Spectracom SecureSync Product information sheet

SecureSync®
Time and Frequency
Synchronization System
User Reference Guide
Document Part No.: 1200-5000-0050
Revision: 18
Date: May12, 2015
www.spectracomcorp.com

© 2009-2015 Spectracom, Inc. All rights reserved.
The information in this document has been carefully reviewed and is believed
to be accurate and up-to-date. This User Reference Guide is subject to
change without notice. For the most current version of this documentation,
please see our web site at www.spectracomcorp.com.
Spectracom reserves the right to make changes to the product described in
this document at any time and without notice. Any software that may be
provided with the product described in this document is furnished under a
license agreement or nondisclosure agreement. The software may be used or
copied only in accordance with the terms of those agreements.
No part of this publication may be reproduced, stored in a retrieval system, or
transmitted in any form or any means electronic or mechanical, including pho-
tocopying and recording for any purpose other than the purchaser's personal
use without the written permission of Spectracom, Inc.
Other products and companies referred to herein are trademarks or registered
trademarks of their respective companies or mark holders.
Spectracom Corp.
• 1565 Jefferson Road, Suite 460, Rochester, NY 14623 USA
• 3, Avenue du Canada, 91974 Les Ulis Cedex, France
• 6A Beechwood Chineham Park, Lime Tree Way, Basingstoke, Hampshire RG24 8WA, United Kingdom
• Room 208 , No. 3 Zhong Guan Village South Road, Hai Dian District, Beijing 100081, China
Questions or comments regarding this User Reference Guide?
èE-mail: [e-mail]
SecureSync User Reference Guide I

Five Year Limited Warranty
Spectracom, a business of the Orolia
Group, warrants each new standard
product to be free from defects in material,
and workmanship for five years after ship-
ment in most countries where these
products are sold, EXCEPT AS NOTED
BELOW (the “Warranty Period” and "Coun-
try Variances").
Warranty Exceptions
This warranty shall not apply if the product
is used contrary to the instructions in its
manual or is otherwise subjected to mis-
use, abnormal operations, accident, light-
ning or transient surge, or repairs or
modifications not performed by Spec-
tracom authorized personnel.
Items with a variance to the Five Year War-
ranty Period are as follows:
90 Days Warranty
TimeKeeper Software
One Year Limited Warranty
Timeview Analog Clock
Path Align-R Products
Bus-level Timing Boards
IRIG-B Distribution Amplifiers
Two Year Limited Warranty
Rubidium Oscillators
Epsilon Board EBO3
Epsilon Clock 1S, 2S/2T, 3S, 31M
Epsilon SSU
Power Adaptors
Digital and IP/POE Clocks
WiSync Wireless Clock Systems and
IPSync IP Clocks
Rapco 1804, 2804, 186x, 187x, 188x,
189x, 2016, 900 series
Three Year Limited Warranty
Pendulum Test & Measurement Products
GPS- 12R, CNT- 9x, 6688/6689, GPS-
88/89, DA-35/36, GPS/GNSS Simulators
Country Variances
All Spectracom products sold in India have
a one year warranty.
Warranty Exclusions
Batteries, fuses, or other material con-
tained in a product normally consumed in
operation.
Shipping and handling, labor & service
fees EXCEPT FOR THE LIMITED
WARRANTY STATED ABOVE,
SPECTRACOM DISCLAIMS ALL
WARRANTIES OF ANY KIND WITH
REGARD TO SPECTRACOM PRODUCTS
OR OTHER MATERIALS PROVIDED BY
SPECTRACOM, INCLUDING WITHOUT
LIMITATION ANY IMPLIED WARRANTY
OR MERCHANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE.
Spectracom shall have no liability or
responsibility to the original customer or
any other party with respect to any liability,
loss, or damage caused directly or indir-
ectly by an Spectracom product, material,
or software sold or provided by Spec-
tracom, replacement parts or units, or ser-
vices provided, including but not limited to
any interruption of service, excess charges
resulting from malfunctions of hardware or
II SecureSync User Reference Guide
SPECTRACOM LIMITED WARRANTY

