Re: Seamless switching from gprs to wifi calling
I'll have to come back on this... I've read several stories about t-mobile's [EMAIL PROTECTED] service lately, and it seems like t-mobile made it possible to let it switch between UMA and airwaves. I intentionally don't call it seamless, because it isn't. (yet?) Several reports say it takes a second or two to switch between WiFi and GSM airwaves -- Luit On 6/10/07, Luit van Drongelen [EMAIL PROTECTED] wrote: Hi, As I said, to do the T-Mobile thing, you'd need a GSM/UMA backbone that's capable of routing calls through both. Though I don't think it's easy to reroute (hand over) a call from one of the protocols to the other. It requires timing, which requires computing power, which requires a mighty strong backbone for all the people using the service. So my guess is that T-Mobile's Hotspot services only lets you use one of the two protocols. As long as you're near a hotspot, you're logged in to the UMA backbone, and your phone number is assigned to that hotspot service. If you're not logged in, incoming and outgoing calls are routed through GSM normally. And there's the problem for doing it yourself. You can't really decide for yourself where the calls for your number are routed to. The service provider decides, and without a T-Mobile Hotspot @ home-like service backbone, you can't do this. You can either call through WiFi using SIP, but it'll use your SIP number, not your GSM number. And vice-versa. It's all up to the service provider to enable goodness like this... :( -- Luit On 6/8/07, mathew davis [EMAIL PROTECTED] wrote: Thanks for all the input. Sounds very interesting. I didn't realize that UMA isn't VoIP. I don't want to use t-mobiles system. I was thinking of how I could do it without using their system, but the same idea. Sounds like I have got a lot fo reading ahead of me and that this problem is bigger than I thought it would be. Just to make sure I got every thing right GPRS is to slow. Inorder to get something like this to work you need the following: Client software capable of handling 2 streams sip and gsm. It also has to know when to hand over from one to the other. You also need a server that can handle the 2 streams and know when to throw away the extra data. Does that sound right? Just want to make sure I understand what you guys wrote. That IMS thing sounds interesting I will have to do some research on that. Thanks for the info. On 6/8/07, Luit van Drongelen [EMAIL PROTECTED] wrote: To get back to what Mathew asked: I don't think a T-Mobile [EMAIL PROTECTED] is switching calls back and forth as you get in reach of a hotspot, and walk away from it. Secondly: this only works with T-Mobile! (for now) T-Mobile has probably set up a [EMAIL PROTECTED] call server near their GSM traffic backbone, on which your phone logs in, and through which your GSM traffic goes (with that UMA protocol) while you're logged in (in reach of a public (T-mobile) hotspot). Calls that already take place can't be re-routed I guess... Anyway, what I'm trying to say is that firstly: you need T-Mobile as your operator. Secondly: you need that T-Mobile HotSpot @home plan. Thirdly: you need a phone that's capable of routing your GSM traffic through UMA, to the T-Mobile UMA server/backbone/whatever they call it. As for the Neo1973 and OpenMoko: The phone can most likely do it, because the software just needs to know how to do it. BUT, I don't think T-Mobile will tell you how to log in. T-Mobile makes the phone software themselves for a reason. If they show you how to make a phone log in, you can make a program that logs your computer in too. So a FOSS solution for this probably won't come easily. -- Luit PS: sorry for the double post Johnson, it bounced because I mailed from the wrong account On 6/8/07, Al Johnson [EMAIL PROTECTED] wrote: Check the archives for a full discussion of this. In short GPRS is unsuitable for VoIP because of the high latencies, often in seconds. The GSM data mode is more suitable even though it's only 9600. It should be possible to have Asterisk route calls to the right VoIP endpoint, or to a GSM voice call if it can place calls to the PSTN. The trick comes in knowing when to hand over, and having a unified client that'll get Asterisk to do it. On Friday 08 June 2007 06:21, kenneth marken wrote: mathew davis wrote: Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would
Re: Seamless switching from gprs to wifi calling
