Time-Aware Applications, Computers, and Communication Systems (TAACCS)

Abstract

A new economy built on the massive growth of endpoints on the internet will require precise and verifiable timing in ways that current systems do not support. Applications, computers, and communications systems have been developed with modules and layers that optimize data processing but degrade accurate timing. State-of-the-art systems now use timing only as a performance metric. Correctness of timing as a metric cannot currently be designed into systems independent of hardware and/or software implementations. To enable the massive growth predicted, accurate timing needs cross-disciplinary research to be integrated into these existing systems. This paper reviews the state of the art in six crucial areas central to the use of timing signals in these systems. Each area is shown to have critical issues requiring accuracy or integrity levels of timing, that need research contributions from a range of disciplines to solve.

Time transfer over a White Rabbit network

“…After seminal work by Jefferts et al [3], using SONET or SDH frames, relatively few experiments were carried out over the following decade as Global Navigation Satellite System (GNSS) solutions fulfilled most needs. However weaknesses of GNSS solutions, such as their vulnerability to jamming or spoofing, but also the increasing need for accurate and secure time dissemination for critical applications, have led to renewed interest for this research [4]. There has been an increasing demand for access to precise time and frequency standards in areas such as telecommunication, navigation, internet, metrology for industry and for scientific applications.…”

A Survey of Clock Synchronization Over Packet-Switched Networks

“…As noted in the recent NIST report [3], time-aware systems, such as many Internetof-Things applications, require highly accurate time-based devices to be deployed in large-scale. Synchronized sensors are important in law enforcement, military and crisis applications.…”

“…The current version, NTP version 4, is formalized in IETF RFCs 5905-5908 and provides protocol and algorithm specification, public key authentication, and data exchange format. 3 NTP is implemented as an application using User Datagram Protocol (UDP) services, meaning it operates only on the end systems between the NTP server and NTP clients, as depicted in Fig. 6.…”

“…CPSs will be deployed in several functional domains, including in smart infrastructures (e.g., power grid, water), smart buildings, smart healthcare, and smart transportation to name a few domains. Time synchronization will play a critical role for the realization of CPSs as reported by a subgroup of the NIST CPS PWG in a recent technical report [3].…”

“…In [3], the authors specify that significant research is required in an integrated fashion for the realization of emerging new time-aware applications, computers, and communications systems (TAACCS), decomposed into the following principle areas of research: (1) time and frequency transfer, (2) clock and oscillator design, (3) use of synchronized timing in communications networks, and (4) hardware and software architecture, applications and systems design. In this paper, we focus on the time and frequency transfer area considering the time synchronization of devices connected by packet switched networks.…”