What is the actual size for a sms?

What is the actual size for a sms? SearchSearch
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Anonymous
 
Posted on Thursday, July 08, 2004 - 02:07 pm:   

What is the actual size of SMS? Is it 160bytes?
Bryce Norwood - NowSMS Support
Board Administrator
Username: Bryce

Post Number: 3018
Registered: 10-2002
Posted on Friday, July 09, 2004 - 08:26 pm:   

In GSM environments, an SMS message can contain up to 140 bytes (standard 8-bit bytes) of message data.

When you send a text message, as long as the text only contains characters that are included in the GSM 7-bit character set (see http://support.nowsms.com/discus/messages/1/1103.html for the table), 160 7-bit characters are compressed into 140 8-bit bytes to produce the 160 character limit that we are so familiar with.

(Note: 160 * 7 = 140 * 8)

If you want to send a message that contains characters that are not part of the GSM 7-bit character set, such as Chinese, Arabic, Thai, Cyrillic, etc., then the text needs to be encoded in Unicode UCS-2 format where each message is limited to 70 16-bit characters. (70 * 16 = 140 * 8)

If a message is larger than 140 8-bit bytes, then there are segmentation and reassembly standards defined, where a single logical message can be sent over the air using multiple physical SMS messages. The receiving client then has the ability to reassemble the segmented message so that it again appears as a single message on the receiving device.

-bn
Anonymous
 
Posted on Saturday, July 10, 2004 - 04:12 pm:   

Thanks for your answer!
Anonymous
 
Posted on Sunday, July 11, 2004 - 06:12 pm:   

Is it mean if I saved a sms in my PC, it will occupied about 1120bytes?
Bryce Norwood - NowSMS Support
Board Administrator
Username: Bryce

Post Number: 3037
Registered: 10-2002
Posted on Wednesday, July 14, 2004 - 03:44 pm:   


quote:

Is it mean if I saved a sms in my PC, it will occupied about 1120bytes?




It depends on how it is stored. What application, what database or file format, etc. An application storing a text message on a PC might only use the number of bytes of actual text in the message.

An SMS message contains additional information (flags, timestamps, sender) ... but there is 140 bytes available for message data.

There is likely to be overhead, so it's really difficult to estimate as it is going to vary by application.