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ISDN USERS: It's time to get a backup system

OK, some of you may see this is a thinly veiled way to boost sales of equipment or software.  If you can't be convinced otherwise, then stop reading now.  

Now, the rest of you smart people, here's my reasoning.

ISDN has been considered for over 15 years the gold standard for a voice actor's home studio connection to their client's studios.  When it was developed the Internet existed, but we had no broadband access in our homes.  At that time ISDN technology provided the fastest possible data connection mere mortals could access.  Along came audio codecs, hardware devices that take analog audio and squash it down to digital information that will fit down a 128kb/s pipe.  It worked well, it was state of the art, and many commercial and broadcast facilities invested in it.  

For 10 years ISDN was king of the mountain, with no chance of being knocked off.  But in the last five years high speed Internet access has become more ubiquitous, and new technologies have come along to dethrone the king.  The advantage of using an Internet based system has always been flexibility and cost, but not reliability.  It appears that the balance of reliability is starting to tip from ISDN to Internet.  

My theory is based on a few factors.  As of late more and more of my ISDN using clients are complaining of stability issues, dropouts, horrible blasts of noise, and increasing support challenges and costs for installation and monthly service.  The TelCos, in the Los Angeles area Verizon and AT&T, clearly don't have ISDN users high on the priority list.  Ordering the service is becoming impossible in some areas, finding someone to talk to when service outages occur is painful, and monthly rates only go up.   Call at TelCo to order ISDN and you'll see where the acronym's interpretation "I Still Don't Know" came from.  It's just not profitable enough for TelCos to promote the use of ISDN any longer, and it shows.  

ISDN requires special systems to be in place outside of the user's building.  It appears in the wall like a standard phone line, but what happens once that copper wire reaches the pole is completely unique to this system.  There are network cards and switches that have been in service for many years, some of them completely dormant for extended periods due to a lack of user base.  At least half of the orders I've had placed for ISDN have needed repair immediately upon fullfilment to be functional.  These systems just get older and more neglected over the years, while the Internet backbone receives the focus and funding.  It also seems more commonplace and accepted that ISDN codecs need to be rebooted and "futzed with" to get a reliable "lock" with the other user.  We just get used to this over time, but there really should be no reason we have to deal with this.  

Those of you who would be seriously put out if you lost ISDN service for more than a few hours, I seriously recommend putting a backup system in place.  The technology that has done the most to establish itself in the voiceover industry as an ISDN alternative is Source Connect.  For under $700 with iLok USB key you can install this software on any of your Windows or Mac computers.  There are no monthly charges, no install charges, no long distance, and no per-minute fees when you connect to another Source Connect user. Even if you don't use it for 6 months, that one time you use it to bail out an ISDN fail will pay for itself immediately.   If you are lucky enough to work with a Source Connected studio, be prepared for how incredible it sounds compared to ISDN!  

There are a few catches to using Source Connect to replace ISDN.  First, it can't connect directly to an ISDN codec.  Internet and ISDN are completely independent of each other and don't speak the same language.  If the client you are working with only has ISDN, you'll need to employ the services of a "bridge".  One such service dubbed Out of Hear, created by DG Entertainment engineer Steve Nafshun, does nothing but ISDN bridging.  His studio has four Telos Zephyrs connected to four ISDN lines, and multiple Source Connect accounts always at the ready to make your connection.  Steve assigns you a pair of ISDN numbers to give your clients and agents, and a correlated Source Connect account.  If your ISDN service goes on the blink, or you want to travel away from the confines of ISDN availability, call Steve and he'll patch you through.  It's seamless for your ISDN using clients, only increasing the latency or delay by second or so.   

Second, it does require at least a 300 kb/s upload and download Internet connection of good quality.  While WIFI can work in the best of circumstances, Ethernet is highly recommended.  Some hotels may only provide WIFI, so this can put you at greater risk for signal drops.  Configuring the network may be required in some cases for a trouble free connection, but I've found it usually can make a connection without special setup like port mapping.    In my point of view these are small prices to pay for a system that can be used anywhere in the world, with only a mic, USB interface, and lightweight laptop computer.  

One of my clients, Pat Duke, decided to forgo installing ISDN completely when he relocated to Los Angeles a few years ago.  Check out this video of his recent appearance on East West Audio Body Shop, as he describes his home studio and experiences using Source Connect.



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Reader Comments (1)

ISDN was EOL (end of life) when I was using a Network General Sniffer to troubleshoot networks in the 90s and before I got back into doing VOs. The telcos have slowly been phasing ISDN out while squeezing out every last penny of ROI that they can. ISDN was never a best seller; it did a lot better in Europe than here. The key difference between ISDN and IP is simply reliability, speed has nothing to do with it really; ISDN is pretty slow and always has been. When you talk about IP the issue, it is more about capacity than speed. It is true that speed begets capacity, but that's a brandy & cigar conversation between network protocol analysts.

ISDN establishes a circuit between point A and point B. Once it is established, the earth has to move to rattle the connection (at least it used to be that way before the infrastructure started crumbling). IP networks do not establish connections the way ISDN does; the path between point A and point B can go from A to L to C to B for the first packet and go from A to Q to R to S to Z to Y to L to M to N to B for the second depending on network conditions. Each of those routers delay the arrival of a packet so that it is possible for the 3rd packet that only had 3 "hops" between A and B to arrive at destination B before the 2nd packet. Keep in mind that we're talking MILLIONS - maybe 10s of millions - of packets in a recording session over the Internet. The layer 3 IP protocol has two dominant layer 4 transport protocols: TCP or UDP. TCP is reliable, but the overhead is staggering, unfortunately I do not remember how many more packets it would add to a conversation of a million packets. The other transport protocol is UDP. It is unreliable. It shoots packets on to the Internet and doesn't give a hoot if the packet makes it from point A to point B. RTP, real time protocol, which was developed for audio and video transmissions generally uses UDP.

We all know that Skype has a really special VOIP system and proves there's hope for a top shelf, studio grade system. Skype's VOIP protocol is proprietary and I have never sniffed a Skype connection (I need to put that on my to-do list). ...but there's hope for those of us with studios in the remote Rocky Mountains :)

When I last spoke to the Source Connect people, I believe they told me that they used UDP as the transport layer protocol. What that means is that even with a more than adequate network connection, if the local telco has over-sold their available bandwidth (which they all try to do), the number of packets lost and the processing time required for packet reassembly in the destination router and then on the destination computer increases and degrades audio quality. And remember, at multiple stops along the path between point A and B the packets must traverse shared media where your packets must wait their turn before they get to go.

This is not simple technology. I've never used a Source Connect connection, but I'd bet that here in the Rockies, I'd experience great days, good days, and bad days depending upon the condition of the path from here to a studio in New York or LA.

Is Source Connect the future? It is a step into the future, but the future won't depend on UDP as a transport protocol; you can take that to the bank.

November 22, 2011 | Unregistered Commentersteve hammill
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