software, loss of business or anti-
cipatory profits resulting from the use
or operation of the Spectracom
product or software, whatsoever or
howsoever caused. In no event shall
Spectracom be liable for any direct,
indirect, special or consequential dam-
ages whether the claims are grounded
in contract, tort (including negligence),
or strict liability.
Extended Warranty Cover-
age
Extended warranties can be pur-
chased for additional periods beyond
the standard warranty. Contact Spec-
tracom no later than the last year of
the standard warranty for extended
coverage.
Warranty Claims
Spectracom’s obligation under this
warranty is limited to the cost of in-fact-
ory repair or replacement, at Spec-
tracom’s option, of the defective
product or the product’s defective com-
ponent. Spectracom’s Warranty does
not cover any costs for installation,
reinstallation, removal or shipping and
handling costs of any warranted
product. If in Spectracom’s sole judg-
ment, the defect is not covered by the
Spectracom Limited Warranty, unless
notified to the contrary in advance by
customer, Spectracom will make the
repairs or replace components and
charge its then current price, which the
customer agrees to pay.
In all cases, the customer is respons-
ible for all shipping and handling
expenses in returning product to Spec-
tracom for repair or evaluation. Spec-
tracom will pay for standard return
shipment via common carrier.
Expediting or special delivery fees will
be the responsibility of the customer.
Warranty Procedure
Spectracom highly recommends that
prior to returning equipment for ser-
vice work, our technical support depart-
ment be contacted to provide
troubleshooting assistance while the
equipment is still installed. If equip-
ment is returned without first con-
tacting the support department and
“no problems are found” during the
repair work, an evaluation fee may be
charged.
Spectracom shall not have any war-
ranty obligations if the procedure for
warranty claims is not followed. Cus-
tomer must notify Spectracom of a
claim, with complete information
regarding the claimed defect. A Return
Authorization (RMA) Number issued
by Spectracom is required for all
returns.
Returned products must be returned
with a description of the claimed
defect, the RMA number, and the
name and contact information of the
individual to be contacted if additional
information is required by Spectracom.
Products being returned on an RMA
must be properly packaged with trans-
portation charges prepaid.
SecureSync User Reference Guide III

IV SecureSync User Reference Guide

CONTENTS
SecureSync User Reference Guide • TABLE OF CONTENTS V
CHAPTER 1
Introduction & Overview 1
1.1 Getting Started 2
1.2 Introduction 2
1.3 Inputs and Outputs 3
1.4 General Information about GPS and GNSS 3
1.5 Front Panel 4
1.6 Front Panel Status LEDs 4
1.7 Rear Panel 6
1.8 Specifications 8
1.8.1 GNSS Receiver 8
1.8.2 RS-232 Serial Port 8
1.8.3 10/100 Ethernet Port 9
1.8.4 Protocols Supported 9
1.8.5 1PPS Output 9
1.8.6 10 MHz Output 9
1.8.7 Input Power 10
1.8.8 Fuses 10
1.8.9 Mechanical and Environmental Specifications 11
1.9 Regulatory Compliance 12
CHAPTER 2
INSTALLATION 15
2.1 Installation and Setup Summary 16
2.2 Main Installation Steps 16
2.3 Unpacking and Inventory 17
2.4 Required Tools and Parts for Installation 18
2.5 SAFETY 18
2.5.1 Safety: Symbols Used 18

2.5.2 SAFETY: Before You Begin Installation 19
2.5.3 SAFETY: User Responsibilities 21
2.5.4 SAFETY: Other Tips 21
2.6 Rack Mounting 22
2.6.1 Desktop Operation 23
2.7 Power Connection 23
2.7.1 Input Power Selection 23
2.7.2 Using AC Input Power 24
2.7.3 Using DC Input Power 24
2.8 Connecting Reference Input(s) and Network Interface(s) 25
2.8.1 Connecting GNSS Input 26
2.8.2 Connecting IRIG Input 26
2.8.3 Ethernet Connection 26
2.9 Powering up the Unit 27
2.10 Using the Keypad and Information Display 28
2.10.1 Keypad Description 28
2.10.2 Navigating the Information Display 29
2.10.3 Keypad Menu Tree 29
2.10.4 Unlocking the Front Panel Keypad 30
2.11 DHCP Network Configuration 30
2.11.1 Opening the WebUI 30
2.11.2 Replacing a Dynamic with a Static IP Address 31
2.12 Network Configuration Without DHCP 32
2.12.1 Assigning a Static IP Address 32
2.12.2 Network Configuration via Front Panel 33
2.12.3 Network Configuration via Serial Port 34
2.13 Typical Post-Installation Configurations 36
2.13.1 Displaying Local Time 36
2.13.2 Synchronizing Network PCs 36
2.14 Product Registration 36
CHAPTER 3
CONFIGURATION 39
3.1 Product Configuration via the WebUI 41
VI SecureSync User Reference Guide • TABLE OF CONTENTS

