A electrical card protection scheme that pairs a working card with a protect card of the same type in an adjacent slot. If the working card fails, the traffic from the working card switches to the protect card. When the failure on the working card is resolved, traffic reverts back to the working card if this option is set. This protection scheme is specific to electrical cards.
An optical card protection scheme that pairs a single working card with a single dedicated protect card. A term specific to optical cards.
An electrical card protection scheme that allows a single protect card to provide protection for several working cards. If a working card fails, the traffic from the working card switches to the protect card.When the failure on the working card is resolved, traffic reverts to the working card.
Standard 10-Mbps local area network over unshielded twisted pair copper wire.
Standard 100-Mbps local Ethernet network.
Specification of 100BaseT that supports full duplex operation.
Point where network devices can access the network.
A card that is working or carrying traffic. A card provisioned as working can be an active card or, after a protection switch, a protect card can be an active card.
Bit combination used to describe the portion of an IP address that refers to the network or subnet and the portion that refers to the host. Sometimes referred to as mask.
See also subnet mask.
add/drop multiplexer. ADMs aggregate or groom SONET traffic at various speeds. An ADM has three or more nodes.
1. Generally, software that processes queries and returns replies on behalf of an application.
2. In a network management system, a process that resides in all managed devices and reports the values of specified variables to management stations.
Alarm Expansion Panel.
access identifier. An access code used in TL1 messaging that identifies and addresses specific objects within the ONS 15454. These objects include individual pieces of equipment, transport spans, access tributaries, and others.
See also TID.
alarm interface panel.
Automatic laser shutdown. A protocol that, in the event a remote link is broken, automatically reduces the optical output power of remote transmitters.
alternate mark inversions
automatic node setup.
alternate mark inversion. Line-code format used on T1 circuits that transmits ones by alternate positive and negative pulses. Zeros are represented by 01 during each bit cell and ones are represented by 11 or 00, alternately, during each bit cell. AMI requires that the sending device maintain ones density. Ones density is not maintained independently of the data stream. Sometimes called binary-coded alternate mark inversion.
Short name for the backplane electrical interface assembly equipped with AMP Champ connectors.
American National Standards Institute.
Acoustic-Optic Tunable Filter. Wavelength filter used to add/drop specific channels within the MSTP under software control.
automatic power control.
automatic protection switching. SONET switching mechanism that routes traffic from working lines to protect lines if a line card failure or fiber cut occurs.
alarm protection switching byte.
Address Resolution Protocol.
application-specific integrated circuit.
Asynchronous Transfer Mode
autonomous message tag. Sequential number generated by the system tat is used for TL1 message sequencing. See also CTAG.
Asynchronous Transfer Mode. The international standard for cell relay, in which multiple service types (such as voice, video, or data) are conveyed in fixed-length (53-byte) cells. Fixed-length cells allow cell processing to occur in hardware, thereby reducing transit delays. ATM is designed to take advantage of high-speed transmission media such as E3, SONET, and T3.
The decrease in signal strength in an optical fiber caused by absorption and scattering. Attenuation can be calculated to express the signal loss between two points, or the total signal loss of a telecommunications system or segment.
automatic laser shutdown
automatic protection switching
autonomous message tag
American Wire Gauge, or arrayed waveguide grating
binary 8-zero substitution. A line-code type, used on T1 circuits, that substitutes a special code whenever eight consecutive zeros are sent over the link. This code is then interpreted at the remote end of the connection. This technique guarantees ones density independent of the data stream. Sometimes called bipolar 8-zero substitution.
The part of the network that carries the heaviest traffic or joins LANs together.
bit error rate. Ratio of received bits that contain errors.
bidirectional line switched ring
binary-coded alternate mark inversion
binary 8-zero substitution
bit interleaved parity. In ATM, a method used to monitor errors on a link. A check bit or word is sent in the link overhead for the previous block or frame. Bit errors in the payload can then be detected and reported as maintenance information.
bit error rate
bit interleaved parity
Speed at which bits are transmitted, usually expressed in bits per second.
building integrated timing supply. A single building master timing supply that minimizes the number of synchronization links entering an office.
bidirectional line switched ring. A SONET ring architecture that provides working and protection fibers between nodes. If the working fiber between nodes is cut, traffic is automatically routed onto the protection fiber.