Hi, As I said, to do the T-Mobile thing, you'd need a GSM/UMA backbone that's capable of routing calls through both. Though I don't think it's easy to reroute (hand over) a call from one of the protocols to the other. It requires timing, which requires computing power, which requires a mighty strong backbone for all the people using the service. So my guess is that T-Mobile's Hotspot services only lets you use one of the two protocols. As long as you're near a hotspot, you're logged in to the UMA backbone, and your phone number is assigned to that hotspot service. If you're not logged in, incoming and outgoing calls are routed through GSM normally. And there's the problem for doing it yourself. You can't really decide for yourself where the calls for your number are routed to. The service provider decides, and without a T-Mobile Hotspot @ home-like service backbone, you can't do this. You can either call through WiFi using SIP, but it'll use your SIP number, not your GSM number. And vice-versa. It's all up to the service provider to enable goodness like this... :( -- Luit On 6/8/07, mathew davis [EMAIL PROTECTED] wrote: Thanks for all the input. Sounds very interesting. I didn't realize that UMA isn't VoIP. I don't want to use t-mobiles system. I was thinking of how I could do it without using their system, but the same idea. Sounds like I have got a lot fo reading ahead of me and that this problem is bigger than I thought it would be. Just to make sure I got every thing right GPRS is to slow. Inorder to get something like this to work you need the following: Client software capable of handling 2 streams sip and gsm. It also has to know when to hand over from one to the other. You also need a server that can handle the 2 streams and know when to throw away the extra data. Does that sound right? Just want to make sure I understand what you guys wrote. That IMS thing sounds interesting I will have to do some research on that. Thanks for the info. On 6/8/07, Luit van Drongelen [EMAIL PROTECTED] wrote: To get back to what Mathew asked: I don't think a T-Mobile [EMAIL PROTECTED] is switching calls back and forth as you get in reach of a hotspot, and walk away from it. Secondly: this only works with T-Mobile! (for now) T-Mobile has probably set up a [EMAIL PROTECTED] call server near their GSM traffic backbone, on which your phone logs in, and through which your GSM traffic goes (with that UMA protocol) while you're logged in (in reach of a public (T-mobile) hotspot). Calls that already take place can't be re-routed I guess... Anyway, what I'm trying to say is that firstly: you need T-Mobile as your operator. Secondly: you need that T-Mobile HotSpot @home plan. Thirdly: you need a phone that's capable of routing your GSM traffic through UMA, to the T-Mobile UMA server/backbone/whatever they call it. As for the Neo1973 and OpenMoko: The phone can most likely do it, because the software just needs to know how to do it. BUT, I don't think T-Mobile will tell you how to log in. T-Mobile makes the phone software themselves for a reason. If they show you how to make a phone log in, you can make a program that logs your computer in too. So a FOSS solution for this probably won't come easily. -- Luit PS: sorry for the double post Johnson, it bounced because I mailed from the wrong account On 6/8/07, Al Johnson [EMAIL PROTECTED] wrote: Check the archives for a full discussion of this. In short GPRS is unsuitable for VoIP because of the high latencies, often in seconds. The GSM data mode is more suitable even though it's only 9600. It should be possible to have Asterisk route calls to the right VoIP endpoint, or to a GSM voice call if it can place calls to the PSTN. The trick comes in knowing when to hand over, and having a unified client that'll get Asterisk to do it. On Friday 08 June 2007 06:21, kenneth marken wrote: mathew davis wrote: Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would like it to be a little different, I don't want to use T-Mobile's service I would like to use my Wi-Fi connection to my VoIP of choice. I know this has been talked about before with some options including an Astrex box forwarding the call to your cellphone until your in range then switching to Wi-Fi but that was not a very seamless transistion from my understanding. So I guess my question is could we impliment a UMA type of technology for the neo that
Re: Seamless switching from gprs to wifi calling
