VOIP Sim Cards

Does anyone know the difference between a voip sim card and one for cell service? I understand there are three different sim cards for cell service. Can I use a regular nano sim card as a voip sim card?

I bought some nano sim cards for my iphone. I also bought a sim card writer. I suppose if I put the ip address of the server in the sim it might point the phone at the voip server.

[You] “understand” and in your other post you were “under the impression” so I am definitely curious about your sources.

I mean there is a nano sim card a normal sim card and a micro sim card. The reason I am asking about the difference between a regular sim card and a voip sim card is because while I was trying to figure out about writing sim cards I ran into some companies in Europe that are doing what I am trying to do. They talk about voip sim cards on their site. I am just having trouble findingmuch on sim cards except for phone providers advertising theirs for their service. I just need it to work over wifi without an ap. Rather it work through the sim.

I think you’ve got a wrong idea about how cellular technology works. What is wifi without an AP? Sounds like cellular data to me. Whose cellular network are you going to use? Talk to them about the data service and then you can connect over cellular to your PBX.

Perhaps the OP wants:-


I have an old Note-3 that I use inside my local network that connects to my PBX via SIP. It doesn’t have a SIM card, at all, and connects through the WiFi just fine. I don’t need a SIM to connect to VOIP when I use the WiFi connections. Now, I assign this “phone” a static IP address to limit the SIP exposure, but there have been times in the past where it was the only phone on the network that was working.

I need the phone to work anywhere there is a wifi connection world wide. Your solution may work for a phone that is only needs to work over a single dsl line or something like that. How do you assign an ip to a cell phone?

The WiFi connection , if successful, will be responsible for assigning the IP address, it might be IP4 or IP6 but it will likely not be publicly routable.

If you have connectivity through the WiFi connections, you will need a service to connect to to complete calls to the PSTN

If using WiFi, a SIM card (of any size) is moot.

I have a Asterisk/FreePBX server to connect the phone to. I am just looking to use wifi calling for now. Was hoping to be able to use the iphone over any hot spot world wide. Maybe I am asking too much. I reas somethings on the asterisk site and on some sites overseas that lead me to believe I can set up an iphone on the asterisk server and use it anywhere there is wifi. From reading these european companies they say if you put a sim in the phone it will try to connect to the server over cell or wifi. I may have to play around with some3 things to see what ways I can make this work.

Lets say I put a sim card in the phone. I think you have to program the ip address of the server into the sim card. Although

Zoiper or any other soft phone can do that. You set up the server to listen to authenticated setup from the softphone/App You set the Registrar (your server) and authentication in the softphone app, if they can connect with each other and agree you are kosher, then “chocks away”

Please give up on programming your SIM card, A) it not necessary and B) you won’t be able to.

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