Compare with path protection.
Dense wavelength division multiplexing (DWDM) wavelengths are broken into two distinct bands: red and blue. DWDM cards for the ONS 15454 operate on wavelengths between 1530.33 nm and 1542.94 nm in the blue band. The blue band is the lower frequency band.
Device that connects and passes packets between two network segments that use the same communications protocol. In general, a bridge will filter, forward, or flood an incoming frame based on the MAC address of that frame.
See also MAC address.
Data packet that will be sent to all nodes on a network. Broadcasts are identified by a broadcast address.
Compare with multicast
See also broadcast address.
Special address reserved for sending a message to all stations. Generally, a broadcast address is a MAC destination address of all ones.
See also MAC address.
Undesirable network event in which many broadcasts are sent simultaneously across all network segments. A broadcast storm uses substantial network bandwidth and, typically, causes network timeouts.
building integrated timing supply
Common physical signal path composed of wires or other media across which signals can be sent from one part of a computer to another.
The C2 byte is the signal label byte in the synchronous transport signal (STS) path overhead. This byte tells the equipment what the SONET payload envelope contains and how it is constructed. See also
Category 5 (cabling).
conventional band. In optical networks, a range of wavelengths between 1535 nm and 1565 nm.
Comité Consultatif International Télégraphique et Téléphoniques. Formerly ITU.
Controlled Environment Vaults.
Cisco Transport Controller
Cisco Transport Manager
Common Language Equipment Identification code.
Connectionless Network Protocol.
Common Management Information Protocol.
Central Office Environment.
In Ethernet, the result of two nodes transmitting simultaneously. The frames from each device impact and are damaged when they meet on the physical media.
A mechanism for allocating contiguous bandwidth for payload transport. Through the use of concatenation pointers, multiple OC-1s can be linked together to provide contiguous bandwidth through the network, from end to end.
Coordinated Universal Time
Common Object Request Broker Architecture.
Customer Premise Equipment.
A set of physical or logical contacts that operate together to extend the speech and signal channels in a switching network.
correlation tag. A unique identifier given to each input command by the TL1 operator. When the ONS 15454 system responds to a specific command, it includes the command's CTAG in the reply. This eliminates discrepancies about which response corresponds to which command.
See also ATAG.
Cisco Transport Controller. A Java-based graphical user interface (GUI) that allows operation, administration, maintenance, and provisioning (OAM&P) of the ONS 15454 using an Internet browser.
Cisco Transport Manager. A Java-based network management tool used to support large Cisco 15000-class networks.
data communications channel
data communications network
data communications channel. Used to transport information about OAM&P over a SONET interface. DCC can be located in SDCC or LDCC.
See also LDCC
data communications network. An out-of-band network that provides connectivity between network elements and their respective operations support systems (OSS).
Distributed Communications System.
dispersion compensation unit.
If the ONS 15454 must communicate with a device on a network to which the ONS 15454 is not connected, packets are sent to this router to be distributed.
To separate multiple multiplexed input streams from a common physical signal back into multiple output streams.
Compare with multiplex.
A device used to demultiplex signals.
An abbreviation used for demultiplex or demultiplexer.
dense wavelength division multiplexing
The endpoint where traffic exits an ONS 15454 network. Endpoints can be paths (STS or STS/VT for optical card endpoints), ports (for electrical circuits, such as DS1, VT, DS3, STS), or cards (for circuits on DS1 and Ethernet cards).
See also STS
Dynamic Host Configuration Protocol.
Digital Signal Cross-Connect Frame
Domain Name Service.
dynamic random-access memory.
digital signal level 1. A framing specification used in transmitting digital signals at 1.544-Mbps on a T1 facility (in the United States) or at 2.108-Mbps on an E1 facility (in Europe).
digital signal level 3. Framing specification used for transmitting digital signals at 44.736 Mbps on a T3 facility.