On Thursday 07 June 2007 23:05:44 mathew davis wrote: Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would like it to be a little different, I don't want to use T-Mobile's service I would like to use my Wi-Fi connection to my VoIP of choice. I know this has been talked about before with some options including an Astrex box forwarding the call to your cellphone until your in range then switching to Wi-Fi but that was not a very seamless transistion from my understanding. So I guess my question is could we impliment a UMA type of technology for the neo that is customizable to use our VoIP provider? Or since that particular part is locked we wouldn't have access to that part? Be careful. UMA is not VoIP as is usually meant. UMA is more like GSM over IP. Basically GSM signalling is carried by an IP network. So from the GSM network point of view, it's relatively easy to handle seamless handover. What you'd rather want would be more IMS alike, with SIP used as a common signalling protocol across a wide range of support networks (TDMA, W-CDMA, wifi, wimax...). Unfortunatly, it won't be rolled out massively before a few years. So our best bet, as of now, and since we don't have GSM carriers on the bandwagon (yet!), is probably to have SIP and GSM co-existing on the same handset in the best possible way. The best products of that kind I'm aware of are currently the wifi-enabled Nokia N- and E-Series phones. -- Nicolas Bougues Axialys Interactive ___ OpenMoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Seamless switching from gprs to wifi calling
To get back to what Mathew asked: I don't think a T-Mobile [EMAIL PROTECTED] is switching calls back and forth as you get in reach of a hotspot, and walk away from it. Secondly: this only works with T-Mobile! (for now) T-Mobile has probably set up a [EMAIL PROTECTED] call server near their GSM traffic backbone, on which your phone logs in, and through which your GSM traffic goes (with that UMA protocol) while you're logged in (in reach of a public (T-mobile) hotspot). Calls that already take place can't be re-routed I guess... Anyway, what I'm trying to say is that firstly: you need T-Mobile as your operator. Secondly: you need that T-Mobile HotSpot @home plan. Thirdly: you need a phone that's capable of routing your GSM traffic through UMA, to the T-Mobile UMA server/backbone/whatever they call it. As for the Neo1973 and OpenMoko: The phone can most likely do it, because the software just needs to know how to do it. BUT, I don't think T-Mobile will tell you how to log in. T-Mobile makes the phone software themselves for a reason. If they show you how to make a phone log in, you can make a program that logs your computer in too. So a FOSS solution for this probably won't come easily. -- Luit PS: sorry for the double post Johnson, it bounced because I mailed from the wrong account On 6/8/07, Al Johnson [EMAIL PROTECTED] wrote: Check the archives for a full discussion of this. In short GPRS is unsuitable for VoIP because of the high latencies, often in seconds. The GSM data mode is more suitable even though it's only 9600. It should be possible to have Asterisk route calls to the right VoIP endpoint, or to a GSM voice call if it can place calls to the PSTN. The trick comes in knowing when to hand over, and having a unified client that'll get Asterisk to do it. On Friday 08 June 2007 06:21, kenneth marken wrote: mathew davis wrote: Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would like it to be a little different, I don't want to use T-Mobile's service I would like to use my Wi-Fi connection to my VoIP of choice. I know this has been talked about before with some options including an Astrex box forwarding the call to your cellphone until your in range then switching to Wi-Fi but that was not a very seamless transistion from my understanding. So I guess my question is could we impliment a UMA type of technology for the neo that is customizable to use our VoIP provider? Or since that particular part is locked we wouldn't have access to that part? Just curious. When I get the phone I will be playing with trying to find a solution to this problem. I have very limited knowlege about this kind of thing. I am not an experianced programmer yet. I only have about 3 yers of indestry experiance, but none of that is mobile development and almost none of it is linux related, so I have a bit of a learnign curve so that is why I am asking the question here. while not fully up to speed on how it all works, here is my quick take on it: as long as its a voip connection, and said voip service allows two ip's to share a account and call, there should be little to no problem having both a wifi and gprs connection open at the same time as one moves about (in my experience a gprs connection can be held open but not used). hell, one may even use bluetooth if it can handle the data transfer. the problem here is that ip thing. UMA has a normal mobile phone connections as one option so therefor dont have to think about multiple ip's. it just need to have a internet connected cell so to speak, and only hand the call over when the ip based connection is fully in place. however im guessing there are some issues with going between two wifi zones/networks or something similar... so mostly you need a voip service that allows you to log in from another ip without booting the old connection off or hanging up any calls. after that its mostly a case of the client software figuring out what of the two connections to send on. or maybe just send on both, expecting the service to throw away the data thats a duplicate. something that i think is a basic feature in mobile phone systems. one funny thing is that if your using voip, and have a flat rate data plan for your mobile phone, there is no need to go wifi anyways as the mobile data connection will probably be more reliable given that its already built to do what one is trying to make the wifi system do (handover, multiple connections and overlapping