3.1.1 The Main Screen of the WebUI 41
3.1.2 Accessing Setup Pages via the MANAGEMENT Menu 43
3.2 Default and Recommended Configurations 44
3.3 NETWORK Setup Pages 44
3.3.1 General Setup 45
3.3.2 Configuring Ethernet 46
3.3.3 Network Services: En-/Disabling 63
3.3.4 Configuring HTTPS 64
3.3.5 Configuring SSH 74
3.3.6 System Time Message 83
3.3.7 Configuring SNMP and Notifications 85
3.4 Network Time Protocol (NTP) 95
3.4.1 The NTP Setup Screen 95
3.4.2 NTP Servers & Peers (Stratum Synchronization) 98
3.4.3 NTP Output Timescale 101
3.4.4 NTP Timing System: Reference Selection and Preference 102
3.4.5 NTP Keys 103
3.4.6 NTP over Anycast 105
3.4.7 NTP Expert Mode 108
3.4.8 Spectracom Technical Support for NTP 110
3.4.9 NTP Servers: Adding, Configuring, Deleting 111
3.4.10 NTP Peers: Adding, Configuring, Deleting 113
3.4.11 Configuring NTP Symmetric Keys (MD5 Authentication) 114
3.4.12 Configuring NTP Access Restrictions 117
3.4.13 Viewing NTP Clients 119
3.4.14 Restoring the Default NTP Configuration 120
3.4.15 Enabling and Disabling NTP 120
3.4.16 Enabling/Disabling NTP Broadcasting 120
3.4.17 Configuring NTP Autokey 121
3.4.18 NTP Stratum Configuration 123
3.5 Configuring TimeKeeper 126
3.5.1 Has TimeKeeper been activated? 126
3.5.2 Configuring a TimeKeeper PTP Master 127
3.5.3 Configuring TimeKeeper PTP Slaves 130
SecureSync User Reference Guide • TABLE OF CONTENTS VII

3.5.4 Configuring TimeKeeper as an NTP Time Server 132
3.6 OTHER Setup Pages 134
3.6.1 Authentication 134
3.6.2 Managing Password Security 137
3.6.3 Configuring LDAP Authentication 138
3.6.4 RADIUS Authentication 142
3.6.5 Input Reference Priorities 148
3.6.6 Notifications 157
3.6.7 System Time 164
3.6.8 Front Panel Configuration 178
3.6.9 Backing-up and Restoring Configuration Files 182
3.6.10 Oscillator Disciplining 188
3.6.11 Holdover Mode 195
3.6.12 1PPS and 10MHz Outputs 197
3.6.13 Signature Control 201
3.6.14 The GNSS Reference 202
3.6.15 Configuring the GNSS Receiver 205
3.6.16 Viewing the Status of a GNSS Reference 211
3.7 The Administrator Login Password 215
3.7.1 Resetting the Administrator Password When Forgotten/Lost 216
3.8 Resetting the Unit to Factory Configuration 218
3.8.1 Resetting All Configurations to their Factory Defaults 218
3.8.2 Resetting the GNSS Receiver Position 219
3.8.3 Clearing Locally Stored Logs: All Files 221
3.8.4 Clearing Locally Stored Logs: Selected Files 222
3.9 Issuing the HALT Command Before Removing Power 222
3.9.1 Issuing HALT Command via the Web UI 223
3.9.2 Issuing HALT Command via Keypad/SerialPort/Telnet/SSS 224
3.10 Rebooting the System 224
3.10.1 Rebooting via LCD/Keypad, Serial Port, Telnet, SSH, SNMP 225
3.11 If a Secure Unit Becomes Inaccessible 225
CHAPTER 4
OPERATION 227
VIII SecureSync User Reference Guide • TABLE OF CONTENTS

