PBX for the Medical Office

Bruce gave me a hard time about the Switchvox review (yeh .. I’ll finish it) because there was no good introduction to exactly what the system is – and why I would want it.

 Here’s an intro paragraph:

Asterisk is an open-source phone system.  It replaces the Nortel or NEC or Siemens Or whatever system that you have in your office.

Why would you want to replace your current system?  Well .. because it’s old and hard to change settings and/or maybe it is just time to upgrage and you are shopping around.  In our case – it’s that the old system (a perfectly functional Nortel Meridian Sytem with Voicemail and ~10 extensions) didn’t do some thing that we wanted – and we’re tired of struggling with configuration changes that take either a long time to learn & memorize – or $90/hr to pay the local phone guys to come and help when we are over our heads.

Asterisk is great and has many features.  It does all of the things that your current phone system does .. like answer the phone .. route calls to extensions, manage voicemial, etc.  There are two things that make Asterisk different from most systems: 

  1. It usues VOIP
  2. It is free

The difference between a VOIP system and an analog system is that the voice is moved from the server to the phones over computer wires just like the signals from one computer to another.  Yes – it will work over WiFi too.  So of course the phones are not regular $9.99 phones you can pick up at Kmart .. they are actually little computers themselves – since they need to decode the bunches of data that represent the voice and make it into something that the person hears.  It all sounds like it would be too hard and too slow to do all of this encoding of data .. moving it and then decoding it .. but the technology has gotten pretty good.  Trust me – it works. Yes – you can even use the $9.99 phone from Kmart if you buy an ATA – which is a little adapter thing that costs about $60 and does the comptuer work for you.

Why would you want to use VOIP indtead of an analog system?  Using a computer to set-up the system and route the calls makes more sense than remembering (or reading) a bunch of codes and punching them into a telephone.  VOIP also means that the phones keep their setup information wherever they are.  So if you unplug the phone from the office and plug it back in at home (so long as you have an Internet connection) — the phone will work the same as it did at the office.  Dial a "local" extension for the person who was one office away and it will ring there just as if you had been back at work.

This makes it easy to have remote workers.  One of our nurses will be working from home to help us triage calls when we get too busy.  

Hardware and infrastructure needs.  To install a VOIP system – you really don’t need much.  Asterisk can run on an old PC with not-too much RAM.   The load on the server is proportional to the number of concurrent calls.  For home or small business – a reasonably capcable desktop PC would be fine.  Big companies can run hundreds fo concurrent calls through a moderately sized server.

The system needs to get calls .. and make calls – just like any phone system. 

If you want to use it at home, you could set it us with straight VIOP and pay for calls either monthly (unlimited minutes) or by the minute with Broadvoice or one of the other VOIP providers.  Google "Asterisk VOIP" and you’ll find lots.  You’ve heard of Vonage?  Well think of an Asterisk system as your own little Vonage.  Each extension you create in the system is like one of Vonage’s customers.

For a medical practice – VOIP may work for some things (we’re going to have a few lines on VOIP for overflow) but it’s better to connect the system to a T1 or partial T1 that is provided by your local phone company.  This will replace the analog lines that are plugged into your current system and will provide from 9 to 18 (depending on what you buy) lines.  The T1 connects to the Asterisk system (you have to buy a T1 card that goes into the computer for this – about $600), and Now Asterisk can "see " the lines from the phone company.  Calls from inside the system got out to the phone company .. and calls from outside come in.  You can set up rules for how calls are handled, set up "IVR trees" to help callers find what they want .. etc etc.

Still with me?

Ok .. so why use Switchvox instead of plain (free) asterisk?  Because The setup and management of Asterisk is not plug-and play.  I can do it ( I set up two Asterisk servers at home) and most nerds can – but I want something that our office manager can set up and manage without any technical help.  Switchvox is a commercial product that puts a plug-and-play user interface on top of Asterisk.  While there are other UI enhancements to Asterisk from competing vendors and open-source collaboratives, We selected Switchvox for the reasons I discuss in the review.  Switchvox costs about $1500.  Add the phones and you are probably talking about $3000 for the whole nine yards.  Compare that to a $10,000 or $20,000 phone system that does less.  Hmm .. hard choice — eh?

USb Flash Phone

Still thinking about how to outfit the office with phones for the new system (I don't want to spend a ton of $$ of Polycom phones for everyone! .. stumbled onto This Phone … which (I think) looks interesting, but I am thinkin that the Chinese => English translator needs a little work. The Q/A is funny to read. Esample:

1.Why I need order combo desktop package?

