Glossary of Terms
Carrier Ethernet Terms and Terminlogy
The following is the most up-to-date and comprehensive available glossary of terms used in Carrier Ethernet Specifications MEF 1 to MEF 25.
| Term | Description | MEF Specification |
| 3GPP | 3rd Generation Partnership Project | 22 |
| AAL1 | ATM Adaptation Layer 1 | 8, 11 |
| Access Link | A link that represents connectivity to External Reference Points of the MEN | 2 |
| ADM | Add Drop Multiplexer | 2 |
| AIS | Alarm Indication Signal | 3, 8, 11,20, 25 |
| Alarm Status | Indicates the occurrence of an abnormal condition. Values for alarm status include: critical, major, minor, indeterminate, warning, pending, and cleared | 15 |
| All to One Bundling | A UNI attribute in which all CE-VLAN IDs are associated with a single EVC | 6, 6.1, 19, 7, 9, 10, 10.1, 14, 15 |
| ALNP | Aggregated Line and Node Protection | 2 |
| ANSI | American National Standards Institute | 3, 8, 11 |
| APCP | Application Protection Constraint Policy | 2 |
| APP | Application Layer, Application Services Layer | 12, 17, 4 |
| APS | Automatic Protection Switch, Automatic Protection Switching | 2, 3 |
| ATM | Asynchronous Transfer Mode | 4, 8, 11 |
| Availability Performance | A measure of the percentage of time that a service is useable. | 10.1 |
| Bandwidth Profile | A characterization of ingress Service Frame arrival times and lengths at a reference point and a specification of the disposition of each Service Frame based on its level of compliance with the Bandwidth Profile. In this document the reference point is the UNI | 19, 6, 6.1, 10, 14, 15, 7, 9 |
| Bandwidth profile per CoS ID | A UNI service attribute | 6, 6.1 |
| Bandwidth profile per EVC | A UNI service attribute | 6, 6.1 |
| Bandwidth profile per ingress UNI | A UNI service attribute | 6, 6.1 |
| BBER | Background Block Error Ratio | 3 |
| BER | Bit Error Rate, Bit Error Ratio | 2, 3 |
| BLSR | Bi-directional Line Switched Ring, Bi-directional Line Switching Redundancy | 3, 2 |
| BPDU | Bridge Protocol Data Unit | 2 |
| Broadcast Service Frame | A Service Frame that has a broadcast destination MAC address. | 7, 15, 19, 10, 10.1, 14 |
| Broadcast Service Frame Delivery | An EVC service attribute | 6, 6.1 |
| Bundling | A UNI attribute in which more than one CE-VLAN ID can be associated with an EVC | 19, 10, 9, 10.1, 14, 7, 15, 6, 6.1 |
| BW | Bandwidth | 20 |
| BWP | Bandwidth Profile | 12 |
| Carrier Ethernet | Carrier Ethernet is a ubiquitous, standardized, carrier-class network and service defined by five attributes that distinguish it from familiar LAN based Ethernet. These are Standardized Services, Scalability, Reliability, Quality of Service and Service Management | |
| CAS | Channel Associated Signaling | 3, 8, 11 |
| CBS | Committed Burst Size | 6, 6.1, 7, 8, 10, 10.1, 11, 13, 14, 15, 19 |
| CCM | Connectivity Check Message | 20, 25 |
| CCS | Common Channel Signaling | 3, 8, 11 |
| CE | Customer Equipment, Carrier Ethernet, Customer Edge, Circuit Emulation | 2, 3, 4, 6, 6.1, 7, 8, 9, 10, 10.1, 11, 12, 14, 15, 16, 19,20,22, 24 |
| CEN | Carrier Ethernet Network. Within the context of the MEF specifications, Metro Ethernet and Carrier Ethernet or MENs and CENs can be used interchangeably | 2, 4, 6, 6.1, 7, 8, 9, 11, 12, 15, 16, 3, 17,22, 23 |
| CES | Circuit Emulation Services | 2, 7, 15, 3, 8, 11 |
| CESoETH | Circuit Emulation Services over Ethernet | 8, 11 |
| CE-VLAN CoS | Customer Edge VLAN CoS. The user_priority bits in the IEEE 802.1Q Tag in a Service Frame that is either tagged or priority tagged. | 6, 6.1, 10, 10.1, 14, 19, 7, 15 |
| CE-VLAN CoS Preservation | An EVC service attribute | 6, 6.1 |
| CE-VLAN ID | The identifier derivable from the content of a Service Frame that allows the Service Frame to be associated with an EVC at the UNI. Customer Edge VLAN ID. The identity of the VLANs on the Ethernet port of the customer equipment that is attached to the UNI. | 13, 10, 10.1, 14, 19, 15, 6, 6.1, 7, 9 |
| CE-VLAN ID / EVC Map | A UNI service attribute | 6, 6.1 |
| CE-VLAN ID Preservation | An EVC attribute in which the CE-VLAN ID of an egress Service Frame is identical in value to the CE-VLAN ID of the corresponding ingress Service Frame | 19, 6, 6.1, 7, 10, 10.1, 14, 15 |
| CE-VLAN ID/EVC Map | An association of CE-VLAN IDs and EVCs at a UNI. | 7, 15, 19, 9. 10, 10.1, 14 |
| CE-VLAN Tag | Customer Edge VLAN Tag. The IEEE 802.1Q Tag in a tagged Service Frame. | 6, 6.1, 7, 9, 10, 10.1, 14, 19, 15 |
