GPON Doctor 4k7

Ideal for GPON Installation,
Interoperation, Certification,
and Troubleshooting tool

Capture and Analyze
in ONE click

Independence for QoS Evaluation,
Real-time IP traffic extraction,
Service regeneration, Portable

GPON Doctor 4k7

The GPON Doctor 4k7 is a chipset-less portable passive GPON FTTH protocol analyser. It connects to a distribution fibre point of a GPON network and captures bit-level data in the upstream and downstream and interprets all control information at PLOAM and OMCI levels.

GPON Doctor 4k7 is the ultimate solution for troubleshooting, certification, and interoperability analysis in GPON deployment. It is specifically designed to cater to the needs of GPON deployment operators, installers, and hardware manufacturers. The solution comprises of GPON data acquisition hardware, a high-performance chassis/device, and software for analyzing the acquired data.

The capture hardware is self-implemented with state-of-the-art optical modules and large processing capacity, ensuring the highest level of performance and reliability. The device synchronizes seamlessly with the upload and download link at any point of the GPON fiber and automatically calibrates itself, enabling long-term captures. Furthermore, it expertly extracts and decrypts Ethernet traffic from the upper layer in real-time, allowing for the seamless regeneration of services.

Fig 1. GPON Doctor 4k7 in operation with a labtop.

This solution is intended for problem detection, certification, and interoperability analysis and represents the optimal solution for deployment operators, installers, and GPON hardware manufacturers.

Key Features

GPON Doctor uses captured data to deduce the network topology and applies a set of rules to certify whether the ITU-T G.984.x recommendation is met. Its automatic adaptive timing, automatic calibration, and intuitive interface make it easy to use from day one. It accurately detects problems in a GPON network, evaluates and details the equipment causing the problem, and identifies the cause of the failure.

Real-time extraction

The 10/100/1000BaseT interface enables the extraction and decryption of real-time Ethernet layer user traffic, which can be monitored and analyzed using external tools like external tools like WireShark. The hardware is equipped with an AES decryption engine.

Regeneration and QoS

The GPON Doctor 4k7 is capable of regenerating services in a PON network, including real-time extraction and reassembly of multicast video for QoS and QoE evaluation. This feature is essential for accurately evaluating services configured over a PON.

Fig 2. On-site FTTH troubleshooting related to GPON protocol.

Real-time GPON Capture

GPON Doctor 4k7 captures OMCI and GTC messages over the fibre in real-time, allowing for easy monitoring of negotiation processes and configurations. The tool provides real-time status updates on ONTs, GEM ports, and T-CONTs, ensuring efficient network management.

Analysis with Diagrams

It features a comprehensive OMCI entity/relationship diagram that showcases alarms and errors, ONT port and T-CONT bandwidth allocation diagrams, and time evolution diagrams. Additionally, it highlights a chipset-less hardware manufactured exclusively for this device enabling results independent of the proprietary implementation of any GPON equipment vendor.

Upstream + Downstream

When GPON Doctor 4k7 is that connected to a GPON fiber point captures bit level data in downstream and upstream, interpreting all control information at PLOAM and OMCI levels. It is capable of synchronizing at any point of the GPON fiber and automatically calibrates itself, allowing long-term captures. It also extracts and decrypts Ethernet traffic in real time.


Optimizing GPON

Deploying multi-vendor ONUs is a viable solution to reduce CAPEX. Any OLT can interact with any ONT, regardless of the manufacturer, thus facilitating interoperability between vendors. A PON network's structure involves splitting a fibre using optical power dividers or splitters. The degree of splitting determines the percentage of optical power that reaches an ONT. Controlling attenuation is crucial to prevent any of the network's active elements from operating under stressed conditions. GPON Doctor

Fig 3. GPON Doctor 4k7 in Operation.

Neutral analysis and Capture

GPD captures and analyzes traffic within an FTTH network in accordance with ITU-T standards. Its automatic calibration, built-in touch screen, and high-performance chassis allow for the complete capture and analysis of GPON network traffic with just one click.

GPD 4k7 has several captures modes, from a “Full capture” to get all control and management traffic for in-depth troubleshooting to “Real-Time” that allows captures over long time periods to identify deviations from expected behavior. The information captured can also be shared with other experts that can analyze it in their own computers using the GPD software.

Analysis and Assessment

The analysis software interprets captured information and presents it in a graphical and categorized format for in-depth analysis of GPON protocol compliance, interoperability evaluation, bandwidth allocation, and field troubleshooting.

GPD 4k7 allows for real-time extraction of clear-text user traffic in both upstream and downstream directions at the GbE layer.


To further analyze this traffic, you can use external or software-based upper-layer protocol analyzers. By combining GPONDoctor with a traffic generator and an external or internal analyzer that incorporates GPONDoctor 4k7, you can create a powerful setup to validate the correct transmission of 'IP services' over the network.

Additionally, this feature can be used to regenerate IP services within GPONDoctor. The IPTV channels and VoD streams reproduce the voice stream in real-time to analyze their QoS and QoE and confidently identify any degradation in services

GPON Doctor

Fig 4. Analysis GPON Doctor 4k7 (click to enlarge).

Laboratory & Field Operation

Being portable, battery-powered, and rugged it is an ideal companion for FTTH problem identification in the field, concerning GPON protocol or IP service provisioning. It also serves as a potent tool for interoperability checking and conformance validation.