(Digital Signal Cross-Connect Frame). A manual bay or panel where different electrical signals are wired. A DSX permits cross-connections by patchcords and plugs.
dense wavelength division multiplexing. A technology that increases the information carrying capacity of existing fiber optic infrastructure by transmitting and receiving data on different light wavelengths. Many of these wavelengths can be combined on a single strand of fiber.
An ONS 15454 running Software Release 4.5, or later.
Compare with non-DWDM node.
erbium doped fiber amplifier. A type of fiber optical amplifier that transmits a light signal through a section of erbium-doped fiber and amplifies the signal with a laser pump diode. EDFA is used in transmitter booster amplifiers, in-line repeating amplifiers, and receiver preamplifiers.
Electrical Facility Connection Assembly.
Electrical Fast Transient/Burst.
electrical interface assembly. Provides backplane connection points for the DS-1, DS-3, and EC-1 cards.
Electronic Industries Association/Telecommunications Industry Association Recommended Standard No. 232.
electrical interface assembly
Extended Long Reach.
electromagnetic interference. Interference by electromagnetic signals that can cause reduced data integrity and increased error rates on transmission channels.
Element Manager Layer.
Element Management System.
end network element.
The part of messaging that varies in composition from one transmittal step to another. It identifies the message originator and potential recipients, documents its past, directs its subsequent movement by the Message Transfer System (MTS), and characterizes its content.
express orderwire. A permanently connected voice circuit between selected stations for technical control purposes.
erbium doped fiber amplifier
Enhanced Remote Defect Indicator.
End System Hello.
Extended Super Frame.
A type of Ethernet LAN device that increases aggregate LAN bandwidth by allowing simultaneous switching of packets between switch ports. Ethernet switches subdivide previously shared LAN segments into multiple networks with fewer stations per network.
European Telecommunications Standards Institute.
extended subnetwork connection protection). Extends the protection scheme of a subnetwork connection protection ring (SNCP) beyond the basic ring configuration to the meshed architecture of several interconnecting rings.
See also SNCP.
external timing reference
A timing reference obtained from a source external to the communications system, such as one of the navigation systems. Many external timing references are referenced to Coordinated Universal Time (UTC).
A falling threshold is the counterpart to a rising threshold. When the number of occurrences drops below a falling threshold, this triggers an event to reset the rising threshold.
See also rising threshold.
Fiber Distributed Data Interface. A LAN standard, defined by ANSI X3T9.5, specifying a 100-Mbps token-passing network using fiber optic cable, with transmission distances of up to 2 km. FDDI uses a dual-ring architecture to provide redundancy.
Frame Bit Errors.
forward error correction.
Frame Ground #1 (pins are labeled "FG1," "FG2," etc.)
Fiber Distributed Data Interface
Front Mount Electrical Connection.
Logical grouping of information sent as a data link layer unit over a transmission medium. Often refers to the header and trailer, used for synchronization and error control that surrounds the user data contained in the unit.
Field Service Bulletin.
An electronic repeater device that intercepts and steers electrical signals from one network to another.
Gigabit Interface Converter. A hot-swappable input/output device that plugs into a Gigabit Ethernet port to link the port with the fiber-optic network.
gigabits per second.
gigabytes per second.
generic communications channel.
Gigabit Interface Converter
gateway network element.
Telcordia General Requirements #253 Council of Registrars.
Telcordia General Requirement 1089,
Electromagnetic Compatibility and Electrical Safety - Generic Criteria for Network Telecommunications Equipment.
graphical user interface.
The physical removal and insertion of a TCC2/TCC2P card, also known as reseating a card or performing a card pull.
high-level data link control. Bit-oriented, synchronous, data-link layer protocol developed by the International Standards Organization (ISO). HDLC specifies a data encapsulation method on synchronous serial links using frame characters and checksums.
high-level data link control
A hop is a way to quantify the "length" of a network route to decide which redundant route is selected. Typically, each path segment through a routing network device is considered one hop. For example, if an ENE is connected to a GNE that is connected to a router, the ENE has two hops to the router—one from itself to the GNE and a second from the GNE to the router. To ensure that a certain route is used only when all other routes are exhausted, assign it an unusually high hop count.
The part of an IP address used to address an individual host within the network or subnetwork.
