Inter-operator handoff in GSM

[mobiletech]

Although inter-operator handover is described in the 3GPP specs, do operators actually support this capability? For example, if I am on a call in the Cingular network and I move into a T-Mobile only coverage area during the call, will my call get seamlessly handed over to the T-Mobile network (inter-MSC handover)?

Thanks.

[clock3687]

Originally Posted by mobiletech

Although inter-operator handover is described in the 3GPP specs, do operators actually support this capability? For example, if I am on a call in the Cingular network and I move into a T-Mobile only coverage area during the call, will my call get seamlessly handed over to the T-Mobile network (inter-MSC handover)?

Thanks.

Hey welcome to WA! In my experience when switching between carriers, you cant maintain a call. In your case if you have cingular are on a call, you move into a t-mobile area. The phone will drop the call off the cingular network, register on the t-mo network, and youll have to dial again once your phone is recognized on the t-mo network. I believe this is done since the carriers do not want to share revenue for calls moving in between the networks. Theres a thread on this, ill see if i can find it. While seamless call handling would be a nice thing to have, the carriers havent implimented it yet.

[CELLCOMTECH]

I doubt it. I believe it will be the same as our network. Even though ours and Alltel are CDMA they will not hand to each other. They run different S.I.D's and in most cases the frequency is also different. (800 vs 1900) The neighbor list programmed in the sites would also have to reflect a different companys sites. I do not think this is a practice in the industry even though they do have roaming agreements. If anyone knows something different please advise.

[RadioFoneGuy]

It does exist and isnt as hard as you would think. We have handoffs to Centennial (Ericcson Switch) TMobile (Nortel Switch) and Cingular (NOKIA/Nortel switch) Its called an Alien cell hand off. The handoff is seemless for the most part and can maintain calls going between the two.

We have good working relationship with out roaming partners. This should be possible in CDMA land as long as the two companies get along and are willing.

[clock3687]

Originally Posted by Cellonetech

It does exist and isnt as hard as you would think. We have handoffs to Centennial (Ericcson Switch) TMobile (Nortel Switch) and Cingular (NOKIA/Nortel switch) Its called an Alien cell hand off. The handoff is seemless for the most part and can maintain calls going between the two.

We have good working relationship with out roaming partners. This should be possible in CDMA land as long as the two companies get along and are willing.

Interesting cellone, when i moved in between the CellOne and T-Mobile networks in upstate NY, my calls werent handed off between the two services. So i guess its where the carriers want to do it, then they put it in place.

[RadioFoneGuy]

it would be up to your regional switchs to make the effort. In michigan we have had a good working relationship with Tmobile, Centennial, ATTWS and Cingular for years. We have TDMA handoff still working with Centennial. It can be nice were we have the handoffs we dont have the 850 licence and were only running 1900. 1900 doesnt cut it very well so the 850 helps fill in the hard to cover areas and we have twice the towers (PCS) than the others have so we help them cover there gaps so its works out pretty good.

[CELLCOMTECH]

It must depend on where you are located. When I first moved up here my daughter had a T-Mobile phone and it wouldn't even roam in the U.P. IT didn't pick up a signal till we were almost in Green Bay. I've also talked to a guy that has a NEXTEL phone and he has no service north of Crivitz,WI.

[CELLCOMTECH]

Sorry about the duplicate

[RadioFoneGuy]

It depends when you moved to the UP. Dobson didnt offer GSM until early 2004. I dont think (dont quote me) we roamed with Tmobile until June 04.

Another point is Tmobile only offered 1900 phones for years until this last year. Dobson is only 850 in WI and the UP in MI-1.

I had voicestream(Tmobile) when i first got out of the military. I didnt have coverage from Minnesota all the way to ST Ignace. At this time Alltel (western wireless) didnt have GSM, so I drove all the way from Montana all the way to Minnesota with out coverage.

Far as Nextel, they dont many roaming partners, I know they have a smaller company in Canada and one down south, I think its only Nextel in WI and the phone will only work on Nextel unless you have a hybrid iDEN/CDMA phone.

[Dogma]

CellOne Tech is more or less correct, especially when it comes to TDMA/GSM/AMPS networks. That is one benefit that those technologies have over CDMA networks, that ability to hand off to another carrier with a fairly good success rate.