4.1 Status Monitoring via Front Panel LEDs 228
4.2 Front Panel Status LEDs 228
4.3 Status Monitoring via the Web UI 230
4.3.1 Status Monitoring on the HOME Screen 230
4.4 Status Monitoring of Input References 232
4.5 TimeKeeper™ 234
4.5.1 What is TimeKeeper? 234
4.5.2 What can TimeKeeper do for me? 234
4.5.3 Using TimeKeeper – First Steps 234
4.5.4 En-/Disabling TimeKeeper 235
4.5.5 Status Monitoring with TimeKeeper 236
4.6 Editing the Settings of an Input Reference 239
4.7 Outputs Status Monitoring 240
4.7.1 Monitoring the Status of All Outputs 240
4.7.2 Monitoring all Outputs of one Type 241
4.7.3 Displaying Output Settings 242
4.8 Editing Output Settings 243
4.9 Monitoring the Status of Option Cards 245
4.9.1 Monitoring the Status of ALL Option Cards 245
4.9.2 Monitoring the Status of a SPECIFIC Option Card 246
4.9.3 Monitoring an Option Card’s References and Outputs 247
4.10 NTP Status Monitoring 249
4.10.1 The NTP Time Offset Performance Graph 250
4.10.2 The NTP Frequency Offset Performance Graph 252
4.10.3 The NTP Jitter Performance Graph 253
4.11 Logs 255
4.11.1 Types of Logs 255
4.11.2 Local and Remote Logs 259
4.11.3 The Logs Screen 260
4.11.4 Displaying Individual Logs 261
4.11.5 Saving and Downloading Logs 263
4.11.6 Configuring Logs 265
4.11.7 Setting up a Remote Log Server 268
SecureSync User Reference Guide • TABLE OF CONTENTS IX

4.11.8 Restoring Log Configurations 271
4.11.9 Clearing Logs 272
4.12 Leap Second Occurrence 272
4.12.1 Reasons for a Leap Second Correction 272
4.12.2 Leap Second Alert Notification 273
4.12.3 Leap Second Correction Sequence 274
4.13 Upgrades and Licenses 274
4.13.1 Software Updates 274
4.13.2 Applying a License File 276
4.14 Show Clock 277
CHAPTER 5
Option Cards 279
5.1 Option Cards Quick Reference Guide 280
5.1.1 Option Cards Overview 280
5.1.2 Option Card Identification 283
5.1.3 Connectors 286
5.1.4 Web UI Navigation: Option Cards 288
5.1.5 Viewing the Configuration of an Input or Output 288
5.1.6 Configuring the Settings of an Input or Output 290
5.1.7 Viewing the Signal State of an Input or Output 291
5.1.8 Verifying the Validity of an Input Signal 292
5.2 Time and Frequency Option Cards 292
5.2.1 1PPS Out [1204-18, -19, -21, -2B] 293
5.2.2 1PPS In/Out [1204-28, -2A] 297
5.2.3 1PPS In/Out, 10MHz In [1204-01, -03] 302
5.2.4 Frequency Out [1204-08, -1C, -26] 309
5.2.5 Programmable Frequency Out [1204-13, -2F, -30] 313
5.2.6 Programmable Square Wave Out [1204-17] 317
5.2.7 Simulcast (CTCSS/Data Clock) [1204-14] 321
5.3 Telecom Option Cards 328
5.3.1 T1/E1 Out [1204-09, -0A] 328
5.4 Time Code Option Cards 333
5.4.1 IRIG Out [1204-15, -1E, -22] 333
XSecureSync User Reference Guide • TABLE OF CONTENTS

