Optical interface / PMD
The optical signaling specification at the media side of a connection.
Match the full optical interface at both endpoints. A shared aggregate rate or pluggable package does not establish a match.
WBN / Engineering glossary
Engineering glossary
Precise definitions for planning, documenting and troubleshooting network infrastructure.
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30 terms
Host electrical application
The electrical lane arrangement and signaling application between a host and its module.
Record lane count, lane rate and the selected application separately from the optical interface. The host must expose the required mode.
Breakout
A supported division of one interface into several independently usable connections.
A harness routes fibers or conductors; it does not create breakout capability. Record host lane grouping, module application and every destination.
Scale-up fabric
The interconnect within a tightly coupled accelerator domain.
For the NVIDIA systems described in our architecture guides, this is the NVLink domain. Keep it separate from the external network when counting connections.
Scale-out fabric
The network connecting separate accelerator systems or domains.
Identify the Ethernet or InfiniBand endpoints and topology independently of the internal accelerator interconnect and the storage or management networks.
Oversubscription
A relationship between the traffic capacity offered to a network tier and the capacity available through its uplinks.
State the direction, tier and rate assumptions. Switch ASIC aggregate bandwidth alone does not describe an installed fabric's uplink capacity.
Protocol support
Support for the particular network protocol used by the endpoint connection.
Ethernet and InfiniBand requirements must be checked against the exact adapter, firmware, module and operating mode; a nominal rate is insufficient.
Forward error correction / FEC
Coding that allows a receiver to detect and correct errors within the limits of the selected scheme.
Record the required FEC and where it operates. Host settings and coherent line FEC are distinct parts of the configuration.
Module coding
The identity and management information a module presents to its host.
Reading the intended identity establishes identification evidence. It does not establish thermal fit, optical interoperability or a completed qualification.
Qualification
A recorded test result for a defined combination of hardware, software, operating mode and test scope.
Preserve module and host revisions, settings, traffic conditions and error observations. Evidence for a different part or release cannot silently qualify the proposed connection.
OSFP IHS
An OSFP mechanical implementation with an integrated heatsink.
The finned module provides part of the thermal interface. Confirm the host's required module geometry, airflow and power envelope; OSFP alone is not a complete mechanical specification.
OSFP RHS
An OSFP implementation intended for a riding heatsink supplied by the host.
The host thermal interface contacts the module. Do not substitute an IHS or another flat-top implementation based only on speed or connector fit.
Single-mode fiber / SMF
The fiber medium specified for single-mode optical interfaces.
Retain the actual fiber specification and installed route. A module's wavelength, interface and connector requirements still need to match the other endpoint.
Multimode fiber / MMF
The fiber medium specified for multimode optical interfaces.
Record the actual fiber grade, such as OM3 or OM4, and the optical interface. Do not carry a reach value from one grade or application to another.
Polarity
The mapping that connects transmit positions to the intended receive positions across the complete fiber path.
Compose the strand map through patches, trunks, cassettes and adapters. A component's polarity label does not prove the final endpoint mapping.
Connector pinning
The presence or absence of alignment pins at a multifiber connector mating interface.
Record both sides of each mate along with key orientation and viewing direction. Do not infer the mating arrangement from the shell name alone.
Connector polish
The specified end-face geometry of a fiber connector, such as APC or UPC.
Match the actual mating interfaces. Connector shape, pinning and polish are separate fields in the assembly record.
Insertion loss
The reduction in optical power introduced by an element or path, expressed in dB.
Record the applicable wavelength and measurement context. Keep measured path loss, estimated contributions and engineering allowance distinct.
Jacket material
The material or construction designation of the cable's outer jacket, such as PVC or LSZH.
Material and installation rating are separate attributes. An LSZH description must not populate a missing fire-rating or listing field.
Cable safety rating
The documented rating or listing relevant to a cable's installation requirements.
Compare the required rating with evidence for the exact assembly. Keep an unsupported rating open; a material label is not a substitute.
Direct attach copper / DAC
A passive copper cable assembly connecting compatible electrical interfaces.
Compare both ends, the supported length and lane mode with the host documentation. A matching plug does not establish electrical support.
Active copper cable / ACC
A copper cable assembly incorporating active signal conditioning.
Preserve the manufacturer's construction description and endpoint requirements. Do not assume ACC and AEC are interchangeable names or implementations.
Active electrical cable / AEC
An active electrical cable assembly with powered signal-processing electronics.
The exact implementation, power requirements and host support belong in the connection record. Do not infer support from a passive cable of the same length.
Active optical cable / AOC
An integrated cable assembly with optical transmission between its powered endpoints.
Record both host interfaces and the physical route. Its integrated optical construction differs from a pair of separate modules connected by replaceable passive fiber.
Coherent operating mode
The complete line-side application, including framing, modulation, FEC and associated optical conditions.
Match the mode and peer implementation explicitly. A shared rate, media code or tunable frequency range does not establish interoperability.
Optical signal-to-noise ratio / OSNR
The ratio between optical signal power and optical noise power under a stated measurement convention.
Retain the noise reference bandwidth and mode requirement. Received power alone does not establish the quality of an amplified path.
Chromatic dispersion / CD
The wavelength-dependent propagation delay accumulated along an optical route.
Compare accumulated dispersion with the selected mode's documented compensation range and power conditions. A ps/nm limit is not a guaranteed distance.
EDFA gain
The optical amplification provided by an erbium-doped fiber amplifier under its specified operating conditions.
Check the operating wavelength band, input range, gain mode, output limit and noise behavior together. Gain alone cannot prove route feasibility.
Aggregate optical power
The total optical power contributed by the channels present at the measurement point.
Sum channel powers in linear units before converting to dBm. Keep signal loading, total-output limits and measurement assumptions explicit.
Channel width and tuning grid
Channel width describes the spectral allocation for a signal; a tuning grid describes selectable center-frequency steps.
A fine frequency step does not imply that a signal occupies that width. Check the complete mux, demux and ROADM filter path for the selected mode.
No matching terms
Try a shorter phrase or clear the current filters.
These definitions summarize the linked engineering references. Check the specific host, module and operating mode before applying them to a link.