| CE-VLAN tag preservation | A set of EVC service attributes | 6, 6.1 |
| CF | Coupling Flag | 6, 6.1, 8, 10, 10.1, 11, 14, 19, 15 |
| CFI | Canonical Format Indicator | 12 |
| CFM | Connectivity Fault Management | 20 |
| CI | Characteristic Information | 4, 12 |
| CIR | Committed Information Rate | 2, 7, 8, 10, 10.1, 11, 13, 14, 15, 19, 6, 6.1 |
| CIR-compliant | Service frames that are compliant with the CIR of the bandwidth profile. CIR-compliant service frames are colored green. | 7, 15 |
| Circuit Emulation Service | A service that transports TDM-based traffic over a Metro Ethernet Network. | 7, 15 |
| Class of Service | A set of Service Frames that have a commitment from the Service Provider to receive a particular level of performance. | 19, 7, 9, 10, 10.1, 14, 15, 6, 6.1 |
| Class of Service Identifier | Information derivable from a) the EVC to which the Service Frame is mapped, b) the combination of the EVC to which the Service Frame is mapped and a set of one or more CE-VLAN CoS values, c) the combination of the EVC to which the Service Frame is mapped and a set of one or more DSCP values, or d) the combination of the EVC to which the Service Frame is mapped and a set of one or more tunneled Layer 2 Control Protocols. | 9, 19, 10, 14, 10.1 |
| Class of Service Performance | A set of EVC-related service attributes | 6, 6.1 |
| CLE | Customer Located Equipment | 17 |
| CLI | Command Line Interface | 15 |
| CM | Color Mode, Configuration Management | 6, 6.1, 10, 10.1, 14, 19, 15 |
| Color Mode | CM is a Bandwidth Profile parameter. The Color Mode parameter indicates whether the color-aware or color-blind property is employed by the Bandwidth Profile. It takes a value of “color-blind” or “color-aware” only. | 6, 6.1, 19, 10, 10.1, 14 |
| Color-aware | A Bandwidth Profile property where a pre-determined level of Bandwidth Profile compliance for each Service Frame is taken into account when determining the level of compliance for each Service Frame A traffic management capability used to determine whether traffic is conformant or non-conformant to a bandwidth profile based on different CoS ID values. | 19, 10, 10.1, 14, 7, 15 |
| Color-blind | A Bandwidth Profile property where a pre-determined level of Bandwidth Profile compliance for each Service Frame, if present, is ignored when determining the level of compliance for each Service Frame | 19, 10, 10.1, 14, 7, 15 |
| Color Forwarding | An OVC attribute defining the relationship between the Color of an egress ENNI Frame and the Color of the corresponding ingress ENNI Frame or Service Frame. | ENNI |
| Committed Burst Size | CBS is a Bandwidth Profile parameter. It limits the maximum number of bytes available for a burst of Service Frames sent at the UNI speed to remain CIR-conformant. It defines the average rate in bits/s of ingress Service Frames up to which the network delivers Service Frames and meets the performance objectives defined by the CoS Service Attribute | 6, 6.1, 19, 10, 14, 10.1, 7, 15 |
| Committed Information Rate | CIR is a Bandwidth Profile parameter. It defines the average rate in bits/s of ingress Service Frames up to which the network delivers Service Frames and meets the performance objectives defined by the CoS Service Attribute. A Bandwidth Profile property where a pre-determined level of Bandwidth Profile compliance for each Service Frame, if present, is ignored when determining the level of compliance for each Service Frame | 6, 6.1, 19, 10, 14, 15, 10.1, 7 |
| CoS | Class of Service | 6, 6.1, 7, 8, 10.1, 11, 12, 15, 17, 20, 22, 23, 25 |
| CoS ID | Class of Service Identifier | 20 |
| CoS ID/ CoS Identifier | Class of Service Identifier | 12 |
| Coupling Flag | CF is a Bandwidth Profile parameter. The Coupling Flag allows the choice between two modes of operation of the rate enforcement algorithm. It takes a value of 0 or 1 only. | 6, 6.1, 10.1, 19, 15, 10, 14, 23 |
| CPE | Customer Premise Equipment | 17 |
| CR | Clock Recovery. | 3 |
| CRC | Cyclic Redundancy Check | 2, 3, 8, 11 |
| CSPF | Constriant-based Shortest Path First | 2 |
| CUET | Customer Unit Edge Terminal | 3 |
| Current Problem List | Identifies the current existing problems (probable cause), with severity for an entity | 15 |
| Customer | The organization purchasing and/or using Ethernet Services. Alternate term: Subscriber | 7, 15 |
