Glossary of Telecom Terms : O

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See Ordering and Billing Forum.


See Optical Carrier Level.


See Optical Carrier Level.


See Optical Carrier Level.


See Operating Company Number.


On-Line Service Provisioning (OLSP)
System that allows for online activating and provisioning of service orders.


The idle condition of Switched Access or a Telephone Exchange Service line.


On-the-Fly Switching
Refers to a method of Frame Switching where the switching device commences forwarding a frame after it has determined the destination port without waiting for the entire frame to have been received on the incoming port. Also known as cut-through switching.


Open End
The end of a Switched Access Service that transmits ringing and dial tone and receives address signaling.


Open Network Architecture (ONA)
The overall design of a carrier's basic network facilities and services to permit all users of the basic network, including enhanced service providers, to interconnect to basic network functions on an unbundled and "equal access" basis. ONA services include the following:


Open System Interconnection
The platform for EBTA.


Operating Company Number (OCN)
A four-character code assigned by the National Exchange Carrier Association (NECA) to any telecommunications provider. Specifically used to identify CLEC and Reseller usage data. Also known as Company Code.


Operating System Interconnection (OSI)
The platform for EBTA.


Operating Telephone Company (OTC)
A common carrier engaged in the provision of exchange access service.


Operations Support System (OSS)
Refers to systems (both Verizon systems and those of external vendors such as Telcordia) that provide operations services such as workforce management, trouble processing, dispatch, customer line records, testing, etc.


Operations Support Systems (OSS) Gateway
The interface that a CLEC and Reseller uses to access Verizon's Operations Support Systems. The gateway is the point where data can be exchanged between the CLEC or Reseller and Verizon. Access Ordering and Local Service Interface (LSI) are examples of an OSS Gateway.


Operator Assistance
A Verizon Wholesale service providing end users with dialing assistance or help completing a call. Learn more.


Operator Service Provider
Any common carrier that provides operator services.


Operator Service System
Equipment capable of processing certain kinds of traffic originating or terminating to an end office; this processing may take place either with or without an operator's assistance. Use of such equipment includes call rating and charge recording functions, operator assistance functions, coin control and collection functions, automatic or manual identification of calling line number, and verification of the busy/idle condition of subscriber lines.

Operator Services
Any of a variety of telephone services that need the assistance of an operator or an automated "operator" (that is, using interactive voice response technology and speech recognition). Such services include collect calls, third party billed calls and person-to-person calls.


Optical Carrier Level
A SONET term. A range of bandwidths as specified in a Telcordia Technologies (formerly Bellcore) document and associated ANSI standards. For example: Optical Carrier Level 1 (OC-1)--The optical signal that results from an STS-1 signal conversion. Optical Carrier level 3 (OC-3)--An optical carrier with three 51.84M bps multiplexed OC-1 circuit streams on an underlying SONET/SDH circuit. Optical Carrier Level 3-c (OC-3c)--An OC-3 circuit with the three OC-1 lines concatenated into a 155.52M bps circuit; used in ATM transmission. See ATM and OQS (Open Query System).


Optical Hubbing Service (OHS)
An Entrance Facility service offered through Verizon Wholesale. Learn more.


Order Process
The day-to-day placement of Verizon Wholesale orders with Verizon. It begins once a business relationship has been established (See Getting Started with Wholesale Access and Establish and Maintain Account for Local Services) and includes both placement of Pre-Order transactions and ASR/LSR Order requests. Compare with provisioning.


Order Samples
A collection of ordering scenarios for Access Service Requests (ASRs) and Local Service Requests (LSRs) for specific products and services. Order Samples detail specific forms and fields and can include support documentation such as USOC/ISOC guides, mapping guides, and product ordering guides.


Ordering and Billing Forum (OBF)
An industry forum sponsored by the by the Carrier Liaison Committee (CLC) of the Alliance for Telecommunications Industry Solutions (ATIS). The OBF sponsors several industry standards and guidelines, including the Local Service Ordering Guidelines and the Access Service Ordering Guidelines. In addition, it serves as a forum where service providers and customers can discuss billing, ordering, provisioning and other service-related issues and solutions.


Ordering Local Services
The Verizon Wholesale web page that provides all information related to ordering Local services. Includes process flows, links to related information, definitions, order samples; informally known at the Local Order Guide, or LOG. Learn more.


Originating Direction
The use of Access Service for the origination of calls from an End User premise to a customer premise.


OSI Reference Model
Seven-layer network architecture model of data communication protocols developed by ISO and CCITT. Each layer specifies particular network functions such as addressing, flow control, error control, encapsulation, and reliable message transfer.


OSS Change Management
A Verizon team; the single point of contact for the OSS Interface Change Management Process (CMP), by which the OSS Interface Change Management Agreement defines how interfaces will be introduced, retired or enhanced. This agreement contains provisioning for a CLEC Test Environment where advance testing of new releases and new entrant testing may occur, a bulletin process to alert the CLEC community to OSS fixes to production interfaces and monthly scheduled and interim meetings, as required. Learn more.


Other Changes and Credits
The section of the Verizon bill that contains charges/credits generally associated with Installation and Repair.


Other Common Carrier (OCC)
Telecommunication carriers providing long distance service. Also known as Interexchange Carriers.


Out-of-Band Signaling
An exchange access signaling feature which allows customers to exchange call control and signaling information over a communication path that is separate from the message path.


Out-of-Frame (OOF)
An Out-of-Frame condition occurs when a specified proportion of consecutive framing bits are in error.


Outside Plant
Includes facilities, equipment and other material connecting the Verizon central office building to the end user premise or another central office; for example, cable, poles, manholes, drop wires, etc.



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