The process of replacing a failed component while the rest of the system continues to function normally.
1. InterExchange Carrier.
2. International Electrotechnical Commission.
Institute of Electrical and Electronics Engineers.
Internet Engineering Task Force.
Internet protocol. Network layer protocol in the TCP/IP stack offering a connectionless internetwork service. IP provides features for addressing, type-of-service specification, fragmentation and reassembly, and security.
intermediate-path performance monitoring.
A 32-bit address assigned to a host using TCP/IP. An IP address belongs to one of five classes (A, B, C, D, or E) and is written as 4 octets separated by periods (dotted decimal format). Each address consists of a network number, an optional subnetwork number, and a host number.
International Telecommunication Union-Telecommunication Standards Sector.
Java Runtime Environment.
Automatic protection-switching byte located in the SONET line overhead and monitored by equipment for an indication to switch to protection.
local area network. High-speed, low-error, data network covering a relatively small geographic area. LANs connect workstations, peripherals, terminals, and other devices in a single building or other geographically limited area. Ethernet, FDDI, and Token Ring are widely used LAN technologies.
line build out. The distance between an external timing device connected to the BITS Out pins and the ONS 15454.
(Liquid Crystal Display). An alphanumeric display using liquid crystal sealed between two pieces of glass. LCDs conserve electricity.
Line data communications channel.
Line Alarm Indication Signal
line build out
Refers to the segment between two SONET devices in the circuit. The line layer deals with SONET payload transport, and its functions include multiplexing and synchronization. Sometimes called a maintenance span.
line terminating equipment
line timing mode
A node that derives its clock from the SONET lines.
The difference between the output power and receiver power of an optical signal expressed in decibels (dB). Link refers to an optical connection and all of its component parts (optical transmitters, repeaters, receivers, and cables).
The network communications channel has link integrity if it is intact.
Liquid Crystal Display
local area network
A method of switching traffic from one card to another, or one span to another (BLSRs), that prevents traffic from reverting to the card or span where the lockout is applied. The lockout overrides other manual switching connections (Force, Manual, and Exercise).
Test that sends signals, and then directs them back toward their source from some point along the communications path. Loopback tests are often used to test network interface usability.
local orderwire. A communications circuit between a technical control center and selected terminal or repeater locations.
line terminating equipment. Refers to line cards that terminate the line signal in the ONS 15454.
Low-Voltage Differential Signal.
Media Access Control.
Standardized data link layer address that is required for every port or device that connects to a LAN. Other devices in the network use these addresses to locate specific ports in the network and to create and update routing tables and data structures. MAC addresses are six bytes long and are controlled by the IEEE. Also known as the hardware address, MAC-layer address, and physical address.
Intermediate System Hello.
A security level that limits user access to maintenance options only.
Compare with Superuser, Provisioning user,
and Retrieve user.
A network node that contains a Subnetwork Management Protocol (SNMP) agent and resides on a managed network. Managed devices include routers, access servers, switches, bridges, hubs, computer hosts, and printers.
In network management, a network device that can be managed by a network management protocol. Sometimes called an MIB object.
Management Information Base
A logical association between one set of values, such as addresses on one network, with quantities or values of another set, such as devices on another network.
megabits per second.
megabytes per second.
Cisco MetroPlanner is a network design tool that provides a means to construct and test wavelength division multiplexing (WDM) optical networks in a modeled graphical environment.
Management Information Base. Database of network management information that is used and maintained by a network management protocol such as SNMP or Common Management Information Protocol (CMIP). The value of a MIB object can be changed or retrieved using SNMP or CMIP commands, usually through a GUI network management system. MIB objects are organized in a tree structure that includes public (standard) and private (proprietary) branches.
Multipurpose Internet Mail Extensions.
Multifiber Push-On (connector).
multiplex section far-end receive failure.
Multiplex Section Protection.
multiplex section-shared protection ring. SDH ring architecture that provides working and protection fibers between nodes. If the working fiber between nodes is cut, traffic is automatically rerouted onto the protection fiber.
Message Transfer System
Single packets copied by the network and sent to a specific subset of network addresses.