| Customer Edge | Equipment on the Subscriber side of the UNI | 6, 6.1, 7, 9, 15, 15, 19, 10, 10.1, 14, 23 |
| Customer Edge VLAN CoS | The Priority Code Point bits in the IEEE 802.1Q Customer VLAN Tag in a Service Frame that is either tagged or priority tagged. | 6, 6.1, 7, 9,, 15, 10.1, 19, 14, 10, 23 |
| Customer Edge VLAN ID | The identifier derivable from the content of a Service Frame that allows the Service Frame to be associated with an EVC at the UNI. | 6, 6.1, 19, 10, 10.1, 14, 7, 15, 23 |
| Customer Edge VLAN Tag | The IEEE 802.1Q Tag in a tagged Service Frame. When present, it contains the customer Edge VLAN ID and the Customer Edge VLAN CoS. | 6, 6.1, 9, 10.1, 19, 10, 14, 7, 15, 23 |
| C-VLAN | Customer VLAN | 12 |
| DA | Destination Address | 20 |
| Data Service Frame | A Service Frame that is Unicast, Multicast, or Broadcast. | 10.1 |
| DCE | Data Circuit-terminating Equipment | 2 |
| DEI | Discard Eligible Indicator | 23 |
| DI | Data Instance | 16, 24 |
| DLCI | Data Link Connection Identifier. A number attached to a data frame that identifies the PVC for the data frame. | 6, 6.1 |
| Down | MEP A MEP residing in a Bridge that receives CFM PDUs from, and transmits | 25 |
| Down-MEP | A MEP in an 802.1 Bridge that sends frames away from the Bridge Relay Entity; see [IEEE 802.1ag] | 20 |
| DP | Discard Priority | 12 |
| DSL | Digital Subscriber Line | 2 |
| DSTM | Derived System Timing Mode. The IWF system clock is derived from the incoming Ethernet frames. | 3 |
| DTE | Data Terminal Equipment | 21 |
| DTM | Derived Timing Mode The recovered service clock is derived from the incoming Ethernet frames.. | 3 |
| Dual Rate Bandwidth Profile | A bandwidth profile that specifies both a CIR/CBS and EIR/EBS. | 7, 15 |
| DUT | Device Under Test | 18 |
| EAF | ETH Adaptation Function | 12 |
| EBS | Excess Burst Size | 7, 8, 10, 10.1, 11, 13, 14, 15, 19, 23 |
| ECDX | Emulated Circuit De/Multiplexing Function | 3, 8, 11 |
| ECF | ETH Connection Function, Ethernet Connection Function | 12, 2 |
| ECID | Emulated Circuit Identifier | 3, 8, 11 |
| ECT | Ethernet Connectionless Trail | 12 |
| EEPP | End-to-End Path Protection | 2 |
| EETF | ETH EVC Termination Function | 12 |
| EFCF | ETH Flow Conditioning Function | 12 |
| EFD | ETH Flow Domain | 12 |
| EFM | Ethernet First Mile | 2 |
| EFT | Ethernet Flow Termination | 3 |
| EFTF | Ethernet Flow Termination Function | 8, 11, 12 |
| Egress Bandwidth Profile | A service attribute that specifies the length and arrival time characteristics of egress Service Frames at the egress UNI. | 10.1, 23 |
| Egress Frame | A service frame sent from the Service Provider network to the CE. | 7 |
| Egress Service Frame | A service frame sent from the Service Provider network to the CE. | 9, 19, 10, 10.1, 14, 15, 6, 6.1, 23 |
| EI | External Interface | 23 |
| EIR | Excess Information Rate | 2, 6, 6.1, 7, 8, 10, 10.1, 11, 13, 14, 15, 19, 23 |
| EIR-compliant | Service frames that are compliant with the EIR of the bandwidth profile. EIR-compliant service frames may be colored green or yellow depending upon whether they are CIR-compliant or not, respectively. | 7, 15 |
| E-LAN | An Ethernet service type that is based on a Multipoint-to-Multipoint EVC | 6, 6.1, 2, 9, 20 |
| E-LAN Service | Ethernet LAN Service | 10, 10.1, 14, 19, 23 |
| E-Line | An Ethernet service type that is based on a Point-to-Point EVC | 6, 6.1, 2, 3, 8, 11, 20 |
| E-Line Service | An Ethernet service type that is based on a Point-to-Point EVC. | 23 |
| E-LMI | Ethernet Layer Management Interface | 15, 17,20, 24 |
| EMS | Element Management System | 25, 17 |
| ENNI | External Network to Network Interface | 15, 15, 17, 23 |
| ENNI Frame | The first bit of the Destination Address to the last bit of the Frame Check Sequence of the Ethernet Frame transmitted across the ENNI. | ENNI |
| ENNI MTU | MTU of an ENNI frame at the ENNI | ENNI |
| ENNI-Ni | The functional element of the ENNI separately administered by the Operator of the ith Operator MEN. | ENNI |
| EoS | Ethernet over Sonet | 2 |
| EoSONET | Ethernet over SONET | 17 |
| EPCF | ETH Provider Conditioning Function | 12 |
| EPL | Ethernet Private Line | 6, 6.1, 8, 11,22, 23 |
| EP-LAN | Ethernet Private LAN | 22 |
| EP-Tree | Ethernet Private Tree | 22 |
| ES | Errored Second | 3, 8, 11 |
| ESCF | ETH Subscriber Conditioning Function. Ethernet Subscriber Conditioning Function | 12, 17 |
| ESD | Ethernet Services Definition | 4 |
| ESF | Extended Super Frame | 3, 8, 11 |
