Don’t Ethernet networks require synchronisation?
Operating PDH and SDH networks would be impossible without accurate synchronisation of the network devices. Synchronisation is required so that a continuous data stream is read in and out at the same speed at the inlet and outlet to the network.
In packet networks (Ethernet, IP, MPLS…), synchronisation isn’t even necessary just to transmit the data because packet transmission compensates for the differences in speed at the inlet and outlet to the network. However, an increasing number of applications require the correct time, or synchronisation of frequency and phase. As a result, synchronisation transmission via packet networks is becoming increasingly important to many network operators.
To make their applications more powerful, many industries use highly accurate transmission of synchronisation over transport networks.
Precision time protocol (PTP) is the preferred method
PTP, also called 1588v2, is the protocol that transmits highly accurate information about frequency, phase, and ToD (Time of Day) via packet networks. Due to its greater accuracy (compared with the NTP or Network Timing Protocol), PTP is used for synchronising wide-area networks. By just using PTP-aware devices in the network, accuracies of 100 ns phase deviation are possible.
GNSS (Global Navigation Satellite System) clocks
Nowadays, satellite navigations systems are mostly used as the reference time when synchronising telecommunications networks:
  • GPS (US)
  • GLONASS (Russian Federation)
  • Galileo (European Union)
  • BeiDou (People’s Republic of China)
However, when using GNSS systems, it’s important to remember that the satellite signal’s availability may be limited by atmospheric disturbances, technical problems and jamming or spoofing attacks. Therefore, high-precision frequency standards (cesium) are often used in combination with GNSS receivers to compensate for periods when GNSS systems aren’t available.
Oscilloquartz has longstanding experience with clocks and synchronisation
Oscilloquartz is a traditional Swiss manufacturer of clocks and synchronisation equipment. The company, which now belongs to ADVA Optical Networking, supplies equipment for distributing synchronisation in all types of telecommunications networks. The broad product range covers high-precision caesium frequency standards for the core network to SFP grandmaster clocks.

Some of the products in Oscilloquartz’s range:

ADVA: OSA 5430

Modular synchronisation solution for network timing with 10G interfaces. IEEE 1588 grandmaster clock with support of PTP, NTP and SyncE via several 10Gbit/s Ethernet interfaces, as well as 1Gbit/s interfaces with hardware time stamps for precise timing requirements.
OSA 5430
Exceptional characteristics are as follows:
  • Integrated Snycjack assurance functionality
  • Modular, scalable design
  • Redundant architecture
  • Hot swappable modules

ADVA: OSA542x

A family of IEEE l588v2 PTP synchronisation devices with testing functions and GNSS assurance monitoring with NTP server and GNSS receiver and multiple sync fanout options for use at the edge of the mobile telephone network and other packet-driven transmission networks. Also ideal for legacy networks and migration to packet networks.

ADVA: OSA 5422

OSA 5422
Characteristics:
  • 8 x 1G/10G optical fibre ports
  • 2 x electric Ethernet ports 100/1G
  • 2 x additional slots/h5>
  • 2 x BITS in/out
  • 5G-ready: optional multiband GNNS-receiver in PRTC-B quality
  • Boundary clock accuracy class C and D

ADVA: OSA 5405 I/O (indoor/outdoor)

Can be installed on windows or inside walls. Whether mounted indoors or outdoors, even at street level in urban canyons, OSA 5405 offers unparalleled flexibility.
OSA 5405 indoor installation
OSA 5405 outdoor installation
Exceptional characteristics are as follows:
  • Low-cost synchronisation source<
  • Small form factor (PTP-GM and GNSS receiver in one device)
  • Robust version
  • Combined optical fibre/copper-Ethernet interface
  • Power supply via PoE
  • Better indoor signal
  • Optional external antenna input<
  • Little space required when mounted on windows or walls
  • GPS, GLONASS, BeiDou and Galileo
  • Patented dual receiver algorithm
  • PTP grandmaster

ADVA: OSA 5401

SFP-based PTP grandmaster, boundary and slave clock designed for use in packet networks, allowing you to upgrade legacy systems with IEEE l588v2 PTP and synchronous Ethernet functionality.
OSA 5401
Exceptional characteristics are as follows:
  • Low OPEX and CAPEX
  • Miniature form factor, can be plugged into existing equipment
  • Easy to install and operate
  • Low power consumption < 1.5 W<
  • High performance
    • 100 ns accuracy (compared with UTC)
    • :temperature range -40 to +80°C
    • supports PTP (1588v2) and SyncE

ADVA: OSA 3300/50 optical cesium clock

Highly accurate optical caesium reference oscillator for superior frequency stability.
OSA 3300/50 optical cesium clock
Exceptional characteristics are as follows:
  • Superb accuracy due to optical scanning
    • 10 x more stable than magnetic scanning
    • Frequency stability < +/- 1 x 10-12 (OSA3350)
    • 2 x longer product life

ADVA: Ensemble controller and Sync Director

The ADVA Ensemble controller network management system with its additional Sync Director software package enables easy management of OSA devices in the synchronisation network topology.
ADVA: Ensemble controller and Sync Director
Exceptional characteristics are as follows:
  • Topology and synchronisation network are displayed
  • Active/passive clock paths are shown in the whole network
  • Real-time status information of master, boundary and slave clocks is displayed
  • Clock quality throughout the network is displayed