re. Copper outside plant facilities.
True we're going to be using copper lines for our local telco provided voice and internet services (DSL, ADSL) for the next 10 yrs or so but it's a dying science for providing POTS service to every endpoint.
Now what the local telco's are doing is setting "pedestals" at strategic localtions and feeding subdivisions and business clusters POTS/DSL service from them. The pedestals are basically small digital switching centers (SLIC's) that feed back to the CO either via fibre (newer) or T1/T3 (legacy) trunking. Any lineman you see running new transport facilities on the poles is either installing fibre or coax as main trunks and copper lines from the pedestals to the endpoint.
Most of you have probably heard of DSLAMs inregards to DSL, well these pedestals house the DSLAMs.
The day where fibre is run upto the endpoint is approaching very quickly and is being done in certain locales now.
re. VOIP. As stated VOIP has been used for inter/intra CO transport for yrs. VOIP when "dedicated" for voice service is an excellent mode of transporting the spoken word.
The key to "toll quality" VOIP is guaranteed bandwidth and is measured by the transports QOS (quality of service). In dedicated networks QOS isn't as necessary as all the transmissions are voice, with alittle data thrown in (fax, dialup modem). Mixed dedicated networks such as MPLS have routers and switches w/QOS and toll quality voice isn't a problem there either. (unless the enduser doesn't purchase enough CIR (Committed Information Rate, and in this case both the voice and data will suffer, but thats another story).
A "good" toll quality conversation requires approx 32K which is achieved via voice compression. (V.729a). As long as the conversation has atleast 32K of IP broadband bandwidth available between the two endpoints, the voice quality will be just about as clear as an old POTS line point to point connection and/or dedicated T1 channel 64k connection. The problem w/using VOIP over the internet is the bandwidth cannot be guaranteed so the conversation is subject to the varying demands and conjestion present between the endpoints. Most times it's not an issue, especially in residential usage but it can be a major problem when trying to conduct business.
Depending upon the type of broadband you have, cable, DSL/ADSL there are "hub's" located at various points that combine many endpoints together and then switch them onto a main transport (fibre, T1/T3, multiple coax) to a main switching center then off to the world. Theres many points where conjestion can and does occur hense the reason why your internet gets slower at times or your VOIP conversation has static and broken speech.
Basically VOIP is all about bandwidth and the proper routers/data switches to provide QOS. If'n you've got it, its great, if'n you don't, well, it ain't so great
re. CO dialling plans. The FCC mandated that the little Ma & Pa CO's that are still out there be able to access the latest and greatest technology in voice/data switching that the larger more prosperous population centers with more sophisticated switching centers have and the FCC likes uniformality. Highly extensive and complicated dialing plans require the memory and processing power to provide & translate and some of the smaller Central Offices that are still providing reliable but dated voice/data services just don't have it.
Back in the day, a leading "1" signified a toll call and the 2nd digit after that (1 or 0)signified whether the call was a toll call within the present area code or a toll call to another area code. This remained unchanged for decades until the demand for tel numbers exceeded the 2nd digit indentifier requirement. Now adays a local toll free call can contain a 0 or 1 as the 2nd digit but the leading "1" is still used by landline CO's as the identifier between a toll and toll free call per FCC decree.
Some CO's have the memory and processing power to translate a call regardless if a leading "1" is dialed but many can't hense the requirement. It can get very aggravating when you have a calling plan such as a "circle 40" where any call to an endpoint that is within 40 miles of you is toll free but the CO is limited in it's processing ability to break it out so you have to remember to dial certain numbers with a leading "1" and others with the same area code without the leading "1". Just like the OP stated in his 1st post
Anyways, it's a limitation of the hardware thats used by the local telco thats providing your service as to why you have to dial certain digits
Clear as mud?
