Solve : Question about phone networks?

1.	Solve : Question about phone networks?
Answer» Hi, I live on the west coast of the United States. A friend of mine who also LIVES on the west coast recently traveled to New York which is over 3,000 miles away. I called my friend on her cell phone in New York and asked her how she was doing. Here is my question. My friend's cell phone has a California (818) area code. So how was the phone networks able to track her phone to New York, and in a matter of seconds? Thanks! -cinque8All phones have a unique ID, and the minute they are powered they associate with the strongest or next available tower. Even before you place the phone call the system knows where the phone is. This is why cell phone batteries will drain faster when there is no signal strength to a tower or last for days when in a location where the signal strength is strong. As long as the phone is powered it ESTABLISHES connection to towers. This also allows for tracking of people for forensic purposes to see where people were based on triangulation and you can log the wereabouts of where a person has been based on the logs that the phone company keeps with the towers which is also part of the homeland security system now.Thanks for the reply Egghead. I assume that if her phone was not turned on I would have got her voice mail, or it would have continued to ring. But since I placed the call in California, did the network check every tower in America (or the world) until it found this particular phone? Thanks!If she just once had her phone one time away from home, a record is kept of where she was while the phone was in idle mode. And even if she did not even made or answered a call. The database is updated almost instantly about once every twenty minutes. If you want to try a little experiment, place a cell phone next to some device that is sensitive to a EMF. Example might be the speakers of your desktop PC. UNPLUG the speaker amplifier from the PC, turn up the volume. Next put the input near the cell phone, but not touching it. Wait a few moments. Soon you will hear the cell phone reveal its presence. It is a very quack burst of digital code. Less that two seconds. Aurelio Interference from Mobile Phone.Thanks Geek! Quote from: DaveLembke on November 15, 2013, 04:20:21 PM All phones have a unique ID, and the minute they are powered they associate with the strongest or next available tower. Even before you place the phone call the system knows where the phone is. A cell (mobile) phone network is really a computer network. Towers (we call them "masts" in the UK) are nodes on that network. When a mast associates with a phone the unique ID of that phone is passed to the central computers of the network where it is stored (and logged) and when another phone user dials the number of that phone there is no need to search for it mast by mast. If the caller is on a different network the request is passed to the appropriate host network. I never knew that US cell providers assign area codes. In the UK, mobile numbers are usually given in the form 0 (which you dial before all nonlocal numbers) then a 7 (which means it is a mobile) then 3 digits which identify the provider then a 6 digit phone number. E.g. 07623 123456. Outside the UK you would dial the full international form of the number which is written without the leading zero with the country code in parentheses, preceded by a plus sign e.g. (+44) 7623 123456. Mobile phone companies in different countries have mutual AGREEMENTS so if you took a UK mobile to Spain and switched it on you would connect to whatever Spanish network your UK provider has an agreement with, but voice, SMS and data use incurs a sometimes heavy "roaming" charge. In the UK, we don't pay for incoming voice or SMS but when roaming these are billed. Within the European Union there is a maximum data roaming charge of 0.45 euros (about 60 US cents) per megabyte, reducing to 0.20 euros in July 2014, but outside the EU you pay whatever your provider charges. There have been widely publicised huge bills. Now that many younger (and not so young) people seem to live their whole lives on social networks this can be expensive. One UK woman went to Turkey in 2011 and used data roaming for 4 days. She forgot to switch off app updates and used Google Maps and used Facebook a lot, uploading lots of photos (probably shaky ones of the insides of bars). She got charged 42,200 pounds (67,988 dollars). This was reduced to 700 pounds (1,122 dollars) after she disputed the bill, and bills (that have to be paid) of 1 to 5 thousand dollars are not unheard of. Wkipedia to the rescue! "In many countries, mobile phones are assigned dedicated mobile phone codes within the country's telephone numbering plan. Some countries that do not use area codes (e.g. Singapore) allocate specific number ranges to mobile phones that are easily distinguishable from landlines. One notable exception to this type of assignment is the countries within the North American Numbering Plan (the United States and its territories, Canada, and much of the Caribbean), in which mobile phones are assigned subscriber numbers within geographic area codes, and are not easily distinguishable from landlines." I never knew that. Salmon, thanks for the post. In the previous posts that I have made on this forum, I have never received so much information! You mentioned that mobile numbers in the UK are preceded by a zero, in the US numbers outside of your area code are best preceded by a "1", for example 1 (818) 444-5555, but the call will still go through without the "1". Quote from: cinque8 on November 16, 2013, 02:22:02 AM Salmon, thanks for the post. In the previous posts that I have made on this forum, I have never