I recent thread mentioned high-sensitivity receivers often allow GPS to work inside. Obviously "inside" has a lot of definitions.
I will need this facility for the TDM timing signals. It's a central office, not a datacenter.
I don't know that Internet-based NTP would be accurate enough for the timing signals that I need. Maybe, maybe not.
From: "Majdi S. Abbas" <msa@latt.net>
To: "Mike Hammett" <nanog@ics-il.net>
Cc: nanog@nanog.org
Sent: Thursday, July 11, 2019 9:54:26 AM
Subject: Re: Time and Timing Servers
On Thu, Jul 11, 2019 at 09:29:46AM -0500, Mike Hammett wrote:
> There were a lot of NTP threads several weeks ago, but I didn't get an answer to my question amongst all of the other chatter.
>
> I'm looking for a device that can receive GPS inside a building without the
> assistance of an external antenna (Frontier says they no longer allow
> external antenna), will provide traditional NTP services, and will provide
> a timing signal that my Metaswitch can work with.
Unfortunately, L band satellite signals are incredibly weak by
the time they reach the surface. It's very unlikely this is going to
work for you (unless it's a wood framed single story building.)
Generally, I try to ensure that a GNSS antenna is built into the
contract, to avoid games like this.
You have two options:
A) Find a new colocation provider. This may already be on your
to-do list for other reasons.
B) Rely on the Internet for timing, using NTP or PTP from
another location to backfeed the site, and use a box with a good
stable oscillator to keep time (this can actually be a commercial
time server with decent holdover characteristics.
If you're just looking for alternatives to Microsemi, I highly
recommend talking to the fine folks at Meinberg.
--msa
To: "Mike Hammett" <nanog@ics-il.net>
Cc: nanog@nanog.org
Sent: Thursday, July 11, 2019 9:54:26 AM
Subject: Re: Time and Timing Servers
On Thu, Jul 11, 2019 at 09:29:46AM -0500, Mike Hammett wrote:
> There were a lot of NTP threads several weeks ago, but I didn't get an answer to my question amongst all of the other chatter.
>
> I'm looking for a device that can receive GPS inside a building without the
> assistance of an external antenna (Frontier says they no longer allow
> external antenna), will provide traditional NTP services, and will provide
> a timing signal that my Metaswitch can work with.
Unfortunately, L band satellite signals are incredibly weak by
the time they reach the surface. It's very unlikely this is going to
work for you (unless it's a wood framed single story building.)
Generally, I try to ensure that a GNSS antenna is built into the
contract, to avoid games like this.
You have two options:
A) Find a new colocation provider. This may already be on your
to-do list for other reasons.
B) Rely on the Internet for timing, using NTP or PTP from
another location to backfeed the site, and use a box with a good
stable oscillator to keep time (this can actually be a commercial
time server with decent holdover characteristics.
If you're just looking for alternatives to Microsemi, I highly
recommend talking to the fine folks at Meinberg.
--msa