We are all accustomed to using “ping” as a way to test Internet connectivity and to measure the latency of an Internet connection. This post talks about a similar function for telephones, a function that can be very helpful in testing the configuration of a VOIP (voice over IP) telephone. Continue reading
Let’s suppose you have made a plan to migrate your office telephone system from analog phone lines to VOIP trunks. Maybe you are doing this to reduce your monthly telephone bill to 85¢ as I blogged recently. But regardless of why you are migrating, clearly you will want to carry out the migration in a way that minimizes the risk of disruption of incoming or outgoing telephone service. In this article I describe a migration path that worked well for our firm, and along the way I explain a little bit more about SIP trunking and how it works. Continue reading
In a previous blog post I discussed two companies that you probably never heard of that make telephone calls possible — Neustar and iconectiv. These companies administer the NPAC database, which is a database that gets consulted each and every time that any one dials a telephone call to a US (non-toll-free) telephone number. A million times per day, a telephone call gets placed to a US telephone number, and a million times a day, a lookup happens to this NPAC database, without which the phone call would not be able to reach its destination. And if you are like me, you never heard of either company.
In this blog post I will discuss another group of companies that you probably also never heard of, that are responsible for a super important part of the way that telephone calls take place. This category of companies does not, so far as I know, have a name. I will call them “VOIP wholesalers”. Some of these companies are called Onvoy, Bandwidth, Paetec, Peerless, Level 3 Communications, XO Communications, and Aerialink. I had heard of Level 3 before, but I only knew them as an Internet company. The other three companies I had never heard of at all until very recently. What do VOIP wholesalers do, and why should you care? Continue reading
Whenever you dial a telephone number that is located in the US, somehow your telephone company needs to be able to figure out which telephone company will complete the call. So for example suppose your cellular carrier is AT&T and you pick up your cell phone and dial a phone number. One of the first things that AT&T must do is somehow to figure out which telephone company is responsible for that phone number. Maybe that phone number is handled by Verizon. If so, then somehow AT&T needs to know to send your call to Verizon which will complete the telephone call.
How does your telephone company come to learn which telephone company is responsible for that phone number? Keep in mind that the person you are calling might “port” their cell phone number tomorrow from Verizon to T-Mobile. If so, then if you were to dial the same telephone number the day after tomorrow, your telephone company would need to know to send your call to T-Mobile instead of sending it to Verizon.
How does this work? And how does this relate to “number portability”? Continue reading
These days, the way to go if you are picking a new telephone system is a system based upon Asterisk, which is open-source software providing a PBX for SIP telephones service. If you have a legacy telephone system, it may make sense to retire the legacy system and to move to a SIP-based system. I will explain. Continue reading
Recently I blogged with a recommendation that readers migrate their $40 or $55 per month landlines to VOIP lines that cost as little as 85¢ per month. In response, alert reader and Portuguese and European patent attorney Luís Ferreira asked:
What about security? SIP communications are not normally encrypted?
His questions are good questions. Here are a few partial answers.
We reduced our firm’s $160 per month phone bill for four telephone lines to 85¢ per month. Continue reading
If you are going to use VOIP (which probably you should do, since it is the wave of the future), you might need one or more ATAs (analog telephone adapters). If so, this article offers my recommendation of which one to pick.
The landscape for VPN routers has changed over the years. As of a few years ago, sophisticated VPN routers with IPSEC were ethernet-only. Continue reading
Okay folks here is a chance to win a free digital multimeter.
What prompts this is that I keep hearing a particular music-on-hold (MOH) song on lots of different tech support and customer service systems. So I figure this song is probably one of the standard royalty-free MOH songs that comes with the Asterisk phone system or something. You can hear the song here.
To win the prize, post a comment with a link to the web page where this particular MOH song can be downloaded.