received so much information! You mentioned that mobile numbers in the UK are preceded by a zero, in the US numbers outside of your area code are best preceded by a "1", for example 1 (818) 444-5555, but the call will still go through without the "1". In the UK, each city or area has a "dialling code", for example the city of Bristol where I live has the code 0117. Brackets around this are optional. After that there is a 3 digit number which is the district "exchange", and finally a 4 digit number for my phone. Suppose my full number is (0117) 950 1234. From another landline within the 0117 code area you only have to dial 950 1234 to call me. You could use the 0117 and it would still work the same. If you lived outside the area you would have to use the full number. You would also have to use the full number from a mobile phone. Because of this people nowadays tend to give their full landline number, even to people who they know live in the area. London is so big the phone numbers have 8 digits now. Very interesting reading. Quote: ...Because of the popularity of fax machines and cell phones, far more telephone numbers were needed to handle the demand, and the decision was taken to add more area codes rather than increase the number length. Since 1995, there have been over 380 new area codes added in the North American Numbering Plan area. Some created area code splits (where an existing area code was split up into two or more new area codes). This cost businesses and others a lot of money reprinting stationery, business cards, etc. These were often greatly contested as to which area could keep the old area code (usually the largest city kept the old code). For instance, 305 was split in 1995. It used to serve both the Miami and Fort Lauderdale area. Dade County (at the time, now called Miami-Dade) kept 305 and Broward County (the Fort Lauderdale area) had to change to 954. Because splits were challenged so strongly, overlays were created when possible. An overlay was a new area code that covered the same geographical area as an existing code. This enabled people to keep their old area code, while new phone numbers would get the new area code. There have been over 75 overlays introduced since 1995.[3] ... end quote http://en.wikipedia.org/wiki/Telephone_numbering_planDepending on where you live in the US, you may have to "dial" 10 digits or only 7 digits from a land-based phone to any other phone in the same area. Even some numbers within the same area code are long distance. From a cell phone, 10 digits is always required, even for local calls. VOIP phones are also 10 digit dialing. Land based phones, i.e. land lines, use virtually the same scheme as it was 150 years ago. It was derived from the telegraph & used the same lines. The infrastructure & technology has changed, but a 100 year old telephone will still function on the land line, pulse dialing still works. The Central Office is still powered by batteries. Telephone networks & the internet share infrastructures wherever they can, primarily fiber optic lines. Cell phones are not 100% "in the air", i.e. they don't jump from cell tower to cell tower for 3000 miles. You can make phone calls to Hawaii; there's no towers in the middle of the Pacific Ocean. They have internet, too. Think, "subsea fiberoptic cable", now. TransAtlantic Cable back about 150 years ago for the telegraph. Does anyone even know what a telegraph was, anymore? The were in many of the old Westerns & figured prominently in the Civil War. President Lincoln ran the War by use of the telegraph. Now it's done over the Internet. That's why DARPA funded the development from the beginning. Quote from: Computer_Commando on November 16, 2013, 03:11:06 PM Does anyone even know what a telegraph was, anymore? My friend's son recently did a school project on the telegraph. The history and science. They even rigged up a line between two rooms and and using batteries, Morse keys and buzzers communicated (slowly) using Morse code. Quote from: Salmon Trout on November 16, 2013, 03:16:02 PM My friend's son recently did a school project on the telegraph. The history and science. They even rigged up a line between two rooms and and using batteries, Morse keys and buzzers communicated (slowly) using Morse code. I was very interested by the work he did, and the quality of the teaching. They even learned about one of my heroes, William Henry Preece, who signalled across the Atlantic Telegraph Cable using a battery made by sticking two wires into a lemon. He did this to confound critics who thought that huge batteries would be necessary. My young friend was deeply impressed that all this happened 150 years ago. School here is not so good. I remember taking World History & American History, which focused on dates which events took place. Pretty boring stuff. The best teachers were always the math & science, the others couldn't even make their own field of expertise interesting. They probably found it boring, too. The University was even worse. Professors ignored undergraduates, teaching assistants who can't communicate, an administration who could care less. Unconsciously, the were preparing you for real life. 1st quote on the list here: http://en.wikiquote.org/wiki/H._L._Mencken Never knew that until now. It's pretty cool, how a breakthrough by one person changes everything forever, whether tech or other. In the States, we don't appreciate, the breakthroughs you made across the Pond. Everyone thinks it was invented here. Just a few: steam power, railroads, radio, radar, aircraft, jet engines Quote from: Computer_Commando on November 17, 2013, 10:04:16 AM School here is not so good. They are very variable in quality here. One or two dedicated teachers can really lift a school.

