Choosing Phone Systems

Work in Progress.

In todays modern world of telecom, the process of choosing phone systems is as relevant as with any technology. It’s not about the brand name or what it can do, its what you want out of the system.  This isn’t just limited to telecom, its for everything. There are 9 bullet points, broken out by technology, user type and solutions

User Types

Hobbyist the amateur who doesn’t’ want to admit he is one, but wants to come off as an admin wannebee but strugles to get his foot in the door. Or he likes phone systems when he’s not busy with other things. If you’re the guy or girl who likes to focus on fine motor skills, you might want to look at TDM systems as that requires detailed and specific wiring. If you aren’t up to that skill but love to code, a VOIP solution would be the best fit if you know some UNIX or TCP/IP.

A Startup or small business: The user who will have less than 20 employees

The Enterprise: A company ranging from 200 to tens of thousands of employees.



Voice over IP (VOIP)

The fashionable standard of voice communications, using the defacto computer networking standard called Transmission Control Protocol/Internet Protocol or TCP/IP. Once used by nerds who had too much time on their hands, its become a reliable protocol and is accepted in the enterprise. Advantages include sharing a data network to allow voice traffic to be routed around; allegedly lowers costs; and allegedly gives more options for the customer. Disadvantages include if you don’t know networking, you may need a crash course. Also the Internet or IP does live up to its literal synonym called “cyberspace.” Most of the routing and switching is based on IP addresses, MAC addresses and locations are not relevant to the network. Technologies such as Cisco’s Discovery Protocol or Layer Link Discovery Protocol has tried to address this void for obvious reasons for like 911. If you have a hard time understanding non physical networks, VOIP could be a learning curve for many people who had to come to deal with it.

Time Division Modulation (TDM)

This standard is called “digital telephony” or “legacy networks” depending on who you talk to. TDM in plain English is a “hard wired” telecom solution. A specific telephone number and other information is set up on specific ports – no matter what. In VOIP, its all virtual, literally the cyberspace of telephony. TDM provides reliability, and five nine reliability. (i.e. the phone system will likely crash for only less than a few minutes every year.)


Wireless is now the defacto standard. More lines are used for cell phones here in the US than wire/landlines. Wireless drives costs down, but reliability is often compromised. Most people under the age of 65 could care less of someone sounding like they are under water.



Service provider focused: This is for customers who are not interested in taking care of their own phone jacks, adding or deleting users or the idea of having hardware in house. In the traditional world this was called Centrex or Central Exchange, in the cyber world its called hosted VOIP, hosted PBX, hosted telephony as its more PC based. The reliability is the responsibility of the provider, and the provider may or may not provide strong reliability. Most major players like the Bells, Comcast, Cablevision and Time Warner of the worlds have great reliability.

On site, “premise based” or Private systems In the Age of the spying scandals of the National Spying (ahem) Security Agency, one may think twice should I really give my communication systems to the cloud or use IP based networking for everything? Private systems come in various forms, you can still find traditional TDM based Private Branch Exchanges or PBX systems, but they come at a high price as many want you to go to VOIP whether you like it or not. If you choose the cyber route, you can set up a VOIP system on its own LAN (if you are that paranoid.) Advantages of private systems give you more control of your communications, and wether or not the NSA can spy on your PBX system is in question, the risk of them spying in a hosted/SP network has less chances. Or what simple logic says.

Application specific: The interesting thing about telecom, is its a puzzle piece. Much like a Lego brick, you can never outgrow it. You start as a toddler with Duplo, graduate to the “System” bricks and if you are nerdy enough graduate to Technics or Mindstorms. But the common theme is they all go together and you never get a lock-in within Lego’s offerings. Telecom for the most part followed Lego’s “system within a system” approach. In the past, you could have Northern Telecom SL1 PBX and use an Octel voice mail mainframe. You could have VOIP trunk on a Cisco network, but terminate the VOIP to the legacy networks using the plain ol telephone ports of an Avaya IP Office. You don’t like Asterisk’s PBX system, but you like the contact center features, you can use a multitude of connectivity and reversed engineering (such as creating dummy extensions or trunks) to link an old Merlin 206 Key system to an Asterisk making a little phone system seem bigger with the contact center functionality.

Telecom is still a relevant technology?!

Oh yeahh… One of the advantages of a telecom logic, is the idea isn’t about say lets build on iOS just for the sake of it, or that the Android can do more (allegedly) there are many different ways communication is traveled, the railroads, and various types of vehicles (old fashioned coal powered trains vs. electrical fast trains.) In the telecom world, you could be lucky and get a fast train to run on an 1800 styled track or get a coal powered train to work on modern monorails. The idea should never become illrelevent, and telecom is an idea, thought process, business practices and not about the “shiny object.” If you focus too much on that “shiny object” it may cost you money and an lost investment. Again, all technologies share this analogy, however its not often practiced as often as would like.