Re: Seamless switching from gprs to wifi calling
Thanks for all the input. Sounds very interesting. I didn't realize that UMA isn't VoIP. I don't want to use t-mobiles system. I was thinking of how I could do it without using their system, but the same idea. Sounds like I have got a lot fo reading ahead of me and that this problem is bigger than I thought it would be. Just to make sure I got every thing right GPRS is to slow. Inorder to get something like this to work you need the following: Client software capable of handling 2 streams sip and gsm. It also has to know when to hand over from one to the other. You also need a server that can handle the 2 streams and know when to throw away the extra data. Does that sound right? Just want to make sure I understand what you guys wrote. That IMS thing sounds interesting I will have to do some research on that. Thanks for the info. On 6/8/07, Luit van Drongelen [EMAIL PROTECTED] wrote: To get back to what Mathew asked: I don't think a T-Mobile [EMAIL PROTECTED] is switching calls back and forth as you get in reach of a hotspot, and walk away from it. Secondly: this only works with T-Mobile! (for now) T-Mobile has probably set up a [EMAIL PROTECTED] call server near their GSM traffic backbone, on which your phone logs in, and through which your GSM traffic goes (with that UMA protocol) while you're logged in (in reach of a public (T-mobile) hotspot). Calls that already take place can't be re-routed I guess... Anyway, what I'm trying to say is that firstly: you need T-Mobile as your operator. Secondly: you need that T-Mobile HotSpot @home plan. Thirdly: you need a phone that's capable of routing your GSM traffic through UMA, to the T-Mobile UMA server/backbone/whatever they call it. As for the Neo1973 and OpenMoko: The phone can most likely do it, because the software just needs to know how to do it. BUT, I don't think T-Mobile will tell you how to log in. T-Mobile makes the phone software themselves for a reason. If they show you how to make a phone log in, you can make a program that logs your computer in too. So a FOSS solution for this probably won't come easily. -- Luit PS: sorry for the double post Johnson, it bounced because I mailed from the wrong account On 6/8/07, Al Johnson [EMAIL PROTECTED] wrote: Check the archives for a full discussion of this. In short GPRS is unsuitable for VoIP because of the high latencies, often in seconds. The GSM data mode is more suitable even though it's only 9600. It should be possible to have Asterisk route calls to the right VoIP endpoint, or to a GSM voice call if it can place calls to the PSTN. The trick comes in knowing when to hand over, and having a unified client that'll get Asterisk to do it. On Friday 08 June 2007 06:21, kenneth marken wrote: mathew davis wrote: Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would like it to be a little different, I don't want to use T-Mobile's service I would like to use my Wi-Fi connection to my VoIP of choice. I know this has been talked about before with some options including an Astrex box forwarding the call to your cellphone until your in range then switching to Wi-Fi but that was not a very seamless transistion from my understanding. So I guess my question is could we impliment a UMA type of technology for the neo that is customizable to use our VoIP provider? Or since that particular part is locked we wouldn't have access to that part? Just curious. When I get the phone I will be playing with trying to find a solution to this problem. I have very limited knowlege about this kind of thing. I am not an experianced programmer yet. I only have about 3 yers of indestry experiance, but none of that is mobile development and almost none of it is linux related, so I have a bit of a learnign curve so that is why I am asking the question here. while not fully up to speed on how it all works, here is my quick take on it: as long as its a voip connection, and said voip service allows two ip's to share a account and call, there should be little to no problem having both a wifi and gprs connection open at the same time as one moves about (in my experience a gprs connection can be held open but not used). hell, one may even use bluetooth if it can handle the data transfer. the problem here is that ip thing. UMA has a normal mobile phone connections as one option so therefor dont have to think about multiple ip's. it just need to have a internet
