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I'm curious just how much data an iMessage sends in reality. I only have a 2 GB data plan so every bit of data I can save helps.
 
I'm curious just how much data an iMessage sends in reality. I only have a 2 GB data plan so every bit of data I can save helps.

I restored my phone 13 days ago and I've used 8MB of cellular data. Of course, that doesn't really say much, because I'm on WiFi when I'm at work and when I'm at home.

It'll also depend on usage. I don't typically send or receive video messages, but I do get some pictures. 95% of the time, it's just plain old text.
 
So if I was using an Android device these same iMessages would actually be SMS (text) messages that would be "free"?
It's not iMessage if it involves an Android device on either end.

I'm curious just how much data an iMessage sends in reality. I only have a 2 GB data plan so every bit of data I can save helps.
Depends on the data you send. For text 1 character is 1 byte. There's probably a bit of overhead as well. You'd just have to monitor your usage to be certain. If you're really worried over it you can just disable iMessage but odds are that your data hogs lie elsewhere and that you should be concerned over them instead.
 
It's not iMessage if it involves an Android device on either end.

I think you missed what I was saying here. If I was just sending SMS messages on an Android device there would be no charges for it. But... since it uses iMessage when texting to another iPhone it uses data. That's all my point was.
 
You would have to be sending a ton of high quality pics and/or videos for iMessages to add up to a significant amount of usage on your data plan.

My friends and I send pics and videos quite often to each other and it only totaled up to around 80MB of cellular data usage my last cycle.

Unless some of you are on one of those 200-300MB data plans. In that case you might want to just turn cellular data off except in case of emergency.
 
I think you missed what I was saying here. If I was just sending SMS messages on an Android device there would be no charges for it. But... since it uses iMessage when texting to another iPhone it uses data. That's all my point was.

Except there are charges for it, you pay for your texting plan or you pay for individual texts. It may be built into your "shared" plan, but you're still paying for it either way.
 
I think you missed what I was saying here. If I was just sending SMS messages on an Android device there would be no charges for it. But... since it uses iMessage when texting to another iPhone it uses data. That's all my point was.

texting plans cost money? lol

how does rockitdog not know the answer to this?
 
SMS uses a few packets of data interlaced between the rest of the cellular data. Some (most?) carriers don't count MMS as data usage in their plans.

SMS does not use any part of the cellular data. It makes use of the signalling channel on a circuit switched GSM radio signal. The SMS message has to fit within the specification of the signalling channel and is why the size of these messages are limited. The signalling channel is used only to set up a call and is available for use outside of this.
 
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I'm curious just how much data an iMessage sends in reality. I only have a 2 GB data plan so every bit of data I can save helps.

An iMessage uses a very small amount of data per message. There's no distinct answer as the consumption varies depending on the length of the message, if a picture was send, video and so on.

I currently have a 1GB data plan and send a large amount of iMessages and it barely effects my data.
 
SMS does not use any part of the cellular data. It makes use of the signalling channel on a circuit switched GSM radio signal. The SMS message has to fit within the specification of the signalling channel and is why the size of these messages are limited. The signalling channel is used only to set up a call and is available for use outside of this.

Analogue SMS is circuit switched. Digital SMS is not and does use one packet of data with a MTU of 1500. Nearly every part of the world switched to digital cellular devices in the mid-2000s. Digital cellular devices can fallback to using circuit switched SMS in the event they cannot send the SMS packet. However, carriers prefer that not happen as it creates a larger overhead on the tower.
 
I'm curious just how much data an iMessage sends in reality. I only have a 2 GB data plan so every bit of data I can save helps.

From THIS THREAD

I was curious at least to get an order of magnitude when it comes to data used by iMessage. So I fired up tshark and watched the "wire" while sending an iMessage to friend. The message itself consisted of "Test" as the subject and the body was "Test message".

Bottom line:
1,042 bytes were sent
498 bytes were received.

These were actual bytes on the "wire" so EVERYTHING is included. The whole sequence is via https from my iPhone 4 on WiFi and 17.149.36.84 which by the way resolves to nk11p01st-courier014-bz.push.apple.com.

Note that the reason I'm calling this test quick and dirty is that it was the third or fourth iMessage that I sent within about 5 minutes. I believe that some of the normal Certificate / key exchange / Handshaking was done on the first message and cached. I didn't see any of that "stuff" during subsequent messages.

Note that the message was VERY short, however adding only text to that isn't going to drastically increase its size (in terms of a per message data use). Don;t forget pictures and video though. Data usage goes completely out the window here. But with JUST text, you really need not worry. You'd have to send/recieve upwards of 1000 messages to hit even 1mb.
 
Analogue SMS is circuit switched. Digital SMS is not and does use one packet of data with a MTU of 1500. Nearly every part of the world switched to digital cellular devices in the mid-2000s. Digital cellular devices can fallback to using circuit switched SMS in the event they cannot send the SMS packet. However, carriers prefer that not happen as it creates a larger overhead on the tower.

You indicated that the SMS messages are carried on the data network. The data network has evolved from GPRS, EDGE, 3G and now LTE. The SMS messages are not carried on any of these services but on the control channels of the voice facility and is part of signalling system 7. Digital Cellular makes no difference to that statement.
 
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Then whats the advantage of iMessage if regular text message is free?

iMessage made the most sense when we had unlimited data, and texts cost. Now it's the opposite. Data is costly and texts are free :)

However, it's still a cheaper choice for international comms, plus of course it allows talking to users of non-cellular devices like an iPod touch or iPad.

It's also about locking users into something that gets popular, just as BBM did.

SMS is still circuit-switched; each message is essentially a very short phone call and that's why it's charged differently from other data.

This is correct.

An SMS requires carriers to do everything they have to do for a voice call: interconnect with each other, correlate charges for the service, find the recipient wherever they are around the world, authenticate them, and finally set up a switched connection to send the data.

But more than a voice call, they also have to store a text if the recipient isn't available, and then forward it when a carrier somewhere finds the target user. And send a receipt back the other way if requested.

Carriers usually allow SMS to come/go via an email gateway as well.

And SMS "hitches a ride" with the radio pinging to and from the tower. It is rather efficient because it is using waves that are being transmitted no matter what.

It only "hitches a ride" from the FINAL tower to the target phone, and ONLY AFTER there has been a phone call like setup and authentication.

The "hitch" is the absolute tiniest piece of the entire transfer from phone to phone.

MMS actually uses data, technically speaking, though it doesn't count against your data allotment.

It doesn't use your data allotment because it's NOT internet data. That's why SMS works even on dumb cell phones without data plans. No internet involved.

Carriers charging for text messages is the biggest sham ever. It literally costs them NOTHING, since they require you to have some sort of voice plan anyway. The thing is, people pay for convenience.

Incorrect. They charge for text messages not only because of all the overhead equipment needed to handle billions of them a day, but because they are actually miniature calls with all that that entails. Voice plans used to be charged at about 5 to 10 cents per minute. That's where text charges came from.

Many people heard that the message is stashed into a control packet at one point, and are misled into thinking that's true throughout its entire journey.

Nope. That's like claiming that a FedEx overnight package should be free because it only rode in the hands of the delivery person from his truck to your door. That totally ignores everything else that took place to get it that far.
 
So can I still send the text as a regular message instead of imessage to someone with the iphone?
 
Oh..ok, thanks for explaining how the iMassge works. I am keeping it on but good to know all the technical details.
 
I see no reason not to use iMessage. It's one of the benefits of using Apple products. Text your contacts from your iPhone, iPad, or Mac in any country. The amount of data that it uses is negligible unless you're sending lots of large videos.
 
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