WWV Broadcast Outages

Royce Williams royce at techsolvency.com
Mon Mar 6 14:56:25 UTC 2017

On Mon, Mar 6, 2017 at 5:12 AM, Andrew Gallo <akg1330 at gmail.com> wrote:
> On 3/6/2017 3:55 AM, Majdi S. Abbas wrote:
>> On Wed, Feb 22, 2017 at 04:59:53AM -0800, Hal Murray wrote:
>>> Any suggestions for gear and/or software that works with WWV (or CHU)?
>>> Or general suggestions for non GPS sources of time?
>>         Hey Hal!
>>         In North America, WWV and CHU are pretty much it for accessible
>> backups these days.  Unfortunately time and frequency distribution is a
>> niche that tends to get neglected (if not actively gutted) in US
>> budgets.
> Agreed, but I'll share this- the recent FCC CSRIC V had a working group (4B) that studied the reliability of time and frequency distribution.
> https://www.fcc.gov/about-fcc/advisory-committees/communications-security-reliability-and-interoperability
> It may be of interest.

Specifically, the "Network Timing Single Source Risk Reduction - Final
Report" part:


My summary of its points:

* Analysis of vulnerabilities in the "supply chain" of GPS

* Assertion that GPS mitigations and alternatives are needed to reduce risk

* Some likely characteristics of good mitigations and alternatives

* A list of potential alternatives, their features, and their current
state (L2C & L5 GPS, Galileo & GLONASS, LEO satelltes, commercial RF,
antenna pattern optimization, NMA on L2C, sync over fiber, eLORAN,
other RF sync, terrestrial beacons, and hybrid DME)

>From the executive summary:

The U.S. communications sector relies heavily on the Global
Positioning System (GPS) to provide network time. GPS is a widely
available, extremely precise timing source that is used across
multiple infrastructure sectors. However, given the high dependence of
the communications sector on GPS, the Federal Communications
Commission (Commission) is interested in identifying ways to increase
the resilience of communications networks by exploring complementary
or backup solutions that could be employed to offer similar time
precision as GPS in the event that GPS signals are lost. These
solutions also need to be completely independent of GPS to
significantly reduce any risk. This report addresses the problems
associated with relying on GPS solutions, the ideal technical
characteristics for systems to backup or supplement GPS, and our
recommendations for possible backup solutions by the communications
industry and others reliant on communications network timing sources.


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