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Dolphin PCIe Copper / optical

Copper & Optical PCIe Links

Place PCIe devices where the system needs them—across a chassis, rack or equipment room—while retaining a native high-bandwidth data path.

PCIe generations

Gen3 · Gen4 · Gen5

Media

Copper · active optical

Interfaces

SFF-8614 · SFF-8644 · CDFP · MPO

Optical reach

Up to 200 m on selected optical links

SFF-8614 SFF-8644 CopprLink FireFly MPO fibre Clock isolation

Selection guidance: Dolphin cable products use model-specific copper or optical interfaces. Supported distance, lane grouping, clocking and active optical cable compatibility must match both link endpoints. Confirm adapter availability and the exact MPO cable construction for Gen5 FireFly optical configurations.

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System Capabilities

Copper and optical PCIe links provide physical-placement options while retaining a native PCIe connection between compatible system elements.

Flexible equipment placement

Position hosts, switches and expansion systems around rack layout, cooling, EMI and service-access constraints.

Distance matched to the installation

Use short-reach copper or longer-reach optical media according to the required route and supported product family.

Electrical separation options

Use optical links where galvanic separation of the data path, ground-potential differences or electrical-interference concerns make copper less suitable. Optical media does not by itself constitute certified protective or medical isolation.

Preserved PCIe transaction model

Maintain compatible endpoint drivers and PCIe semantics instead of introducing an application-level network protocol.

Technical Features

Key platform elements and integration considerations are outlined below.

Gen5 SFF-8614 links

Four x4 SFF-8614 ports can be aggregated as x8 or x16 on supported Gen5 adapters and switches. Current passive copper assemblies are offered up to 3 metres; cable-management and sideband compatibility must match the complete adapter-and-cable combination.

Gen5 CopprLink

CDFP-based CopprLink adapters provide one dense x16 PCIe 5.0 interface for transparent expansion or NTB networking. Current supported copper links extend to 3 metres and selected fibre implementations to 50 metres; both ends must use compatible hardware and firmware.

Gen5 FireFly optical

FireFly optical adapters use MPO-connected optical engines for electrically separated, longer-reach links. Current Gen5 FireFly products support up to 100 metres, while selected Gen4 FireFly families support up to 200 metres.

Gen4 SFF-8644 links

SFF-8644 supports PCIe 4.0 copper connections up to 5 metres and active optical connections up to 100 metres across compatible host adapters, PXIe or CompactPCI Serial modules and external switches. The path negotiates to the highest common generation and width.

Gen3 installed-base support

SFF-8644, iPass and related cable families support deployed Gen3 systems. Connector compatibility alone does not guarantee matching lane reversal, clocking or sideband behaviour.

Link engineering

Passive copper is suited to short rack-level runs, while active optical provides reach and electrical separation. Bend radius, retention, airflow and service routing affect practical reliability.

Specifications

Technical parameters and system-integration requirements are listed below.

Copper & Optical PCIe Links architecture and integration parameters
Parameter	Unit	Value / Description
LINK ARCHITECTURE
PCIe generation	—	Gen3, Gen4 or Gen5 across both adapters, switches and intermediate modules.
Lane organisation	lanes	x4 cable links; supported products aggregate links as x8 or x16.
Connector families	—	SFF-8614, SFF-8644, CDFP CopprLink, FireFly optical engines and legacy iPass families.
Operating mode	—	Transparent host/target expansion or NTB host-to-host networking, depending on adapter pair.
DOLPHIN CABLE FAMILIES
PCIe 3.0 SFF-8644	PCIe3L / MSFC	x4 CMI copper cables from 0.5–5 m; compatible AOC assemblies to 100 m for supported Gen3 SFF-8644 products.
PCIe 4.0 SFF-8644	PCIe4L / MSF4C	x4 CMI copper cables from 0.5–5 m and optical assemblies to 100 m for supported Gen4 SFF-8644 products.
PCIe 5.0 SFF-8614	PCIe5L	x4 CMI copper cables in 1 m, 2 m and 3 m lengths for MXH530/MXH532 and compatible Gen5 products.
PCIe 5.0 CopprLink CDFP	PCPR5C / PCPR5FC	x16 CDFP copper cables from 1–3 m and published optical assemblies for MXH570/MXH572.
FireFly MPO patch	MTFC4FF / MTFC8FF	x4 and x8 optical patch cables; published lengths reach 200 m on compatible FireFly adapter configurations.
Legacy iPass	IXC	x8 Gen3 copper family for IXH/PXH/MXH products listed by Dolphin. OEM status: end-of-life; retain only for installed-base service.
MEDIA & DISTANCE
Passive copper	—	Typical current limits are up to 3 m for Gen5 SFF-8614 or CDFP copper and up to 5 m for Gen4 SFF-8644 copper; exact support is model-specific.
Active optical	—	Model-specific active optical or optical-engine links extend to 50 m, 100 m or 200 m depending on generation and interface family.
Clocking	—	Host clock isolation, SSC and cable-link clock handling depend on the selected adapter family.
Sideband support	—	Cable management, reset, presence and power signalling must be compatible across the complete link.
INTEGRATION
Compatibility	—	Adapters, cable assemblies and target hardware must use matching generation, port width and pinout.
Installation	—	Observe bend radius, connector retention, airflow, optical cleanliness and service access.
Performance	—	Usable bandwidth depends on negotiated generation, lane width, protocol overhead and switch hops.
Diagnostics	—	Supported board-management tools expose link state and PCIe error information.

Applications

The architecture is most useful where native PCIe access, sustained data movement or tightly coupled multi-node communication materially affects the system.

Rack-level expansion

Connect nearby servers, switches and expansion chassis with short copper links while preserving native PCIe enumeration and driver access.

Remote instrumentation

Place acquisition, FPGA or protocol hardware closer to sensors and test racks while keeping the controlling computer in a separate service location.

Multi-rack laboratories

Use active optical links between test racks where copper distance, cable bulk or ground-potential differences make direct copper routing impractical.

Aerospace and defence integration

Connect distributed processing and I/O subsystems using optical links where electrical separation is useful; environmental qualification remains a system-level responsibility.

Medical imaging systems

Separate image acquisition or acceleration hardware from operator-side compute without claiming the PCIe link itself provides medical electrical isolation.

Accelerator and storage fabrics

Route GPU, FPGA and NVMe traffic through engineered copper or optical paths in scalable compute and recording systems.

Dolphin engineering reference

Technical reading for this system decision

Open the original Dolphin or Dolphin-partner document directly. Confirm current model and software compatibility separately for the selected configuration.

PCIe over optics in embedded applicationsOptical reach, transparent expansion and NTB topology guidance.Open PDF ↗

System design guidance

Recommended System Architectures

See how this product family fits into transparent expansion, multi-host fabrics and managed-resource systems.

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