardized file format required by Verizon to communicate with DCAS.


Email (or E-Mail)
An abbreviation for electronic mail, which is a network service that allows users to send and receive messages via computer. The Internet and common message protocols makes it possible to send and receive email messages worldwide.


See Exchange Message Interface/Exchange Message Record.


End Office (EO)

  1. A central office to which a telephone end user is connected; the final central office before the end user's telephone.
  2. The central office trunking/switching entity where telephone loops are terminated for purposes of interconnection to each other and to the network.

End Office Connection (EOC)
The interconnection between a Verizon end office and another service provider's switching entity/Point of Interface, over which traffic may flow between the end office and its remotes, and the other service provider's switching entity/Point of Interface.


End Office Switch
A local exchange carrier switching system, where telephone exchange service customer station loops are terminated for purposes of interconnection to trunks. In the case of a Remote Switching Module, the term, End Office Switch, designates the combination of the Remote Switching Module and its host.


End User
Any customer of a telecommunications service that is not a carrier, except for the following exceptions:

  1. A carrier other than a telephone service provider is considered to be an "end user," when the carrier uses a telecommunications service for administrative purposes.
  2. A person or entity that offers telecommunications services exclusively as a Reseller is considered to be an "end user" if all resale transmissions offered by the reseller originate on the premises of the reseller.

Enhanced Service Provider
Provider of a broad range of computer applications that use the telecommunications network. These applications include information retrieval, database services, packet switching and others.


Enterprise Network
A geographically dispersed network under the auspices of one organization.


Entrance Facility
Point of interconnection between the local exchange carrier's (LEC) Rate Demarcation Point and the external carrier's Point of Presence (POP).


Entry Switch
The first telephone service provider location at which switching occurs on the terminating path of a call originating from the customer premises to the terminating end office. Also, the last telephone service provider location at which switching occurs. Also known as First Point of Switching.


See End Office Connection.


Equal Access
As defined by the Modified Final judgment, a uniform method by which Interexchange Carriers are accessed by end-users.


Erlang Forecast
An engineering formula for forecasting capacity for required telephone service provider facilities.


Error Codes
Alpha/Numeric codes used to identify and describe errors associated with the submission of Access Service Requests (ASRs) and Local Service Requests (LSRs).   Learn more (East)  (West).


Error Code LookUp
A tool enabling a view of the business rule field associated with a specific error code. Learn more.


Estimated Busy Hour Signaling Octets
Provides an estimate of busy hour signaling octets (a group of eight bits) for each Signal Transfer Point (STP) being connected with this request.


A 100-Mbps technology based on the 10BASE-T Ethernet CSMA/CD network access method to accommodate the operation of local area networks (LANs).


Ethernet Virtual Circuit (EVC)
Verizon's Ethernet Virtual Circuit (EVC) provides point-to-point connectivity between Ethernet TLS UNI circuits (UNI to UNI), and Ethernet TLS UNI circuits and NNI circuits (UNI to NNI). The EVC is available for connectivity between ERS UNI circuits only, in four service types (one for Standard, and three for Premier) and a multitude of speeds. Learn more


Ex Parte
Any communication addressing the merits of a particular proceeding (such as a judicial proceeding), which is made to decision-making personnel by other persons, where all parties to the proceedings are not present.


A Verizon Wholesale application for submitting Access Service Requests (ASRs) to Verizon via a batch process in Verizon South and Verizon West. Learn more.


A unit generally smaller than a LATA, established by the local exchange carrier (LEC) for the administration of communications service in a specified area (usually a city, town, or village and its environs). An exchange consists of one or more central offices together with the associated facilities used to provide communications services within that area. One or more designated exchanges comprise a given LATA.


Exchange Access
As defined in the Telecommunications Act of 1996, the offering of access to telephone exchange services or facilities for the purposes of the origination or termination of telephone toll service.


Exchange Access Signaling
The signaling system that is used by equal access end offices, to transmit originating information and address digits to the customer's premises, and verify receipt of these address digits. Features of this system include overlap outpulsing, identification of the type of call, identification of the ten-digit telephone number of the calling party, and acknowledgment with supervisory signals.


Exchange Carrier Code (ECC)
A four-character code assigned to CLECs by Telcordia Technologies. The Exchange Carrier Code and Company Code (assigned by NECA) identify the CLEC to the companies from whom they buy (or lease) telephone numbers, dial tone, facilities, etc. Also known as AECN .


Exchange Message Interface/Exchange Message Record(EMI/EMR)
The standard format used for exchange of telecommunications message information among Local Exchange Carriers (LEC) for billable, non-billable, sample, settlement and study data. EMR format is contained in Telcordia Technologies Publication BR-010-200-010 CRIS Exchange Messaging.


Exchange Service
All basic access line services, or any other services offered to end users which provide end users with a telephonic connection to, and a unique telephone number address on, the Public Switched Telephone Network (PSTN), and which enable such end users to place or receive calls to all other stations on the PSTN.


Expanded Extended Loop
A Verizon Wholesale offering that provides a combination of dedicated unbundled loops and unbundled interoffice transport, and includes multiplexing (where required), and loops, which are installed by Verizon at the Local Service Provider's (LSP) request. Learn more.


Expanded Interconnection Service (EIS)
A service that provides interconnecting carriers with the capability to terminate basic fiber optic transmission facilities, including optical terminating equipment and multiplexers, at Verizon's wire centers and access tandems and interconnect those facilities with the facilities of Verizon.


Verizon customer care, ordering and billing system for Maryland, Delaware, and West Virginia.


Extended Area Service (EAS)
Refers to a larger than normal local telephone calling area, under specialized payment plans.


Extended Dedicated Trunk Port
A Verizon Wholesale UNE service offering that provides the CLEC with the ability to custom route its Unbundled Line Port customers' traffic off the Verizon Unbundled Local Switch to dedicated trunks and transport connected to another switch location in the same LATA. Learn more.


Extended Superframe (ESF)
A type of DS1 framing format that uses a framing bit of twenty-four consecutive frames to provide a 2 kilobits per second framing pattern sequence, a 4 kilobits per second data link, and a 2 kilobits per second cyclic redundancy check channel.


Exterior Gateway Protocol (EGP)
The TCP/IP-based service by which gateways exchange information about which systems they can reach. Generally, an exterior gateway protocol is any internetworking protocol for passing routing information between autonomous systems.



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