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MMS, SMS, what's the diff?


MMS, SMS, what's the diff?

Pardon the exceedingly rookie question, but what is MMS for??  I understand that pics and videos can be sent via MMS to a phone number, but can't they be sent through SMS messaging also?  Additionally, does MMS and SMS use 3G or cellular data plan broadband or do they go out using the "voice phone" path?  Thanks.

Message 1 of 5

Re: MMS, SMS, what's the diff?

SMS is a Short Messaging System.  The important word there is short.  The system was designed to allow short text messages to be sent over a system that is primarily meant for voice.  It uses the signaling channels that are used to route and direct traffic, sending a 140-byte or smaller message over those channels.  It doesn't open a data connection, but it doesn't interfere with voice.


140 bytes is small.  If you tried sending a 256-color picture of that size, it would need to be less than 12x12 pixels.  If you reduce that to 16 colors, it needs to be less than 17x17 pixels.


MMS is very different.  It stands for Multimedia Messaging System.  As you say, images, audio clips, and (very short) videos can be sent - that's the system's purpose.  MMS actually does use a data connection, so if you have data blocked, you cannot send or receive MMS messages.  If you're in a 2G-only coverage area or don't have a 3G-capable phone, you can't receive MMS messages while you're on a call (since 2G doesn't support simultaneous voice and data).  However, the data used does not count toward your data plan allowance or pay-per-use data.


I am an AT&T employee and the postings on this site are my own and don’t necessarily represent AT&T’s positions, strategies or opinions.
Message 2 of 5

Re: MMS, SMS, what's the diff?

the last paragraph regarding mms really confused me. I don't understand the sentence that says data used does not count towards your data plan allowance or pay per use data?
Message 3 of 5

Re: MMS, SMS, what's the diff?

a sms can send a maximun of 140 letters (characters) per message (some phones will allow you to go past 140 characters but when you send it it will break it down to 140 characters as 1 messag and continue till all characters are sent), a mms is a picture message that can include a picture or in some cases a audio file instead and this message can have up to 1000 characters (reference made to previous character limits applies here as well), the cost of data for a mms is cover by the pay per use mms charge or the messaging package you have for your line.
Message 4 of 5

Re: MMS, SMS, what's the diff?

In a simple language SMS is a short text message and MMS is a kind of multimedia message.

Message 5 of 5
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