The combo desktop package will include one Telbox B2K and one USB phone P1K. You can install the Telbox B2K with your desk telephone, and use the USB phone P1K as your travel package. Also save your money.

Asterisk Review

Tom's Networking Product Reviews : TomsNetworking :

This is a very good overview of the asterisk at home project. I have been using asterisk for about eight or nine months. The at-home version of Asterisk makes it very easy to set up initially and learn how the system works. It's really extraordinary.

We are replacing our four year old telephone system in the office with a system based on Asterisk sometime in the next few weeks. We are waiting for the installation of our T1 line.

I am very excited because it will provide us an opportunity to enhance the services and make things go a little bit more smoothly in the office.

I'll write a quick review of the system tomorrow.

Apple iMac G5 – DOA & service troubles

Well . perhaps it was the OS 10.4 reviews (generally good) and the
trouble we had with editing movies with the crappy Windows software …
or I just wanted to see how the other side lived again (my 1st
computers were Macs .. and I lived over there on the "light side" for
!0 years before defecting in about 1995. 

So far, the next Mac decade isn't going so well.

The imac arrived today and Sam set it up in the family room.  All
was going OK until he called me in and suggested that I should help get
it to go on.

Everything was hooked together right, but it just wouldn't go on.

He said that it had powered up once and then "fell asleep." after about 30 seconds.

Subsequent efforts to get it on were unsuccessful.

That was about 10:00 PM

Apple Support is closed .. but they have "24 x 7 chat support" and an online troubleshooter.

I tried the troubleshooter while waiting for the online chat to
respond.  The troubleshooter was good, but I hit a dead end when
it told me to push a button that doesn't exist on my model.

So far – it looks like we are victims of the well-documented G5 imac
power supply issues.  But I think we have a world record for how
long the machine lasted.  (under 1 minute!)

Here's the transcript of my chat session with Apple — after waiting in their cue for 2 hrs:

Lingo VOIP, Time Servers, NTS, ReplayTV

If a purpose of a weblog is to document important things so that others can find them .. I'm obligated to share the following.  It's not medically related.  Medical readers please ignore this .. geeks are welcome to follow along for your reading pleasure.

Our home network has three replayTVs, a win2k server, an Iomega u300 270 GB NAS (RAID level 5) .. running through a Smoothwall Linux firewall, Linksys 24 port 10/100 switch,  a Lingo VOIP ATA and (finally) a Time Warner-supplied Toshiba cable modem .. which attaches us to Earthlink Broadband (essentially Time Warner RoadRunner).

I'll spare you the links to any of the above .. google will get you there rather easily.

We love the replayTVs as they allow us to avoid commercials.  We almost never watch "live TV" anymore.  We can also watch things when we want to – rather than when they are on.  Alias and West Wing are on at the same time, but we can alwasy see them.  Two weeks ago, we forgot to record Alias .. so I used Poopli to get it.  Cool.  We can also watch a show in the bedroom that was recorded in the Family Room.  Until …

Over the last few weeks, the replayTVs stopped reliably talking to each other.  Rebooting sometimes helped .. but I couldn't figure out what in the world was going on.

Last night I invested (wasted?) three hours and figured this all out.

After researching similar issues on the REplayTV FAQ and the AVS replyayTV forums, I learned that this problem is often due to the ReplayTVs having different TIME settings.  A difference of over 30 seconds is bad.

So I went through the processes that everyone suggested to cause the devices to "phone home" and find out from the ReplayTV mother ship what time it really is.  They're using a NTS protocol .. which runs on UDP port 123, BTW.

But none of the devices could get a new time!

So I looked at the firewall settings to amke sure that port 123 was open .. and it sure was ..

And then I looked in the firewall logs and saw that the poor firewall hadn't updated its time successfully in weeks.  Every time it tried to call a time server, it failed.

So I logged in to the Lingo ATA .. which was no small task.  I still can't get in with the admin password (thinking maybe that would have helped me to solve the problem .. so if anyone knows how .. let me know!) .. but the user password (username: user – password = ph3taswe) .. log in to through a browser .. and I noticed that the ATA has successfully made IP entries for DNS servers (it's getting DHCP from Roadrunner) but that it also has an entry for NTS .. which says "0" … so I'm guessing that the ATA is intercepting all NTS requests and sending them to the NTS that it knows about … which .. in this case .. is "0" .. so all NTS requests fail.