5.4.2 IRIG In/Out [1204-05, -27] 338
5.4.3 STANAG Out [1204-11, -25] 351
5.4.4 STANAG In [1204-1D, -24] 358
5.4.5 HAVE QUICK Out [1204-10, -1B] 365
5.4.6 HAVE QUICK In/Out [1204-29] 370
5.4.7 ASCII Time Code In/Out [1204-02, -04] 376
5.5 Network Interface Option Cards 386
5.5.1 Gigabit Ethernet [1204-06] 387
5.5.2 PTP Grandmaster [1204-32] 388
5.5.3 PTP Master/Slave [1204-12] 402
5.6 Miscellaneous Option Cards 417
5.6.1 Alarm Relay Out [1204-0F] 417
5.6.2 Revertive Selector Card [1204-2E] 420
5.6.3 Event Broadcast [1204-23] 421
5.6.4 Bi-Directional Communication, RS-485 [1204-0B] 430
5.7 Option Card Field Installation Guide 432
5.7.1 Introduction 432
5.7.2 Outline of the Installation Procedure 433
5.7.3 Safety 433
5.7.4 PROCEDURE1: Unpacking 433
5.7.5 PROCEDURE2: Saving Refererence Priority Configuration 434
5.7.6 PROCEDURE3: Determining the Correct Installation Procedure 434
5.7.7 PROCEDURE4: Bottom Slot Installation 436
5.7.8 PROCEDURE5: Top Slot Installation, Bottom Slot Empty 436
5.7.9 PROCEDURE6: Top Slot Installation, Bottom Slot Occupied 438
5.7.10 PROCEDURE7: Frequency Output Cards: Wiring 439
5.7.11 PROCEDURE8: Gb ETH Card Installation, Slot1 Empty 440
5.7.12 PROCEDURE9: Gb ETH Card Installation, Slot1 Occupied 441
5.7.13 PROCEDURE10: Alarm Relay Card, Cable Installation 442
5.7.14 PROCEDURE11: Verifying Successful Installation 443
5.7.15 PROCEDURE12: Restoring Reference Priority Configuration
(optional) 444
SecureSync User Reference Guide • TABLE OF CONTENTS XI

CHAPTER 6
Troubleshooting 445
6.1 Troubleshooting: System Configuration 446
6.1.1 System Troubleshooting: Browser Support 446
6.2 Troubleshooting Using the Status LEDs 446
6.2.1 Minor and Major Alarms 448
6.3 Troubleshooting – Unable to Open Web UI 448
6.4 Troubleshooting via Web UI Status Page 449
6.5 Troubleshooting GNSS Reception 451
6.6 Troubleshooting – Keypad Inoperative 451
6.7 Troubleshooting – 1PPS, 10 MHz Outputs 452
6.8 Troubleshooting – Blank Information Display 452
6.9 Troubleshooting the Front Panel Serial Port 453
6.10 Troubleshooting the Front Panel Cooling Fan 454
6.11 Troubleshooting – Network PCs Cannot Sync 454
CHAPTER 7
Command-Line Interface 455
7.1 Setting up a Terminal Emulator 456
7.2 CLICommands 457
APPENDIX
Appendix 463
8.1 ASCIITime Code Data Formats 464
8.1.1 NMEA GGA Message 464
8.1.2 NMEA RMC Message 465
8.1.3 NMEA ZDA Message 465
8.1.4 Spectracom Format 0 466
8.1.5 Spectracom Format 1 467
8.1.6 Spectracom Format 1S 469
8.1.7 Spectracom Format 2 470
8.1.8 Spectracom Format 3 472
8.1.9 Spectracom Format 4 474
XII SecureSync User Reference Guide • TABLE OF CONTENTS

8.1.10 Spectracom Format 7 475
8.1.11 Spectracom Format 8 477
8.1.12 Spectracom Format 9 478
8.1.13 BBC Message Formats 479
8.1.14 GSSIP Message Format 484
8.1.15 EndRun Formats 485
8.2 IRIG Standards and Specifications 487
8.2.1 IRIG Carrier Frequencies 487
8.2.2 IRIG B Output 491
8.2.3 IRIG E Output 495
8.2.4 IRIG Output Accuracy Specifications 499
8.3 Technical Support 500
8.3.1 Regional Contact 500
8.4 Return Shipments 501
8.5 License Notices 501
8.5.1 NTPv4.2.6p5 501
8.5.2 OpenSSH 506
8.5.3 OpenSSL 510
8.6 List of Tables 514
8.7 List of Images 515
8.8 Document Revision History 517
INDEX
SecureSync User Reference Guide • TABLE OF CONTENTS XIII