| ESM | Ethernet Services Model | 4 |
| ESR | Errored Second Ratio | 3, 8, 11 |
| ETH | Ethernet Services Layer | 2, 4, 12, 17 |
| ETH FPP | An Ethernet Flow Point Pool that represents an Ethernet UNI or ENNI. | 15 |
| ETH-AIS | Ethernet Alarm Indication Signal | 25 |
| Ethernet LAN Service | An Ethernet Service Type distinguished by its use of a Multipoint-to-Multipoint EVC | 19, 10, 10.1, 14, 9 |
| Ethernet Line Service | An Ethernet Service Type distinguished by its use of a Point-to-Point EVC | 19, 10, 10.1, 14 |
| Ethernet Virtual Connection | An association of two or more UNIs that limits the exchange of frames to UNIs in the Ethernet Virtual Connection (EVC) | 6, 6.1, 7, 15, 19, 9, 10, 10.1, 14, 23 |
| EtherType | Ethernet Length/Type | 12 |
| ETH-trail | An ETH-trail is an “ETH-layer entity” responsible for the transfer of information from the input of a trail termination source to the output of a trail termination sink. | 2 |
| E-Tree | An Ethernet service type that is based on a Rooted-Multipoint EVC. | 6.1 |
| E-Tree Service | An Ethernet service type that is based on a Rooted-Multipoint EVC. | 23 |
| ETY | Ethernet Physical Layer | 7, 15 |
| EVC | Ethernet Virtual Connection. An association of two or more UNIs that limits the exchange of frames to UNIs in the Ethernet Virtual Connection | 3, 2, 4, 6, 6.1, 7, 8, 9, 10, 10.1, 11, 12, 14, 15, 16, 17, 19, 13, ,20,22,23,24, 25 |
| EVC ID | The Identifier for an EVC | 20 |
| EVC Maximum Transmission Unit Size | The maximum sized Service Frame allowed for an EVC. | 10.1 |
| EVC MTU Size | The maximum sized Service Frame allowed for an EVC. | 6.1, 1 0.1 |
| EVC-MA | Ethernet Virtual Connection Maintenance Association | 25 |
| EVPL | Ethernet Virtual Private Line | 6, 6.1, 8, 11,22, 23 |
| EVP-LAN | Ethernet Virtual Private LAN | 22, 23 |
| EVP-Tree | Ethernet Virtual Private Tree | 22 |
| Excess Burst Size | EBS is a Bandwidth Profile parameter. It limits the maximum number of bytes available for a burst of ingress Service Frames sent at the UNI speed to remain EIR-conformant | 6, 6.1, 19, 10, 14, 15, 10.1, 7, 23 |
| Excess Information Rate | EIR is a Bandwidth Profile parameter. It defines the average rate in bits/s of ingress Service Frames up to which the network may deliver Service Frames without any performance objectives. The rate up to which the network will attempt to deliver Ethernet service frames before they are discarded. | 6, 6.1, 19, 10, 14, 15, 10.1, 7, 23 |
| External Interface | Defined physical demarcation point between the MEN and outside, across which Ethernet Service Frames are presented. | 23 |
| FCS | Frame Check Sequence | 8, 11, 12 |
| FD | Frame Delay | 10, 10.1, 14, 15, 19,22, 23 |
| FDL | Facility Data Link | 3, 8, 11 |
| FDV | Frame Delay Variation (Often misquoted as Jitter) | 10, 10.1, 14, 17, 19,22, 23 |
| FDX | Full Duplex | 6, 6.1, 7, 15 |
| FE | Functional Element | 4 |
| FER | Frame Error Ratio | 3, 8, 11 |
| FLR | Frame Loss Ratio | 10, 10.1, 14, 17, 19,22, 23 |
| FM | Fault Management | 25 |
| FPP | Flow Point Pool | 12 |
| Frame | Short for Ethernet Frame | 6, 6.1, 19, 7, 10, 10.1, 13, 14, 15, 23 |
| Frame Delay | The time required to transmit a Service Frame from ingress UNI to egress UNI. | 6, 6.1, 10.1, 19, 10, 14, 15, 23 |
| Frame Delay Performance | A measure of the delays experienced by Service Frames belonging to the same CoS instance | 10, 10.1, 14, 15, 19, 23 |
| Frame Delay Variation | The difference in delay of two Service Frames | 6, 6.1, 19, 10, 10.1, 14, 15, 23 |
| Frame Delay Variation Performance | A measure of the variation in the delays experienced by different Service Frames belonging to the same CoS instance. | 10, 10.1, 14, 15, 19, 23 |
| Frame Loss Ratio Performance | Frame Loss Ratio is a measure of the number of lost frames between the ingress UNI and the egress UNI. Frame Loss Ratio is expressed as a percentage. | 10.1, 19, 10, 14, 15, 23 |
| Frame | Short for Ethernet Frame | 9 |
| GARP | Generic Attribute Registration Protocol | 2, 20 |
| GbE | Gigabit Ethernet | 4 |
| GIWF | Generic Inter-working Function | 22 |
| Global Interconnect | The totality of interconnected autonomous Carrier Ethernet networks to enable standardized and streamlined delivery of MEF-certified Carrier Ethernet services with end-to-end Class of Service, management and protection, worldwide | |
| GRE | Generic Routing Encapsulation | 2 |
| HDX | Half Duplex | 7, 15 |
