hand-off in cellular systems?
453941
a hand off is when your in the middle of a cell phone call and switch carrier coverage. if you have a sprint phone and talking on sprint and leave their area, then instead of losing your call you are handed-off to another company with antennas in the area.\n\nif your talking hands-free phones sorry
1161314
If u have mobile call ur home,if stuckup call SOS no. from ur mobile. In Hyderabad in India they have well established helpline.Every country has helpline.
1003961
I don't believe they have the right to demand that you not carry your cell phone.  Unless it impedes the quality or safety of your work.  Or are just worried about inneffeciency in the temptation of using your cell phone during work.  I wouldn't see that happening though.  Your employer might just be uptight.
1124247
Depends on your phone company
566437
I work for a large company and fly on the company jet from time to time.  The crew allow us to use our cell phones, stating that they can't interfere with the systems on our Beech 400 bizjets.  Fair enough.  But...\n\nUp to about 4000 feet AGL after takeoff there is a useable signal.  Beyond that, it all goes dead.  As quickly as those babies climb, the phones go dead about a minute or so after takeoff.  Even holding a phone next to a window to negate the effects of the metal fuselage makes no difference.\n\nOut of curiosity, I watched the phone display rather intently over a couple of flights in various parts of the country to see if I ever got a signal.  Cruising above 20,000 feet -- nada.  Nothing.  Not a single bar.  A couple times I did see a very brief flicker below 10,000 feet as we came down for landing and then got generally good signals somewhere around 4,000 feet and below.\n\nWhile this minimal testing on my part is hardly conclusive and does not include the area around the flight path of Flight 93, I would have to say that any depiciton of people using personal cell phones is probably ficticious, based solely on my limited experience.  \n\nThat said, my service is GSM.  I have not tested this with a CDMA/TDMA or iDen phone.  Signal propogation of those technologies could well be different.  \n\nThere could also have been unsual climactic conditions on that fateful day that allowed cellular communications to function for those folks.  I have no evidence one way or another on that possibility.\n\nOf course, many airliners have the commercial Airphone systems installed.  Those would most likely have worked reliably.  I just hope the company that operates it did not charge those folks for their calls on that day.
557779
you can take a cellular phone, it's work very well ;)
20671
Verizon Wireless offers free mobile to mobile in network.
653186
Because picking up the phone and saying GOODBYE would be out of the question.
999484
No, my job does not, but I totally know what you mean. Cell phones are great for most people - but have you ever been in an airport and watched those poor businessmen? They are like making deals while standing in line! Travel was probably their one escape from work during the pre-cell era. Now that is gone. How sad.
776506
In short, no.\n\nWhen a person dials 911 on a traditional phone, computers at the phone company route the call the the proper center based upon the number you are calling from if it is a landline.  \n\nIf you dial 911 using a cell phone the call is often routed by the phoen company's computers based upon the location of the cell tower, which might not be the right call center for the jurisdiction of the incident.  Your call must then be transferred to the correct center for processing.\n\nIn either case, the routing of the call is happening at the phone company's computers.\n\nBut with VOIP (Voice Over Internet Protocol) phone calls, the call is routed differently.  If you are calling another VOIP user on the same network  (one skype user calls another) the call is never handled by the phone company (unless it is also the ISP).  If you use a VOIP account to call a landline phone, the call does not enter the phoen company's switching system until it is near the recipient of the call, possibly in another state or country!  \n\nThe limitations of VOIP calls means that it is difficult to determine where the call originates from.  That information is needed to determine which call center should receive the call for a 911 call.\n\nThe only way to use a VOIP account to dial emergency services is to learn an administrative phone number for the emergecny communications center in your area.  Still this could be a problem based upon how calls are sometimes transferred for further processing prior to dispatch.\n\n911 centers are continuing to look at emerging technologies.  In the future it may be possible cal 911 by SMS text message, instant message, or VOIP.  For now, a landline phone or cell phone is still the way to go.
100966
Land line is necessary. If you have a land line then you can use cellular phone's free minutes by using a dock station. This device used to be sold couple years ago and haven't seen somebody using it.
618123
I'm not sure, but I do wish that when they had multiple lines you could just call one number and it would be taken by whichever line is open for your contestant.  It's easier to hit redial, but then you wonder if the other numbers are free when the one you're dialing is busy.
548473
If its my number, theres no point, i have another sim i can use whilst i'm here
1038038
call ur cell provider
1029353
As others have answered, it's because the signal is passed from one "cell", or transmitting tower to another as you move.\n\nUp until the mid or late 80's, there were still mobile phones which were not cell phones.  These were basically just specialized radios, and had limited range.  They were expensive and limited to people like doctors and the wealthy.  I'm not sure when they finally phased them out, or even if they are still available somewhere, but as cell phones became more & more common, and the coverage got better, there was just no need for the old style mobile phones, and the two terms became synonymous.
17191
I can see a day when broadband companies simply decide to cut off the access to the Vonage-type providers by port blocking or other means---And court battles about it.  Even if that doesn't happen, I think it would take a long long time for anything to impact the old Ma-Bell phone companies signifigantly.  Cell phones?  I've never seen an internet phone product that would compete with wireless phones.
599514
Well it would really depend on what hour it is now. But I would probably leave but place a forwarding to my own cellphone so that I can answer any calls made to the office :P