I wish I could say CDMA networks handed off that well to different carriers. But even when the roaming partners of CDMA networks work together on a hand-off it works maybe 50% of the time. And the handoff is not soft, but a HHO. CDMA is a soft handoff technology which definately has its advantages over GSM & co., but intersystem hand off is not one of them.

[CELLCOMTECH]

I think when Nextel merged some of their equipment got shut off. At our site in Marquette the equipment is still there but is powered down. Why would you buy a market and then shut down the exsiting network to roam on someone else? The T-Mobile not roaming was about 1 1/2 years ago so I'm sure things have improved for them.

[RadioFoneGuy]

Originally Posted by Dogma

CellOne Tech is more or less correct, especially when it comes to TDMA/GSM/AMPS networks. That is one benefit that those technologies have over CDMA networks, that ability to hand off to another carrier with a fairly good success rate.

I wish I could say CDMA networks handed off that well to different carriers. But even when the roaming partners of CDMA networks work together on a hand-off it works maybe 50% of the time. And the handoff is not soft, but a HHO. CDMA is a soft handoff technology which definately has its advantages over GSM & co., but intersystem hand off is not one of them.

good input, I was sure it could be done but have not heard much about it. Hopefully WCDMA will resolve some of these issues. I wish they would run WCDMA on a smaller freq spread than 5mhz, alot of companies arent going to be able to pull that off. Myself I actually prefere the hard handoff versus a softhand off. As long as there isnt a capacity problems GSM seems to do fairly well running the old school handoff. I do like the ability of CDMA to handoff to another tower if the carrier the mobile is on gets to congested. Only draw back to this is if the carrier gets to congested to fast the mobile will drop the call before the handoff. An Alltel tech up here told me this was one of its biggest drawbacks.

Far as Nextel I dont know why they would turn off their system. Sprint really hasnt been putting too much CDMA up this way. They arent putting it in the lower pennisula due to Sprint having IPCS down here offering Spint service. This is kind of funny considering the Nextel techs down here are driving Sprint labled trucks.

[Dogma]

Originally Posted by Cellonetech

Far as Nextel I dont know why they would turn off their system. Sprint really hasnt been putting too much CDMA up this way. They arent putting it in the lower pennisula due to Sprint having IPCS down here offering Spint service. This is kind of funny considering the Nextel techs down here are driving Sprint labled trucks.

Your last tidbit makes me laugh as I have seen the same thing in Iowa and Minnesota. Former Nextel Partners technicians running around with Sprint trucks and not actually working or maintaining CDMA equipment. I think Iowa is iPCS and Minnesota is Northern PCS. The Sprint affiliates are selling the Sprint brand name.....its just a cluster IMO!

[RadioFoneGuy]

IMO Sprint should have bought their affiliates out first. IPCS has very sparse coverage here. If you come up here with a Sprint phone 1. Either stay in town or 2.dont leave the highway.

[clock3687]

Originally Posted by Cellonetech

IMO Sprint should have bought their affiliates out first. IPCS has very sparse coverage here. If you come up here with a Sprint phone 1. Either stay in town or 2.dont leave the highway.

True, but cant they fall back to alltel if necessary?

[RadioFoneGuy]

Good one, im not sure. They may do what Tmobile did for years and only offer PCS phones. If a phone has a minor whiff of a signal even thou it isnt usable its not going to let the subscriber roam. I remember time I was in the middle of nowhere and trying to put my phone in the trunk anything to force my phone on to another network but couldnt because it could see just enuff signal to stay on the originating network. Im not sure how IPCS roaming works.

[RadioFoneGuy]

Here something I found on their website. They only had a 2.3 % churn rate I thought it would be higher. I havent found anything on roaming.


About iPCS, Inc.
iPCS is the Sprint PCS Affiliate of Sprint Nextel with the exclusive right to sell wireless
mobility communications network products and services under the Sprint brand in 80
markets including markets in Illinois, Michigan, Pennsylvania, Indiana, Iowa, Ohio and
Tennessee. The territory includes key markets such as Grand Rapids (MI), Fort Wayne
(IN), Tri-Cities (TN), Scranton (PA), Saginaw-Bay City (MI) and Quad Cities (IA/IL).
As of March 31, 2007, iPCS's licensed territory had a total population of approximately
15.0 million residents, of which its wireless network covered approximately 11.4 million
residents, and iPCS had approximately 590,900 subscribers. iPCS is headquartered in
Schaumburg, Illinois. For more information, please visit the Company's website at
www.ipcswirelessinc.com.