Are "international" SIMS becoming obsolete?

snidely · 24-05-2009, 20:03

HKR - Go to umatoday.com to see a list of carriers that use UMA. I assume, if they wanted, they could prevent you from connecting to an IP outside your home country. Whether any carrier does - I don't know.

Stu and DRN - I look upon you two as the tech gurus here. Can I conclude that some (most?) smart phones, like Iphone and BlackBerry, are (theoretically) able to process voice calls via wifi connection as simply as making regular cell calls? If Blackberrys (Blackberries?) (and Iphones) can be made to do this, that alone would cover a large number of users.

I usually don't carry a computer any more when I travel because of the email features of the BB - which are very inexpensive.

Stu - I assume there is quite an investment in backend costs for UMA and would have to be installed by the underlying carrier in Estonia, Isle of Mann etc. If what I say about installing a Skype type app in a phone is feasible - that would be much easier to implement.

The supposed reason T-M made UMA available in the U.S. was to give users solid mobile service when at home - even if you lived in an area w. littlle or noo cell service. It also was a selling point to get users to ditch their landline since you can make unlimited UMA calls to anywhere in the U.S. for $10/mo.

...mike

DRNewcomb · 24-05-2009, 21:11

Quote:

Originally Posted by snidely

Stu and DRN - I look upon you two as the tech gurus here. Can I conclude that some (most?) smart phones, like Iphone and BlackBerry, are (theoretically) able to process voice calls via wifi connection as simply as making regular cell calls? If Blackberrys (Blackberries?) (and Iphones) can be made to do this, that alone would cover a large number of users.

Well, the phone must have WiFi first. I'm not sure what generalizations can be made. I thought that the E61 would do VPN but it turns out that the VPN is so difficult to configure that it is virtually useless. I don't know to what extent carriers go to cripple the phones they sell, even to the extent of disabling factory capabilities.

Quote:

I usually don't carry a computer any more when I travel because of the email features of the BB - which are very inexpensive.

Stu - I assume there is quite an investment in backend costs for UMA and would have to be installed by the underlying carrier in Estonia, Isle of Mann etc. If what I say about installing a Skype type app in a phone is feasible - that would be much easier to implement.

I'm not so sure it's that difficult. TruPhone does it with an app that logs you onto their SIP service. Once you are logged on they just route your calls via VOIP rather than forwarding to the cell. Now, as I understand it, this is less than UMA. UMA acts more as an alternate air interface. But the idea is that the MVNO can implement a system as an overlay without having to have access to the guts of the cellular switch.

N.B. I thought that Boingo Mobile might be a great way to augment my WiFi access overseas. It is pretty good but you have to take some things they say with a grain of salt. For instance, they list over 10,000 hotspots in Russia.
I started looking for hotspots in various cities. Turns out that something like 9,500 of that 10,000 are the nodes of the Moscow city-wide WiFi system. When you look in other cities, e.g. St. Petersburg, things get pretty slim. St. Petersburg list something like 5 hotels with Boingo Mobile service. Other than Moscow and St. Petersburg I couldn't find any Boingo Mobile hotspots. Bottom line is that I don't think you can really count on WiFi to be there when you need it.

hkr · 26-05-2009, 08:21

Quote:

Originally Posted by DRNewcomb

TruPhone does it with an app that logs you onto their SIP service. Once you are logged on they just route your calls via VOIP rather than forwarding to the cell.

Now that you mention TruPhone... I have long been wondering why they are not forming a nice package of their VoIP service and their international SIM (Sim4Travel).

As for UMA: thanks for the ideas everybody. Well, for me there is indeed no point in buying a US T-Mobile SIM & phone, apart from experimentation.

	(#1)
snidely (Offline) Senior Member Prepaid Expert Posts: 451 Join Date: 09 May 2005 Location: Berkeley, California and Miami Country:	24-05-2009, 20:03 HKR - Go to umatoday.com to see a list of carriers that use UMA. I assume, if they wanted, they could prevent you from connecting to an IP outside your home country. Whether any carrier does - I don't know. Stu and DRN - I look upon you two as the tech gurus here. Can I conclude that some (most?) smart phones, like Iphone and BlackBerry, are (theoretically) able to process voice calls via wifi connection as simply as making regular cell calls? If Blackberrys (Blackberries?) (and Iphones) can be made to do this, that alone would cover a large number of users. I usually don't carry a computer any more when I travel because of the email features of the BB - which are very inexpensive. Stu - I assume there is quite an investment in backend costs for UMA and would have to be installed by the underlying carrier in Estonia, Isle of Mann etc. If what I say about installing a Skype type app in a phone is feasible - that would be much easier to implement. The supposed reason T-M made UMA available in the U.S. was to give users solid mobile service when at home - even if you lived in an area w. littlle or noo cell service. It also was a selling point to get users to ditch their landline since you can make unlimited UMA calls to anywhere in the U.S. for $10/mo. ...mike Make use of T-M's UMA/wifi free calling from any place in the world with access to wifi. I use an LG G6, wife an S7) A/o Oct 20, 2013 no need for intl prepaid as T-Mobile U.S. includes voice roaming at 20¢/min (in and out)., unlimited text (in and out), and unlimited data in 140+ countries. My Plan -[6 lines] U.S. T-Mobile unlimited minutes (incoming and outgoing), unlimited text, fast data on each line. that $145/mo. total! . (In U.S. no surcharge for calling a cell.) If a line exceeds 2G of data in a month, pay $10 more for that line. [That only happens a couple times/year.