Compare with unicast
Generates section and line overhead, and converts electrical/optical signals when the electrical/optical card is transmitting.
multiplex section-shared protection ring
To combine multiple signals so that they can be transmitted simultaneously across a single physical channel. Compare
A device used to multiplex signals.
An abbreviation used for multiplex or multiplexer.
network element. In an Operations Support System (OSS), a single piece of telecommunications equipment used to perform a function or service integral to the underlying network.
Network Equipment Building Systems.
Network Element Layer.
network management system
Part of an IP address that specifies the network where the host belongs.
network interface card
Network Management Layer.
network management system. System that executes applications that monitor and control managed devices. NMSs provide the bulk of the processing and memory resources required for network management.
In this manual, the term "node" usually refers to an ONS 15454. A node is the endpoint of a network connection or a junction common to two or more lines in a network. Nodes can be processors, controllers, or workstations. Nodes, which vary in routing and other functional capabilities, can be interconnected by links, and serve as control points in the network. Node is sometimes used generically to refer to any entity that can access a network.
An ONS 15454 running Software Release 4.1 or earlier.
Compare with DWDM node.
Network Service Access Point.
Node Service Protocol.
Node Topology Discovery.
optical add/drop multiplexer
operation, administration, maintenance, and provisioning. Provides the facilities and personnel required to manage a network.
optical channel network connection.
Out of Service Assigned.
operation, administration, maintenance, and provisioning
A device that amplifies an optical signal without converting the signal from optical to electrical and back again to optical energy.
An opto-electric circuit that detects incoming lightwave signals and converts them to the appropriate signal for processing by the receiving device.
Equipment that establishes voice contact between a central office and carrier repeater locations.
See also EOW
Optical Service Channel Module.
Open Systems Interconnection.
optical signal-to-noise ratio
Open Shortest Path First.
Operations Support System.
optical transport network
output contacts (controls)
Triggers that drive visual or audible devices such as bells and lights. Output contacts can control other devices such as generators, heaters, and fans.
Components that do not require external power to manipulate or react to electronic output. Passive devices include capacitors, resisters, and coils.
The segment between the originating equipment and the terminating equipment. This path segment might encompass several consecutive line segments or segments between two SONET devices.
Path-Protected Mesh Network
Path-switched SONET rings that employ redundant, fiber- optic transmission facilities in a pair configuration. One fiber transmits in one direction and the backup fiber transmits in the other. If the primary ring fails, the backup takes over.
Compare with BLSR.
Portion of a cell, frame, or packet that contains upper-layer information (data).
pulse code modulation.
Personal Computer Memory Card International Association.
Product Change Notice.
STS Payload Defect Indication-Path.
packet Internet grouper. Internet Control Message Protocol (ICMP) echo message and its reply. Often used in IP networks to test the reachability of a network device.
In SONET, the mechanism used to compensate for frequency and phase variations. Pointer justification counts indicate timing errors on SONET networks.
point of presence.
pluggable port module.
Path-Protected Mesh Network. Extends the protection scheme of a path protection beyond the basic ring configuration to the meshed architecture of several interconnecting rings.
Routing feature that divides data packets into two queues: one low-priority and one high-priority.
A card in a protection pair or scheme that is provisioned as a protect card to the working card. If the working card fails, the protect card becomes active.
See also working card.
A security level that allows the user to access only provisioning and maintenance options in CTC.
See also Superuser, Maintenance user,
and Retrieve user.
Protection Switching Count.
Protection Switching Duration.
In routing, a backlog of packets waiting to be forwarded over a router interface.
Remote Defect Indication-Line.
DWDM wavelengths are broken into two distinct bands: red and blue. The red band is the higher frequency band. The red band DWDM cards for the ONS 15454 operate on wavelengths between 1547.72 nm and 1560.61 nm.
A security level that allows the user to retrieve and view CTC information but not set or modify parameters.
Compare with Superuser, Maintenance user,
and Provisioning user.
A process that sends electrical interfaces (traffic) back to the original working card after the card comes back online.
Connection of two or more nodes in a logically circular topology. Information is passed sequentially between active nodes.
See also switching, ring.
The number of occurrences (collisions) that must be exceeded to trigger an event.