| HOVC | Higher Order Virtual Container | 3 |
| IA | Implementation Agreement | 3, 8, 11, 20 |
| IE | Information Element | 15 |
| IEEE | Institute of Electrical and Electronics Engineers | 4, 8, 11 |
| IETF | Internet Engineering Task Force | 2, 3, 8, 11, 16 |
| IGP | Interior Gateway Protocol | 2 |
| Ingress Bandwidth Profile | A characterization of ingress Service Frame arrival times and lengths at the ingress UNI and a specification of disposition of each Service Frame based on its level of compliance with the characterization. | 10.1, 23 |
| Ingress Frame | A service frame sent from the CE to the Service Provider network. | 7, 15 |
| Ingress Service Frame | A Service Frame sent from the CE into the Service Provider network | 19, 10, 10.1, 14, 6, 6.1, 23 |
| Ingress Service Frame | A Service Frame sent from the CE into the Service Provider network. | 9 |
| Ingress | The direction from the CE into the Service Provider network. | 13 |
| I-NNI | Internal NNI | 17 |
| ITU | International Telecommunication Union | 2, 4, 16 |
| ITU-T | International Telecommunication Union – Telecommunication standardization sector | 3, 8, 11 |
| IWF | Interworking Function | 4, 3, 8, 11 |
| L1 | Layer One | 4 |
| L2 | Layer Two | 4 |
| L2+ | Layer(s) above L2 | 4 |
| L2CP | Layer Two Control Protocols | 12, 20 |
| LACP | Link Aggregation Control Protocol | 2, 20 |
| LAG | Link Aggregation Group | 2, 2, 20 |
| LAN | Local Area network | 2, 4, 12 |
| LANE | ATM LAN Emulation | 17 |
| Layer 2 Control Protocol Service Frame | A Service Frame that is used for Layer 2 control, e.g., Spanning Tree Protocol. | 23, 6, 6.1, 19, 9, 10, 10.1, 13, 14 |
| Layer 2 Control Protocol Service Frame Delivery | The process by which a Layer 2 Control Protocol Service Frame is passed through the Service Provider network switches without being processed by those switches and delivered to the proper UNI(s). | 6, 6.1 |
| Layer 2 Control protocol Tunneling | The process by which a Layer 2 Control protocol Service Frame is passed through the Service Provider network without being processed and delivered unchanged to the proper UNI(s). | 9, 19, 10, 10.1, 14, 23 |
| LB | Loop Back | 20 |
| LBM | Loopback Message | 20, 25 |
| LBR | Loopback Reply | 20, 25 |
| Link | An ETH link or TRAN link | 2 |
| Link OAM | OAM specific to a single link as per clause 57 of [IEEE 802.3] | 20 |
| LLC | Logical Link Control | 12 |
| LOF | Loss of Frame, Loss of Frame Alignment | 2, 8, 11 |
| LOFS | Loss of Frames State | 8, 11 |
| LOH | Line OverHead | 3 |
| LOPS | Loss Of Packet Synchronization | 3 |
| LOS | Loss of Signal | 2, 3, 8, 11 |
| LOVC | Lower Order Virtual Container | 3 |
| LSP | Label Switched Path | 2 |
| LSR | Label Switched Router | 2 |
| LTE | Line Termination Equipment | 3 |
| MA | Maintenance Association | 25 |
| MAC | Media Access Control | 2, 4, 12, 16, 17, 8, 11,25, 24 |
| MAID | Maintenance Association Identifier | 25 |
| Mapper | A device or logic that implements a mapping function | 3 |
| Mapping | The process of associating each bit transmitted by the service into the SDH/SONET payload structure that carries the service. For example, mapping a DS1 service into SONET VT-1.5 / SDH VC-11 associate each bit of the DS1 with a location in the VT-1.5/VC-11 | 3 |
| Maximum number of EVCs | A UNI service attribute ? | 6, 6.1 |
| Maximum Number of UNIs | The maximum number of UNIs that may be in an EVC. | 10.1 |
| MCF | MAC Convergence Function | 12 |
| MD | Maintenance Domain | 20,25, 25 |
| ME | Maintenance Entity | 17,20, 25 |
| Mean time to restore | The mean time from when a service is unavailable to the time it becomes available again | 2 |
| MEF | Metro Ethernet Forum | 2, 4, 16 |
| MEG | A Maintenance Entity Group (MEG) consists of the MEs that belong to the same service inside a common OAM domain. | 17,20, 25,ENNI |
| MEG-Level | Maintenance Entity Group Level | 20 |
| MEN | Metro Ethernet Network. Within the context of the MEF specifications, Metro Ethernet and Carrier Ethernet or MENs and CENs can be used interchangeably | 2, 4, 6, 6.1, 7, 8, 9, 11, 12, 15, 16, 3, 17,22, 23 |
| MEN-bound IWF | The IWF receiving TDM data from the customer’s TDM-based equipment, and forwarding this data in the form of Ethernet frames into the MEN. | 8, 11 |
| ME-NE | Metro Ethernet Network Element | 15 |
| MEP | A MEG End Point (MEP) is a provisioned OAM reference point which can initiate and terminate proactive OAM frames. A MEP can also initiate and react to diagnostic OAM frames. | 17,20, 25 |
