CODEWITHSUNDEEP
androidiossmssmpp
Paulius
Paulius

Reputation: 5870

What is the maximum length of concatenated SMS in SMPP?

I'm working on an SMSC service, which is supposed to join the messages (if it finds the PDU header) and then pass that message to the next service which uses different protocols (not just SMPP) to actually deliver the message. Now, I'm a little puzzled about the max length of the message.

I have been searching, and the only thing I found about it is this, where they mention that:

Note: In theory it is possible to utilize 255 messages (39,015 characters) for a Concatenated SMS. However, 3 SMS (or 459 characters), is generally considered to be the longest length message that will be displayed on the majority of mobile handsets. CardBoardFish limit Concatenated SMS to 459 characters to ensure maximum compatibility.

Is there any official documentation speaking of this maximum limit of 3 SMS?
What kind of limits mobile OSes actually have?
And finally, what maximum length should I allow in my service?

Upvotes: 10

Views: 6671

Answers (2)

Matt Aldridge
Matt Aldridge

Reputation: 2075

Short answer is there is no official documentation. As you mentioned yourself there are theoretical limits set but that is all.

Long answer is that it depends on multiple factors:

1) Operator / SMS Aggregator

Following the store and forward principle some operators / aggregators decode and re-encode. There are a lot of implementations of SMSC's and also many more configurations. Some operators / aggregators are better than others in dealing with complex issues such as concatenated SMS. More commonly like many say around 3 parts is pretty safe these days.

2) Mobile handset GSM spec implementations

Some handset manufacturers are better than others with implementations of GSM specifications for SMS handling and have their own way of storing / decoding them. Again the less parts the better to be honest.

To conclude you should be primarily more concerned about what operators / aggregators do with your messages than the mobile OS.

As a side note beware of large concatenated messages. These parts are stored on your mobile phones SIM card and if parts are missing from a large message then these will take up space on your users phones which they cannot delete. So beware as you can very easily trash your SIM card with large concatenated messages.

Upvotes: 1

Arno
Arno

Reputation: 1253

Theoretically, the maximum payload can be 64k, or approximately 256 message parts. Practically, though, it depends on supplier. At Clickatell, for example, we split the messages into 35 message part parts before sending it on to our suppliers. Officially, though, there isn't a standard that would answer your questions.

Upvotes: 7

Related Questions