Answer»

Hi,

I live on the west coast of the United States. A friend of mine who also LIVES on the west coast recently traveled to New York which is over 3,000 miles away. I called my friend on her cell phone in New York and asked her how she was doing. Here is my question. My friend's cell phone has a California (818) area code. So how was the phone networks able to track her phone to New York, and in a matter of seconds?

Thanks!

-cinque8All phones have a unique ID, and the minute they are powered they associate with the strongest or next available tower. Even before you place the phone call the system knows where the phone is. This is why cell phone batteries will drain faster when there is no signal strength to a tower or last for days when in a location where the signal strength is strong. As long as the phone is powered it ESTABLISHES connection to towers. This also allows for tracking of people for forensic purposes to see where people were based on triangulation and you can log the wereabouts of where a person has been based on the logs that the phone company keeps with the towers which is also part of the homeland security system now.Thanks for the reply Egghead.

I assume that if her phone was not turned on I would have got her voice mail, or it would have continued to ring. But since I placed the call in California, did the network check every tower in America (or the world) until it found this particular phone?

Thanks!If she just once had her phone one time away from home, a record is kept of where she was while the phone was in idle mode. And even if she did not even made or answered a call. The database is updated almost instantly about once every twenty minutes.

If you want to try a little experiment, place a cell phone next to some device that is sensitive to a EMF. Example might be the speakers of your desktop PC. UNPLUG the speaker amplifier from the PC, turn up the volume. Next put the input near the cell phone, but not touching it. Wait a few moments. Soon you will hear the cell phone reveal its presence. It is a very quack burst of digital code. Less that two seconds.
Aurelio Interference from Mobile Phone.Thanks Geek! Quote from: DaveLembke on November 15, 2013, 04:20:21 PM

All phones have a unique ID, and the minute they are powered they associate with the strongest or next available tower. Even before you place the phone call the system knows where the phone is.

A cell (mobile) phone network is really a computer network. Towers (we call them "masts" in the UK) are nodes on that network. When a mast associates with a phone the unique ID of that phone is passed to the central computers of the network where it is stored (and logged) and when another phone user dials the number of that phone there is no need to search for it mast by mast. If the caller is on a different network the request is passed to the appropriate host network.

I never knew that US cell providers assign area codes*. In the UK, mobile numbers are usually given in the form 0 (which you dial before all nonlocal numbers) then a 7 (which means it is a mobile) then 3 digits which identify the provider then a 6 digit phone number. E.g. 07623 123456. Outside the UK you would dial the full international form of the number which is written without the leading zero with the country code in parentheses, preceded by a plus sign e.g. (+44) 7623 123456. Mobile phone companies in different countries have mutual AGREEMENTS so if you took a UK mobile to Spain and switched it on you would connect to whatever Spanish network your UK provider has an agreement with, but voice, SMS and data use incurs a sometimes heavy "roaming" charge. In the UK, we don't pay for incoming voice or SMS but when roaming these are billed. Within the European Union there is a maximum data roaming charge of 0.45 euros (about 60 US cents) per megabyte, reducing to 0.20 euros in July 2014, but outside the EU you pay whatever your provider charges. There have been widely publicised huge bills. Now that many younger (and not so young) people seem to live their whole lives on social networks this can be expensive. One UK woman went to Turkey in 2011 and used data roaming for 4 days. She forgot to switch off app updates and used Google Maps and used Facebook a lot, uploading lots of photos (probably shaky ones of the insides of bars). She got charged 42,200 pounds (67,988 dollars). This was reduced to 700 pounds (1,122 dollars) after she disputed the bill, and bills (that have to be paid) of 1 to 5 thousand dollars are not unheard of.

* Wkipedia to the rescue! "In many countries, mobile phones are assigned dedicated mobile phone codes within the country's telephone numbering plan. Some countries that do not use area codes (e.g. Singapore) allocate specific number ranges to mobile phones that are easily distinguishable from landlines. One notable exception to this type of assignment is the countries within the North American Numbering Plan (the United States and its territories, Canada, and much of the Caribbean), in which mobile phones are assigned subscriber numbers within geographic area codes, and are not easily distinguishable from landlines." I never knew that.
Salmon,

thanks for the post. In the previous posts that I have made on this forum, I have never received so much information! You mentioned that mobile numbers in the UK are preceded by a zero, in the US numbers outside of your area code are best preceded by a "1", for example 1 (818) 444-5555, but the call will still go through without the "1". Quote from: cinque8 on November 16, 2013, 02:22:02 AM

Salmon,

thanks for the post. In the previous posts that I have made on this forum, I have never received so much information! You mentioned that mobile numbers in the UK are preceded by a zero, in the US numbers outside of your area code are best preceded by a "1", for example 1 (818) 444-5555, but the call will still go through without the "1".