| MEP ID | Maintenance Entity End Point Identification | 20 |
| Metro Ethernet Network | The Service Provider’s network providing Ethernet services | 6, 6.1, 7, 15, 23 |
| Metro Ethernet Network Element | A Network Element supporting Metro Ethernet services | 15 |
| MIB | Management Information Base | 3, 8, 11 |
| MIF | MAC Independent Function | 12 |
| MIP | MEG Intermediate Point | 17, 20 |
| MNU | Maximum Number of UNIs | 10.1 |
| MP | Maintenance Point. One of either a MEP or a MIP | 25 |
| MPLS | Multi Protocol Label Switching | 4, 2, 17 |
| MRTIE | Maximum Relative Time Interval Error | 18 |
| MTTR | Mean Time To Restore | 7, 15 |
| MTU | Maximum Transmission Unit | 6.1,20,22, 25 |
| MTU size | The maximum sized Service Frame allowed for an Ethernet service. | 6.1 |
| Multicast Service Frame | A Service Frame that has a multicast destination MAC address | 19, 7, 10, 9, 10.1, 13, 14, 15 |
| Multicast Service Frame Delivery | An EVC service attribute | 6, 6.1 |
| Multiplex | Transmit one or more channels over a single channel | 3 |
| Multipoint EVC | An EVC with two or more UNIs. A Multipoint-to-Multipoint EVC with two UNIs is different from a Point-to-Point EVC because one or more additional UNIs can be added to it. | 13 |
| Multipoint-to-Multipoint | An EVC with two or more UNIs. A Multipoint-to-Multipoint EVC with two UNIs is different from a Point-to-Point EVC because one or more additional UNIs can be added to it. | 7, 15 |
| Multipoint-to-Multipoint EVC | An EVC with two or more UNIs. A Multipoint-to-Multipoint EVC with two UNIs is different from a Point-to-Point EVC because one or more additional UNIs can be added to it. | 6, 6.1, 9, 19, 10, 10.1, 14, 23 |
| N/A | Not Applicable | 6, 6.1, 23 |
| N/S | Not Specified | 6, 6.1, 7, 15,22, 23 |
| NDD | Network Demarcation Device | 17 |
| NE | Network Element | 2, 4, 12, 17, 3,20, 25 |
|
Network Operator |
The Administrative Entity of a MEN. |
4 |
| NI- | Network Interworking (e.g., NI-NNI) | 4 |
| NI-NNI | Network Interworking NNI | 17 |
| NMS | Network Management System | 17, 25 |
| NNI | Network to Network Interface | 3, 12, 17, 4 |
| Node | A Provider owned network element | 2 |
| NT | Network Termination | 4 |
| NTP | Network Time Protocol | 22 |
| OAM | Operations, Administration and Maintenance | 2, 16, 17,20,21,25,25, 24 |
| OAMPDU | Operation Administration and maintenance protocol data unit | 21 |
| Operator | A carrier that administers a particular MEN or domain. If the Operator also provides the service to the Subscriber they are also the Service Provider | 23 |
| Operator-MA | Operator Maintenance Association | 25 |
| OTN | Optical Transport Network | 4 |
| OVC | Operator Virtual Connection | ENNI |
| OVC End Point | An OVC End Point is an association of an OVC with a specific External Interface i.e., UNI, ENNI. | ENNI |
| OVC ID | A Operator Ethernet Virtual_Connection_ID is a string that is unique among all OVCs in the Operator MEN | ENNI |
| P2P | Point-to-Point | 25 |
| Path | A succession of interconnected links at a specific (ETH or TRANS) layer | 2 |
| PCP | Priority Code Point | 22 |
| PCS | Physical Coding Sub-layer | 12 |
| PDH | Plesiochronous Digital Hierarchy. PDH refers to the DS1/DS2/DS3 and E1/E3/E4 family of signals as defined by ITU-T and ATIS. | 4, 3, 8, 11, 22 |
| PDU | Protocol Data Unit | 8, 11, 12,20, 25 |
| PE | Provider Edge | 2, 3, 4, 12 |
| PEC | Packet based Equipment Clocks | 22 |
| PICS | Protocol implementation conformance statement | 21 |
| PLL | Phase Locked Loop | 3 |
| Pointer | A part of the SDH/SONET overhead that locates a floating payload structure. Frequency differences between SDH/SONET network elements or between the payload and the SDH/SONET equipment can be accommodated by adjusting the pointer value. | 3 |
| Point-to-Point EVC | An EVC with exactly 2 UNIs. | 6, 6.1, 9, 19, 7, 10, 10.1, 13, 14, 15, 23 |
| PRBS | Pseudo-Random Binary Sequence | 18 |
| PRM | Protection Reference Model | 2 |
| Protection merge point | A point in which the protection path traffic is either merged back onto the working path or passed on to the higher layer protocols (used in , called ‘tail-end switch’ in SONET/SDH). | 2 |
| PRS | Primary Reference Source | 3 |
| PSTN | Public Switched Telephone Network | 3 |
| PT | Polling Timer | 24 |
| PTP | Precision Time Protocol | 22 |
| P-VLAN | Provider VLAN | 12 |