Registered Jack #45 (8-pin).
Return Materials Authorization.
(remote monitoring). Allows network operators to monitor the health of the network with an NMS. RMON watches several variables, such as Ethernet collisions, and triggers an event when a variable crosses a threshold in the specified time interval.
Fiber connector, push-pull type.
Serial Communication Interface.
System Communications Link.
Small Computer System Interface.
Section data communications channel.
Synchronous Digital Hierarchy. European standard that defines a set of rate and format standards that are transmitted using optical signals over fiber. SDH is similar to SONET, with a basic SDH rate of 155.52 Mbps.
Compare with SONET.
Severely Errored Frame.
Safety Extra-Low Voltage.
Severely Errored Seconds.
small form factor plugle
Simple Network Management Protocol
Simple Network Time Protocol
Service Management Layer.
Subnetwork Connection Protection. Path-switched SDH rings that employ redundant, fiber-optic transmission facilities in a pair configuration. One fiber transmits in one direction and the backup fiber transmits in the other. If the primary ring fails, the backup takes over.
Simple Network Management Protocol. Network management protocol used almost exclusively in TCP/IP networks. SNMP monitors and controls network devices and manages configurations, statistics collection, performance, and security.
Simple Network Time Protocol. Using an SNTP server ensures that all ONS 15454 network nodes use the same date and time reference. The server synchronizes alarm timing during power outages or software upgrades.
A soft reset reloads the operating system, application software, etc., and reboots the TCC2/TCC2P card. It does not initialize the ONS 15454 application-specific integrated circuit (ASIC) hardware.
Synchronous Optical Network. High-speed synchronous network specification developed by Telcordia Technologies, Inc. and designed to run on optical fiber. STS-1 is the basic building block of SONET. Approved as an international standard in 1988.
The endpoint where traffic enters an ONS 15454 network. Endpoints can be a path (STS or STS/VT for optical card endpoints), port (for electrical circuits, such as DS1, VT, DS3, or STS), or card (for circuits on DS1 and Ethernet cards).
See also STS
An optical path between two nodes.
See also switching, span.
A loop-free subset of a network topology. See also
Spanning Tree Protocol
synchronous payload envelope. A SONET term describing the envelope that carries the user data or payload.
synchronization status messaging. A SONET protocol that communicates information about the quality of the timing source using the S1 byte of the line overhead.
spanning-tree algorithm. An algorithm used by the Spanning Tree Protocol (STP) to create a spanning tree.
See also spanning tree
A card that is not active or carrying traffic. A standby card can be a protect card or, after a protection switch, a working card can be a standby card.
A route that is manually entered into a routing table. Static routes take precedence over routes chosen by all dynamic routing protocols.
1. shielded twisted-pair.
2. Spanning Tree Protocol. Bridge protocol that uses the spanning-tree algorithm to enable a learning bridge to dynamically work around loops in a network topology by creating a spanning tree.
See also spanning tree
Synchronous Transport Signal. Used generically when speaking of SONET signals.
Synchronous Transport Signal level 1. Basic building block signal of SONET, operating at 51.84 Mbps for transmission over OC-1 fiber. Faster SONET rates are defined as STS-
n is a multiple of 51.84 Mbps.
See also SONET.
A 32-bit address mask used in IP to indicate the bits of an IP address that are used for the subnet address. Sometimes referred to simply as mask.
See also IP address.
In IP networks, a network confined to a particular subnet address. Subnetworks are networks segmented by a network administrator in order to provide a multilevel, hierarchical routing structure while shielding the subnetwork from the addressing complexity of attached networks. Sometimes called a subnet.
Subnetwork Connection Protection
SONET rings that incorporate nodes that are also part of an adjacent SONET ring.
A security level that can perform all of the functions of the other security levels as well as set names, passwords, and security levels for other users. A Superuser is usually the network element administrator.
Compare with Retrieve user, Maintenance user,
and Provisioning user.
Span switching occurs when a working span fails. Traffic switches to the protect fibers between the nodes and then returns to the working fibers. Multiple span switches can occur at the same time.