Seamless switching from gprs to wifi calling
Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would like it to be a little different, I don't want to use T-Mobile's service I would like to use my Wi-Fi connection to my VoIP of choice. I know this has been talked about before with some options including an Astrex box forwarding the call to your cellphone until your in range then switching to Wi-Fi but that was not a very seamless transistion from my understanding. So I guess my question is could we impliment a UMA type of technology for the neo that is customizable to use our VoIP provider? Or since that particular part is locked we wouldn't have access to that part? Just curious. When I get the phone I will be playing with trying to find a solution to this problem. I have very limited knowlege about this kind of thing. I am not an experianced programmer yet. I only have about 3 yers of indestry experiance, but none of that is mobile development and almost none of it is linux related, so I have a bit of a learnign curve so that is why I am asking the question here. Thanks, Matt ___ OpenMoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Seamless switching from gprs to wifi calling
mathew davis wrote: Dear community, I am not sure if this is a widely known thing or not, but I just found out about it and had some questions about this working on the neo. T-mobile has hotspots all around my area, but have been experimenting with a new service called T-mobile HotSpot @Home. It uses a UMA (unlicensed mobile access) technology to allow phones to switch from cellular connection to Wi-Fi connection. And also makes it possible for VoIP calls. So this is something that is very interesting to me only I would like it to be a little different, I don't want to use T-Mobile's service I would like to use my Wi-Fi connection to my VoIP of choice. I know this has been talked about before with some options including an Astrex box forwarding the call to your cellphone until your in range then switching to Wi-Fi but that was not a very seamless transistion from my understanding. So I guess my question is could we impliment a UMA type of technology for the neo that is customizable to use our VoIP provider? Or since that particular part is locked we wouldn't have access to that part? Just curious. When I get the phone I will be playing with trying to find a solution to this problem. I have very limited knowlege about this kind of thing. I am not an experianced programmer yet. I only have about 3 yers of indestry experiance, but none of that is mobile development and almost none of it is linux related, so I have a bit of a learnign curve so that is why I am asking the question here. while not fully up to speed on how it all works, here is my quick take on it: as long as its a voip connection, and said voip service allows two ip's to share a account and call, there should be little to no problem having both a wifi and gprs connection open at the same time as one moves about (in my experience a gprs connection can be held open but not used). hell, one may even use bluetooth if it can handle the data transfer. the problem here is that ip thing. UMA has a normal mobile phone connections as one option so therefor dont have to think about multiple ip's. it just need to have a internet connected cell so to speak, and only hand the call over when the ip based connection is fully in place. however im guessing there are some issues with going between two wifi zones/networks or something similar... so mostly you need a voip service that allows you to log in from another ip without booting the old connection off or hanging up any calls. after that its mostly a case of the client software figuring out what of the two connections to send on. or maybe just send on both, expecting the service to throw away the data thats a duplicate. something that i think is a basic feature in mobile phone systems. one funny thing is that if your using voip, and have a flat rate data plan for your mobile phone, there is no need to go wifi anyways as the mobile data connection will probably be more reliable given that its already built to do what one is trying to make the wifi system do (handover, multiple connections and overlapping zones). ___ OpenMoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