I'll bet that if I could get in to the admin interface, I could change the NTS address to something useful (it even looks like the Roadrunner DNS servers are running NTS) .. but I can't.

So at this point (1 AM last night) .. I had two choices:

a) Connect the firewall directly to the cable modem.  This would cause me to lose the QOS that the ATA presumably is giving me (though this may motivate me to add a QOS mod to the firewall).

b) Install NTS on the Win2Kserver .. and use the firewall to redirect all requests to UDP port 123 over to that server.  The time would be consistent within the network – even though they would not likely be "right" according to the Atomic clock.

I Chose option "a" since I want the ReplayTVs to work with Poopli . and I think that other ReplayTVs will need to be able to talk to mine .. so they will all need to agree on the time.

This option worked.  ReplayTVs now can tell the time, and Lingo phone quality doesn't seem too bad.  We'll see what happens when streaming TV shows across the network.


Scanning at home

At the office, we have great custon-built scanning software that Dave built.  It's worked flawlessly for 3 years now .. and aside from the fact that the TIFF files it makes are a bit bigger than they need to be (hin, hint Dave) … it's grrreat.

I'm looking for something now to use at home that is just as easy to use.  This is not rocket science .. so I'm surprised that no company has yet produced software that does this elegantly.  If you know of one .. please leave a comment.

The crieteria for a quick and easy scanning solution:


  • Easy to use
    • Really, really easy – this means that there is one button "scan" and perhaps a menu to define options such as resolution or turn on duplex, etc. 
  • Stores the files in folders in the OS (or FTP, I suppose) rather than a proprietary database
  • Provised optional annotation or indexing of files .. with either a database (ODBC connection preferred) or a text/XML file that is stored locally or on a network drive
  • Inexpensive.  This is not ricket science .. so we shouldn't pay for rocket science. 
  • Stores files efficiently – in TIFF or .pdf
  • Easy to use .. and really fast. 

What I've found so far:

edrawer - personal version is inexpensive .. but I can't download a demo .. and their website is so poorly designed it makes me wonder about their skills at making usable software.  I can't tell where the files are stored, but it looks like ley are ina database.  I don't want my files trapped in a database in 10 years.  I want them in the OS — in hierarchies of folders.  They won't be trapped when the scanning software company goes out of business and my software won't work in Windows 2015 .. or Windux .. or Mac OS XV.

PaperMaster.  hmm .. looks enticing,, but again .. where are the files?

SinmpleIndex "the best value in scanning software" .. sores files in folders.  Inexpensive.  Downloaded the demo.  Scans a few images just fine .. then .. crash .. over and over ..

If you want to make sales .. then make sure your demo works.

Douxplorer is a "document managerment systerm."  It works.  But it stores the files in the database .. which has to live on your hard drive .. unless you pay for the professional version (n which case you can store the "library" (databse) on a server or shared folder.

InfoThek Docudex is the winner so far .. as it seems to do everything I want .. and it's developed elegantly.  I'm going to test it for a while to see if I can make it work well.



"Bandwidth" is the amount of data a website consumes/generates/requires over a given period of time.  Since building Medlogs.com, the bandwidth consumed by my account on our web host has increased quite a bit.  How ironic that a successful weblog or public service site like Medlogs will cost (rather than earn) the owner more money.

Last month (october, 2004) we used nearly 12 GB of bandwidth … and one morning our sites were down because we had gone over the limit of 10 GB.  So today I'm experimenting with gzip compression to improve the speed of page downloads on both Medlogs and Docnotes.  There are several ways to enable gzip, but the simplest is to use php:

At the beginning of every document (or add it to the MoveableType template) insert this line:


Of course, if it's already a php document, you can omit the <?php … ?>

This will imporve performance on Medlogs.com and will reduce the amount of bandwidth that we use.

Blogrank.org is coming soon too 😉

Gmail, google, etc.

IT digest discusses the present and future of google. 

Here's my idea for another feature .. which I'll bet wouldn't be too hard to implement:

"publish this" in gmail would be a way to publish an e-mail to a weblog.  It would need to support a publishing API so we're not all locked in to blogger.  

oh .. I've got a few gmail invites .. if you want one, post a comment here.

I'll get back to medicine soon.