Re: Time and Timing Servers

[Mike Hammett <nanog () ics-il net>]

I'll look into Meinberg. 


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. 







----- 
Mike Hammett 
Intelligent Computing Solutions 

Midwest Internet Exchange 

The Brothers WISP 

----- Original Message -----

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