| PVT | Polling Verification Timer | 24 |
| PW | Pseudo Wire | 17 |
| PWE3 | Pseudo-Wire Emulation Edge to Edge (an IETF working group) | 3, 8, 11 |
| QoS | Quality of Service | 2 |
| RAN | Radio Access Network | 22 |
| RAN BS | RAN Base Station | 22 |
| RAN CE | RAN Customer Edge | 22 |
| RAN NC | RAN Network Controller | 22 |
| RDI | Remote Defect Indication | 3, 8, 11,20, 25 |
| RNC | Radio Network Controller | 22 |
| Rooted-Multipoint | 'MEF Point to Multipoint service; see [MEF 10.1] | 20 |
| Rooted-Multipoint EVC | A multipoint EVC in which each UNI is designated as either a Root or a Leaf. Ingress Service Frames at a Root UNI can be delivered to one or more of any of the other UNIs in the EVC. Ingress Service Frames at a Leaf UNI can only be delivered to one or more Root UNIs in the EVC. | 10.1, 23 |
| RPR | Resilient Packet Ring | 2, 4 |
| RSTP | Rapid Spanning Tree Protocol | 2 |
| RTP | Real-time Transport Protocol (an IETF protocol, described in RFC 3550) | 8, 11 |
| Scheduled Downtime | A time interval agreed upon by both the Subscriber and Service Provider during which a service may be disabled by the Service Provider. | 10.1 |
| SDH | Synchronous Digital Hierarchy | 2, 3, 4 |
| Segment | A connected subset of the trail | 2 |
| Service Frame | An Ethernet frame transmitted across the UNI toward the Service Provider or an Ethernet frame transmitted across the UNI toward the Subscriber. | 6, 6.1, 7, 9, 19, 10, 10.1, 13, 14, 15, 7, 15,21, 23 |
| Service Frame Delivery | A set of EVC service attributes | 6, 6.1 |
| Service Level Agreement | The contract between the Subscriber and Service Provider specifying the agreed to service level commitments and related business agreements. | 6, 6.1, 19, 10, 10.1, 14, 15, 7, 23 |
| Service Level Specification | The technical specification of the service being offered by the Service Provider to the Subscriber | 6, 6.1, 7, 15, 19, 10, 10.1, 14, 23 |
| Service Multiplexing | A UNI attribute in which the UNI can be in more than one EVC instance | 7, 9, 15, 13, 6, 6.1, 19, 10, 10.1, 14 |
| Service OAM | Service OAM is OAM used to monitor an individual Service; see [ITU-T Y.1731] and [IEEE 802.1ag] | 20 |
| Service Provider | The organization providing Ethernet Service(s) | 9, 19, 10, 10.1, 13, 14, 6, 6.1, 15, 7, 23 |
| SES | Severely Errored Second | 3 |
| SESR | Severely Errored Second Ratio | 3 |
| SF | Super Frame | 3, 8, 11 |
| SI- | Service Interworking (e.g., SI-NNI) | 4 |
| Single Rate Service | A service that only specifies a CIR/CBS and no EIR/EBS. | 7 |
| SI-NNI | Service Interworking NNI | 17 |
| SLA | Service Level Agreement | 22,23, 2, 3, 6, 6.1, 7, 10, 10.1, 14, 15, 17, 19 |
| SLS | Service Level Specification | 2, 3, 6, 6.1, 7, 10, 10.1, 14, 15, 17, 19, 23 |
| SNI | Service Node Interface | 4, 15, 17 |
| SOAM | Service Operations, Administration, and Maintenance | 25 |
| SONET | Synchronous Optical Network | 2, 3, 4 |
| SRLG | Shared Risk Link Group | 2 |
| SSM | Synchronization Status Message | 3 |
| SSRC | Synchronization Source (a field within the RTP protocol, RFC 3550) | 8, 11 |
| S-Tag | Service VLAN Tag. | 23 |
| STP | Spanning Tree Protocol | 2 |
| Structure-agnostic | Structure-agnostic emulation is the transport of unstructured TDM, or of structured TDM when the structure is completely disregarded by the transport mechanism. | 8, 11 |
| Structure-aware | Structure-aware emulation is the transport of structured TDM taking at least some level of the structure into account. | 8, 11 |
| Structure-indicated | Encapsulation utilized for Structure-Aware TDM transport where TDM structure boundaries are indicated by pointers | 8, 11 |
| Structure-locked | Encapsulation utilized for Structure-Aware TDM transport where TDM structure boundaries are indicated by packet payload boundaries | 8, 11 |
| Subscriber | The organization or customer purchasing and/or using Ethernet Services. Alternate term: Customer | 19, 6, 6.1, 10, 910.1, 13, 14, 2, 7, 15, 16, 23 |
| Subscriber-MA | Subscriber Maintenance Association | 25 |
| Subscriber-MEG | The MEG at Subscriber Level | 20 |
| S-VLAN | Service VLAN (also referred to as Provider VLAN) | 12 |
|
S-VLAN ID |
The 12 bit VID field in the S-Tag of an ENNI Frame. |
ENNI |
| TAF | Transport Adaptation Function | 12 |
| TALS | TDM Access Line Service | 3, 8, 11 |
| TCF | Transport Connection Function | 2 |
| TCI | Tag Control Information | 12 |
| TCP | Transmission Control Protocol | 2 |