BLANK PAGE.
XIV SecureSync User Reference Guide • TABLE OF CONTENTS

CHAPTER 1•SecureSync User Reference Guide 1
CHAPTER 1
Introduction & Overview
The Chapter presents an overview of the SecureSync Time and Fre-
quency Synchronization System, its capabilities, main technical fea-
tures and functions.
The following topics are included in this Chapter:
1.1 Getting Started 2
1.2 Introduction 2
1.3 Inputs and Outputs 3
1.4 General Information about GPS and GNSS 3
1.5 Front Panel 4
1.6 Front Panel Status LEDs 4
1.7 Rear Panel 6
1.8 Specifications 8
1.8.1 GNSS Receiver 8
1.8.2 RS-232 Serial Port 8
1.8.3 10/100 Ethernet Port 9
1.8.4 Protocols Supported 9
1.8.5 1PPS Output 9
1.8.6 10 MHz Output 9
1.8.7 Input Power 10
1.8.8 Fuses 10
1.8.9 Mechanical and Environmental Specifications 11
1.9 Regulatory Compliance 12

1.1 Getting Started
Welcome to this User Reference Guide for your SecureSync unit. Whether you read this online, on
paper, or in a pdf document, we sincerely hope you'll quickly find your way around.
Depending on what your objective is today, here are our recommendations on what to do next:
If you want to install and configure aSecureSync, and have no or little experience with this
technology, we suggest you
a. browse through CHAPTER1 first, and then
b. familiarize yourself with the installation procedure and its variations—see "Install-
ation and Setup Summary" on page16.
If you plan on installing aSecureSync unit and you are familiar with the basic technical con-
cepts of time and frequency synchronization, as well as network administration, we sug-
gest you start here:
"Installation and Setup Summary" on page16.
If your unit is up and running, and you consider changing a specific setting—or learning more
about its features and functions—the easiest way to find the information you are looking for
is
the TABLEOFCONTENTS, or
the INDEX.
Should you experience technical problems, refer the following information sources:
a. "Troubleshooting" on page445
b. "INDEX" on pagei
c. Spectracom Online Knowledge Base
d. "Technical Support" on page500.
1.2 Introduction
SecureSync®is a security-hardened network appliance designed to meet rigorous network secur-
ity standards and best practices. It ensures accurate timing through multiple references, tamper-
proof management, and extensive logging. Robust network protocols are used to allow for easy
but secure configuration. Features can be enabled or disabled based on your network policies.
Installation is aided by DHCP (IPv4), AUTOCONF (IPv6), and a front-panel keypad and LCD dis-
play.
The 1-rack unit high (1RU) chassis supports GNSS input (SAASM GPS receivers, supporting
L1/L2, available for authorized users and required for the US DoD are available), IRIG input and
other input references. The unit is powered by AC on an IEC60320 connector. DC power as back-
up to AC power, or as the primary input power source, is also available.
2CHAPTER 1•SecureSync User Reference Guide Rev.18
1.1 Getting Started

