Folks. I don't want to overstress the impact of the timing device.
YES, one is needed for conference, MOH (which is technically a bridge with the music file) and all other bridged calls. Can you time from the cpu itself?? YES. Will it necessarily be dependable -- NO. Will you definitely have problems -- NO A timing source is required for all PBX devices as they must conform to the Telcordia (formerly bellcore) standard as a DMS100 level (line side Class 5) device. Worst case scenario is enough delta 'T' to create abhorrent echo and finally a dropped call or two. Best case is that no one ever perceives a problem. Somewhere in the middle is the reality. When will the potential problems manifest themselves? NO WAY TO DETERMINE!! Here's why: There are millions of devices on the PSTN. Each telco device needs timing. They are SUPPOSED to be tied via BITS clock to the atomic clock signal embedded in the GPS signal. This doesn't always occur. Even when it DOES occur, internal problems on T1 smart Jacks, channel banks, M1-3 muxes, DNUS ports, gateway fiber muxes and a million other devices can cause timing slips. ALSO, many telco providers elect to use the T1 timing signal on their own facilities instead of buying the $150 BITS clock and $50 GPS antenna needed to interface. This means that the clock source they are using will actually introduce latency and on long T1 runs this can cause slips right at the LSO. The final result: Users may or may not perceive any quality problems based on their ear, length of phone calls, their mood that day, the moon phase, who won the ball-game and if they got luvin the night before. Don't sweat the timing source. Use a fairly reliable source and enjoy your system. When (IF) you experience problems, get a better timing source, have a few beers and relaxxxxxxxxxxxxxxxxxx! Simplifying the communications world Frank Perk Planet 3 Communications <http://maps.yahoo.com/py/maps.py?Pyt=Tmap&addr=2810+Sweet+Home+Road&csz=Amh erst%2C+NY+14228&country=us> 2810 Sweet Home Road Amherst, NY 14228 <mailto:[EMAIL PROTECTED]> [EMAIL PROTECTED] tel: fax: mobile: Skype ID: 716 929 VoIP (8647) x101 716 929 8648 716 430 6996 frankperk <https://www.plaxo.com/add_me?u=25770811418&v0=2003852&k0=1750959697> Add me to your address book... <http://www.plaxo.com/signature> Want a signature like this? _____ From: Mark Palser [mailto:[EMAIL PROTECTED] Sent: Friday, March 24, 2006 12:04 PM To: [EMAIL PROTECTED]; 'Reza - Asterisk Enthusiast'; 'TAUG' Subject: [on-asterisk] Re: **SPAM: RE: [on-asterisk] Timing Device Hardware (zaptel interfaces) and Software (ztdummy) I have just installed a 1U 3.0 GHz Xeon at a co-locate, just to provide a simple queue for some of our scheduling admins who are spread out across the country. The box is overkill, but I thought I might as well take advantage of the bandwidth and try and save the company some money on conference calling, we spend about $9000.00/yr at $0.13/min/caller. Does this mean I'm going to run into some problems if I rely on the ztdummy for timing? I only need to accommodate 4-16 people in a room at once, so far I've tested with 6 and it sounds fine, but we only stayed in the room for a few minutes. The box is a Dell 1850, I hear there might be a problem installing a Digium card/clone due to IRQ conflicts, that's if a card will even fit, didn't even give it a thought until I read this post, would welcome any advice, tips or suggestions, thanks, Mark. ----- Original Message ----- From: Frank Perk <mailto:[EMAIL PROTECTED]> To: 'Reza - <mailto:[EMAIL PROTECTED]> Asterisk Enthusiast' ; 'TAUG' <mailto:[email protected]> Sent: Friday, March 24, 2006 11:03 AM Subject: **SPAM: RE: [on-asterisk] Timing Device Hardware (zaptel interfaces) and Software (ztdummy) Reza: Yes, no POTS interfaces (Motorola chipset modems) can be used as a timing source. Any standard timing source can be used. Examples are: * BITS clock with GPS support * Telco timing (ie. T1, DS3) * SNTP Server (don't just specify it, build a simple clock routing based on the server) * Crystal oscillator * Synthesizer/multiplier It is impossible to clock off a device with no timing source, so just specifying the interface as the clock source without some legit source will create problems. Simplifying the communications world Frank Perk Planet 3 Communications <http://maps.yahoo.com/py/maps.py?Pyt=Tmap&addr=2810+Sweet+Home+Road&csz=Amh erst%2C+NY+14228&country=us> 2810 Sweet Home Road Amherst, NY 14228 <mailto:[EMAIL PROTECTED]> [EMAIL PROTECTED] tel: fax: mobile: Skype ID: 716 929 VoIP (8647) x101 716 929 8648 716 430 6996 frankperk <https://www.plaxo.com/add_me?u=25770811418&v0=2003852&k0=1750959697> Add me to your address book... <http://www.plaxo.com/signature> Want a signature like this? _____ From: Reza - Asterisk Enthusiast [mailto:[EMAIL PROTECTED] Sent: Thursday, March 23, 2006 5:35 PM To: 'TAUG' Subject: Re: [on-asterisk] Timing Device Hardware (zaptel interfaces) and Software (ztdummy) Hello Frank... granted no timing on POTS lines, but what about the FXO devices/cards itself? Everyone without an exception who I personally know running VOIP business - has an x100p/x101p or clone, or a TDM400P or a basic Sangoma A200 - even though not a single RJ-11 PSTN line is going into the cards. So does this mean the x100p/x101p/x100clones are irrelevant as a timing device for MeetMe & MoH functions? If this is irrelevant, how is the timing/synchronizing being done on my boxes where ztdummy was never compiled? Am I missing something critical and obviously silly, or am I opening a new can of worms? :). Cheers! Reza. ----- Original Message ----- From: Frank Perk <mailto:[EMAIL PROTECTED]> To: 'Reza - <mailto:[EMAIL PROTECTED]> Asterisk Enthusiast' ; 'TAUG' <mailto:[email protected]> Sent: Thursday, March 23, 2006 5:06 PM Subject: RE: [on-asterisk] Timing Device Hardware (zaptel interfaces) and Software (ztdummy) Reza: There is no timing on POTS lines. Only on T1 or higher.
