HW assisted IEEE 1588 clock synchronization under Linux

OData support
Dr. Kovácsházy Tamás
Department of Measurement and Information Systems

This thesis presents a solution for reliable and cost-effective implementation of a high accuracy time synchronization system in Local Area Networks via the IEEE 1588 protocol.

Nowadays the necessity of sub-microsecond time synchronization is increasing in the fields of distributed systems and multimedia systems.

By the usage of the general purpose communication protocols such as Ethernet for synchronization, the cost and complexity can be lower compared to ordinary systems (e.g. via GPS and IRIG synced nodes).

There are several current applications of high accuracy in--band clock synchronization such as power substation automation, high frequency trader financial systems, telecommunications, etc.

This thesis shows a reliable solution for Linux based systems to attain this goal.

The Ethernet based multimedia systems provide a less complex and cost effective alternative to the multimedia specific connections based systems by eliminating the proprietary and single-function connections (VGA, DVI, HDMI) with the help of packet based clock synchronization.

The document systematizes the earlier works in this field, and presents an IEEE 1588--hardware time stamping based solution for the high accuracy i.e. sub-microsecond synchronization.

A high accuracy clock output (1PPS) is designed and presented in this work.

This output can be used for the distribution of the correct time to other devices, which can't use the PTP protocol stack, and it's also used for the validation of the measurements.

Every clock sync system requires a high precision time source for the most accurate synchronization process.

In the measurements, the demo system contains a high precision GPS based PTP master clock hardware.

The thesis also shows the design and implementation issues of a substituting equipment.

The performance of the network routing/switching equipment is critical for the decent accuracy.

The tests of the system are performed with PTP & non PTP compliant switching devices with variable loads to cover the largest real world application cases.


Please sign in to download the files of this thesis.