SecureSync combines Spectracom’s precision master clock technology and secure network-cent-
ric approach with a compact modular hardware design to bring you a powerful time and frequency
reference system at the lowest cost of ownership. Military and commercial applications alike will
benefit from its extreme reliability, security, and flexibility for synchronizing critical operations.
An important advantage of SecureSync is its unique rugged and flexible modular chassis that can
be configured for your specific needs. Built-in time and frequency functions are extended with up to
six input/output modules.
Included with the base unit is an extremely accurate 1PPS timing signal aligned to a 10 MHz fre-
quency signal. A variety of internal oscillators is available, depending on your requirements for hold-
over capability and phase noise. Choose from a variety of configurable option cards, each with an
assortment of input/output timing signal types and quantity, including additional 1PPS, 10 MHz,
timecode (IRIG, ASCII, HAVE QUICK), other frequencies (5MHz, 2.048 MHz, 1.544MHz,
1MHz), Precision Timing Protocol (PTP) input/output, multi-Gigabit Ethernet (10/100/1000Base-
T), telecom T1/E1 data rates and multi-network NTP, allowing SecureSync to be customized for
your exact requirements.
To support network time synchronization, SecureSync supports the latest features of Network
Time Protocol (NTP). An optional multi-port NTP configuration allows for operation across four
LAN segments or shared operation between up to four separate/isolated networks.
NOTE – All features described are not available on all SecureSync variants.
1.3 Inputs and Outputs
SecureSync provides multiple outputs for use in networked devices and other pieces of tech-
nology. A 1-Pulse-Per-Second (1PPS) output acts as a precise metronome, counting off seconds
of System Time in the selected timescale (such as UTC, TAI or GPS). A 10MHz frequency ref-
erence provides a precise, disciplined signal for control systems and clocks (as the inverse of time
is frequency). SecureSync's outputs are driven by its inputs – most significantly, Global Navigation
Satellite System (GNSS) technology as well as IRIG input from IRIG signal generators (such as
Spectracom’s NetClocks and bus- level timing boards) and other available input references.
GNSS-equipped SecureSyncs can track up to thirty-two GNSS satellites simultaneously and syn-
chronize to the satellite’s atomic clocks. This enables SecureSync-equipped computer networks
to synchronize all elements of network hardware and software (including system logs) over LANs
or WANs – anywhere on the planet.
1.4 General Information about GPS and GNSS
The United States government operates a set of approximately 32 satellites, collectively known as
the "GPS Constellation" or "GPS Satellites." Each satellite has an internal atomic clock and trans-
mits a signal specifying the time and satellite position. On the ground, the GPS receiver determ-
ines its position (longitude, latitude and elevation) and the time by decoding the signals
simultaneously from at least four of the GPS satellites. Each satellite transmits a CDMA signal in
1.3 Inputs and Outputs
CHAPTER 1•SecureSync User Reference Guide Rev.18 3

the L1 band at a frequency of 1575.42MHz. When power is first applied, the GPS receiver begins
searching for the satellites. It does this by searching for each satellite, individually, listening for
each satellite's distinct spread-spectrum hopping sequence. This process can take a few minutes,
as the receiver iteratively locates satellites, refines its position, and determines for which satellites
to search.
The GPS receiver retains the last known position when the power is switched off. This results in
faster satellite acquisition the next time it is switched on. If the antenna has been moved more than
a few miles, however, acquisition time will be slightly longer because it must first re-compute the
position.
Other global navigation systems (GNSS) can be used alongside, or instead of, GPS: The Russian
GLONASS system is fully operational with 24satellites each transmitting at a slightly different fre-
quency in the L1 band between 1598and 1606MHz. This GPS/GLONASS frequency diversity
offers some frequency diversity with GPS for improved performance in some environments when
using while allowing for dual-mode GPS+GLONASS receivers. Other benefits are system redund-
ancy and the availability of additional satellites available when using GPS and GLONASS
together.
1.5 Front Panel
The front panel of the SecureSync unit consists of three separate illuminated status LEDs, a front
panel control keypad, an LED time display, an LCD information display, an RS-232 serial inter-
face, and a temperature controlled cooling fan.
The LCD information display is configurable using the SecureSync Web browser user interface
(also referred to as the “Web UI”) or the front panel controls. Display options include status or pos-
ition information, time, date, DOY (Day of Year), GNSS information, as well as network settings.
The RS-232 serial interface and the front panel controls provide a means of initially configuring the
unit’s network settings.
Figure 1-1: Front panel layout
1.6 Front Panel Status LEDs
The three status LEDs ("Front panel layout" above), POWER ,SYNC , and FAULT , indicate
whether SecureSync is synchronized, whether power is applied to the unit and if any alarms are
currently asserted.
4CHAPTER 1•SecureSync User Reference Guide Rev.18
1.5 Front Panel