In the UK, each city or area has a "dialling code", for example the city of Bristol where I live has the code 0117. Brackets around this are optional. After that there is a 3 digit number which is the district "exchange", and finally a 4 digit number for my phone. Suppose my full number is (0117) 950 1234. From another landline within the 0117 code area you only have to dial 950 1234 to call me. You could use the 0117 and it would still work the same. If you lived outside the area you would have to use the full number. You would also have to use the full number from a mobile phone. Because of this people nowadays tend to give their full landline number, even to people who they know live in the area. London is so big the phone numbers have 8 digits now.
Very interesting reading.
Quote:
...Because of the popularity of fax machines and cell phones, far more telephone numbers were needed to handle the demand, and the decision was taken to add more area codes rather than increase the number length. Since 1995, there have been over 380 new area codes added in the North American Numbering Plan area. Some created area code splits (where an existing area code was split up into two or more new area codes). This cost businesses and others a lot of money reprinting stationery, business cards, etc. These were often greatly contested as to which area could keep the old area code (usually the largest city kept the old code). For instance, 305 was split in 1995. It used to serve both the Miami and Fort Lauderdale area. Dade County (at the time, now called Miami-Dade) kept 305 and Broward County (the Fort Lauderdale area) had to change to 954. Because splits were challenged so strongly, overlays were created when possible. An overlay was a new area code that covered the same geographical area as an existing code. This enabled people to keep their old area code, while new phone numbers would get the new area code. There have been over 75 overlays introduced since 1995.[3] ...
end quote
http://en.wikipedia.org/wiki/Telephone_numbering_planDepending on where you live in the US, you may have to "dial" 10 digits or only 7 digits from a land-based phone to any other phone in the same area. Even some numbers within the same area code are long distance. From a cell phone, 10 digits is always required, even for local calls. VOIP phones are also 10 digit dialing.

Land based phones, i.e. land lines, use virtually the same scheme as it was 150 years ago. It was derived from the telegraph & used the same lines. The infrastructure & technology has changed, but a 100 year old telephone will still function on the land line, pulse dialing still works. The Central Office is still powered by batteries.

Telephone networks & the internet share infrastructures wherever they can, primarily fiber optic lines. Cell phones are not 100% "in the air", i.e. they don't jump from cell tower to cell tower for 3000 miles. You can make phone calls to Hawaii; there's no towers in the middle of the Pacific Ocean. They have internet, too. Think, "subsea fiberoptic cable", now. TransAtlantic Cable back about 150 years ago for the telegraph.

Does anyone even know what a telegraph was, anymore? The were in many of the old Westerns & figured prominently in the Civil War. President Lincoln ran the War by use of the telegraph. Now it's done over the Internet. That's why DARPA funded the development from the beginning.

Quote from: Computer_Commando on November 16, 2013, 03:11:06 PM

Does anyone even know what a telegraph was, anymore?

My friend's son recently did a school project on the telegraph. The history and science. They even rigged up a line between two rooms and and using batteries, Morse keys and buzzers communicated (slowly) using Morse code.

Quote from: Salmon Trout on November 16, 2013, 03:16:02 PM

My friend's son recently did a school project on the telegraph. The history and science. They even rigged up a line between two rooms and and using batteries, Morse keys and buzzers communicated (slowly) using Morse code.

I was very interested by the work he did, and the quality of the teaching. They even learned about one of my heroes, William Henry Preece, who signalled across the Atlantic Telegraph Cable using a battery made by sticking two wires into a lemon. He did this to confound critics who thought that huge batteries would be necessary. My young friend was deeply impressed that all this happened 150 years ago.
School here is not so good. I remember taking World History & American History, which focused on dates which events took place. Pretty boring stuff. The best teachers were always the math & science, the others couldn't even make their own field of expertise interesting. They probably found it boring, too.

The University was even worse. Professors ignored undergraduates, teaching assistants who can't communicate, an administration who could care less. Unconsciously, the were preparing you for real life.

1st quote on the list here: http://en.wikiquote.org/wiki/H._L._Mencken
Never knew that until now.

It's pretty cool, how a breakthrough by one person changes everything forever, whether tech or other.

In the States, we don't appreciate, the breakthroughs you made across the Pond. Everyone thinks it was invented here.
Just a few: steam power, railroads, radio, radar, aircraft, jet engines

Quote from: Computer_Commando on November 17, 2013, 10:04:16 AM

School here is not so good.

They are very variable in quality here. One or two dedicated teachers can really lift a school.

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