| TDM | Time Division Multiplexing (examples of TDM services include Nx6, 6.14 kbit/s, DS1, DS3, E1, E3, OC3, STM1, OC12, STM3) | 2, 8, 11, 3 |
| TDM-bound | The direction of travel of CESoETH frames within the IWF receiving frames containing emulated circuit data from the MEN, and forwarding TDM data to the customer’s TDM-based equipment. | 8, 11 |
| TE | Transport Equipment | 4 |
| Tester | Special equipment used to generate and monitor traffic for verification purposes. | 9 |
| Test-MA | Test Maintenance Association | 25 |
| Test-MEG | The MEG used by Service provider to test the connectivity to UNI-C. | 20 |
| them | towards, the direction of the LAN | 25, 25 |
| T-Line | TDM Line Service | 3, 8, 11 |
| TLV | Type, Length, Value | 20,21, 24 |
| TLV | Type, Length and Value | 16 |
| TRAN | Transport Layer | 12, 17, 2, 4 |
| Transparency | A term used to describe that the content of a Service Frame is delivered unaltered across a MEN | 6, 6.1 |
| Transport | A specific TRANS layer technology | 2 |
| TRAN-trail | A TRAN-trail (see ITU-T Recommendation G.805) is a “transport entity” responsible for the transfer of information from the input of a trail termination source to the output of a trail termination sink. | 2 |
| TrCP | Traffic Conditioning Point | 17 |
| TSP | TDM Service Processing | 3, 8, 11 |
| TTF | Trail Termination Function | 2 |
| UNI | The UNI is the physical interface or port that is the demarcation between the customer and the service provider/Cable Operator/Carrier/MSO | 3, 6, 6.1, 7, 8, 9, 10, 10.1, 11, 14, 15, 16, 19, 13, 2, 4, 12, 17,20,21,22,23,24, 25 |
| UNI C | A compound functional element used to represent all of the functional elements required to connect a MEN subscriber a MEN implementing a UNI N. | 2 |
| UNI EVC ID | A UNI service attribute | 6, 6.1 |
| UNI ID | The Identifier for a UNI | 20 |
| UNI Identifier | A UNI service attribute | 6, 6.1 |
| UNI List | An EVC service attribute | 6, 6.1 |
| UNI Maximum Transmission Unit Size | The maximum sized Service Frame allowed at the UNI. | 10.1 |
| UNI MTU | The maximum sized Service Frame allowed at the UNI. | 6.1, 10.1 |
| UNI-C | Part of the UNI that is located at Customer Equipment | 20,21,24, 25 |
| Unicast Service Frame | A Service Frame that has a unicast destination MAC address | 9, 13, 7, 15, 19, 10, 10.1, 14 |
| Unicast Service Frame Delivery | An EVC service attribute | 6, 6.1 |
| UNI-MA | User-to-Network Interface Maintenance Association | 25 |
| UNI-MEG | UNI Maintenance Entity Group | 20 |
| UNI-N | A compound functional element used to represent all of the functional elements required to connect a MEN to a MEN subscriber implementing a UNI C. The functional elements within the Customer Edge that supports the MEN Subscriber’s technical capabilities and compliance to the UNI specification. A set of one or more functional elements that supports the MEN Service Provider’s technical capabilities and compliance to the UNI specification. | 2,20,21,25, 24 |
| Unscheduled Downtime | A time interval not agreed upon by both the Subscriber and Service Provider during which the Service Provider determines that the service is not usable. | 10.1 |
| Up | MEP A MEP residing in a Bridge that transmits CFM PDUs towards, and receives | 25 |
| Up-MEP | A MEP in an IEEE 802.1 Bridge that sends frames toward the Bridge Relay Entity; see [IEEE 802.1ag] | 20 |
| User Network Interface | The User Network Interface (UNI) is the physical interface or port that is the demarcation between the customer and the service provider/Cable Operator/Carrier/MSO. The physical demarcation point between the responsibility of the Service Provider and the responsibility of the Subscriber. | 6, 6.1, 2, 7, 15, 19, 10, 10.1, 14, 9,21, 23 |
| VC | Virtual Container | 3 |
| VID | VLAN Identifier | 25 |
| VLAN | Virtual Local Area Network | 4, 7, 12, 15, 6, 6.1, 8, 11,22,23, 25 |
| VLAN ID | VLAN Identifier | 12 |
| VPLS | Virtual Private LAN Service | 12, 17, 17 |
| VPWS | Virtual Private Wire Service | 17 |
| VT | Virtual Tributary | 3 |
| WAN | Wide Area Network | 4, 12 |
| WG | WG is the amount of traffic accepted as Green over the time interval T that should be delivered to the egress UNI | 19 |
| WTR | Wait to Restore | 2 |
| WY | WY is the amount of traffic accepted as Yellow over the time interval T that may be delivered to the egress UNI | 19 |
| xSTP | Spanning Tree Protocol (multiple variations) | 17 |