All Entries in the "VoIP" Category
G.729 versus G.711
In the last article, we discussed the G.711 codec, which is often used to give you “toll quality” calling. There are situations where you do not have the bandwidth for G.711 calling. Perhaps you have a restricted upstream speeds on your Internet connection or you need more bandwidth for other applications. Another common choice for [...]
Touch Tones and VoIP
A standard analog telephone line is capable of transmitting all kinds of things, ranging from the human voice to music to data–think fax machines and analog models. The Bell System’s focus on audio quality early on in the development of the phone system made this possible. In the 1950s, AT&T was using specific tones–multifrequency tones–on [...]
Telephony And Telegraphy
This short movie from 1946 explains the opportunities you might have had back then as someone who worked in “wire” communications–either telephone or telegraphy: The jobs are indeed fairly similar. They involve wires, communication, routing messages, billing customers, and the like. The main difference is the product: one delivers a voice product, the other involves [...]
Back Before There Was 911
Back before there was a 911 system, the way you got help when you need the police or fire was to dial zero for the operator. Of course, back in the 1960s when the particular movie this still was taken from was shot, human operators were required to complete many types of calls and were [...]
Can You Still Get An Operator?
A seeming “relic” of times gone by is the general-purpose operator, reached by dialing zero. I’m willing to bet that most people under the age of 25 probably have no idea that it was even possible, much less what the operator does. Operators were necessary to complete long distance calls prior to the wide deployment [...]
Video Transmission In 1927
The Bell System was doing a lot more than telephones. That’s part of the reason they experienced anti-trust and breakup orders twice in its history, once in 1956 and again in 1984 when the Bell System was effectively broken up and declared dead. One thing they were doing in the 1920s was experiments with transmitting [...]
Cable? DSL? It’s All Shared, Part 1
Chances are before you got VoIP, you got a broadband connection. And chances are, you had to choose: cable or DSL? Which do you choose? This commercial from Pacific Bell in the 1990s pokes fun at the fact that cable is a shared line versus DSL, which is not, or so they say: In some [...]
Cable? DSL? It’s All Shared, Part 2
In my last post, we were discussing the difference between cable Internet and DSL provided by a local exchange carriers. Cable has a couple of places where the bottleneck can occur: in the neighborhood due to the shared bandwidth, and at the headend where the cable signals are turned over the Internet. DSL is deployed [...]