Ring switching occurs when a span switch cannot recover traffic, such as when both the working and protect fibers fail on the same span. In a ring switch, traffic is routed to the protect fibers throughout the full ring.
SONET WAN switch.
SONET Cross Connect ASIC.
synchronization status messaging
Synchronous Digital Hierarchy
Synchronous Optical Network
synchronous payload envelope
Synchronous Transport Signal
T1 transmits DS-1-formatted data at 1.544 Mbps through the telephone-switching network using AMI or B8ZS coding.
See also AMI, B8ZS,
Cisco Technical Assistance Center.
Telemetry Byte Oriented Serial protocol.
threshold crossing alert.
Timing Communications and Control + Card.
Transmission Control Protocol/Internet Protocol.
time-division multiplexing. Allocates bandwidth on a single wire for information from multiple channels based on preassigned time slots. Bandwidth is allocated to each channel regardless of whether the station has data to transmit.
Telcordia Technologies, Inc., formerly named Bellcore. Eighty percent of the U.S. telecommunications network depends on software invented, developed, implemented, or maintained by Telcordia.
target identifier. Identifies the particular network element (in this case, the ONS 15454) where each TL1 command is directed. The TID is a unique name given to each system at installation.
See also AID.
Transaction Language 1.
transparent LAN services. Provides private network services across a SONET backbone.
Telecommunication Management Network.
Optional device in a DWDM system that provides the conversion of one optical wavelength to a precision narrow band wavelength.
See also DWDM.
Message sent by an SNMP agent to an NMS (CTM), console, or terminal to indicate the occurrence of a significant event, such as an exceeded threshold. See also
The lower-rate signal directed into a multiplexer for combination (multiplexing) with other low rate signals to form an aggregate higher rate level.
Network traffic travels across this physical and logical connection between two switches. A backbone is composed of a number of trunks.
See also backbone.
Secure communication path between two peers, such as two nodes.
Architecture that is designed to provide the services necessary to implement any standard point-to-point encapsulation scheme.
Universal Backplane Interface Connector-Horizontal. The UBIC-H EIAs provide up to 112 transmit and receive connections through 16 SCSI connectors per side (A and B). The UBIC-H EIAs are designed to support DS-1, DS-3, and EC-1 signals.
Universal Backplane Interface Connector-Vertical. The UBIC-V EIAs provide up to 112 transmit and receive connections through 16 SCSI connectors per side (A and B). The UBIC-V EIAs are designed to support DS-1, DS-3, and EC-1 signals.
user data channel.
User Datagram Protocol/Internet Protocol.
The communication of a single source to a single destination.
Compare with broadcast
Set of frequencies used to send data from a subscriber to the head end.
Coordinated Universal Time. Time zone at zero degrees longitude. Formerly called Greenwich Mean Time (GMT) and Zulu time.
volts direct current.
A fiber that carries signals at different rates and uses the same fiber-optic cable.
Entity in a source-route bridging (SRB) network that logically connects two or more physical rings together either locally or remotely. The concept of virtual rings can be expanded across router boundaries.
Routes external alarms to one or more alarm collection centers across the SONET transport network.
virtual LAN. Group of devices located on a number of different LAN segments that are configured (using management software) to communicate as if they were attached to the same wire. Because VLANs are based on logical instead of physical connections, they are extremely flexible.
variable optical attenuator.
Virtual Private Network. Enables IP traffic to travel securely over a public TCP/IP network by encrypting all traffic from one network to another. A VPN uses "tunneling" to encrypt all information at the IP level.
See also tunneling.
Virtual Tributary. A structure designed for the transport and switching of sub-DS3 payloads.
See also tributary.
A Virtual Tributary that equals 1.544 Mbps.
The VT layer, or electrical layer, occurs when the SONET signal is broken down into an electrical signal.
Allows electrical circuits to pass through ONS 15454 nodes without using ONS 15454 cross-connect card capacity.
wide area network.
A card that is provisioned as an active, primary card. Traffic cards in a protection pair are provisioned as working or protect.
See also protect card.
Wavelength Path Provisioning.
Protocol providing devices with direct connections to a packet-switched network.
Two cards connected together with a Y cable to form a protection group.