Short Message Service (sms) security solution for mobile devices

e. Low 
Data 
Rate 
Urban Communications 
Communications in build-up areas with tall concrete buildings is 
challenging. Satellite communications are limited because they require line-of-
sight to the satellites in order to operate properly. SMS is especially useful in 
such environments because of its store-and-forward mechanism. The SMS is 
held in the system and delivered once the device comes online. Therefore, SMS 
can complement any existing communications setup by providing an effective 
backup communications for low data rate applications such Blue Force Tracking 
in urban environments. The message delivery notification has been built into the 
SMS specification to ensure reliable delivery of SMS messages. However, there 
are no message priority mechanisms to prioritize urgent messages. Therefore, 
SMS may be suitable for use the primary war fighting net. 
f.
Secure Chat 
The ability to conduct secure text chats among tactical units may be 
useful in certain missions. Current tactical military communications are still 

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largely voice-based. Voice communications may be effective in a dynamic 
combat situation when real time conversation and feedback is crucial, and the 
soldier may be required to be constantly on the move. However, secure chat may 
be useful in silent surveillance operations or for an exchange of quick updates 
among tactical commanders. Text eliminates any ambiguities and 
misunderstandings in voice communications.
 
g. 
Encryption for Every Soldier 
It has been reported that soldiers and sailors send sensitive, 
hopefully unclassified, data such as ship movement and troop deployment to 
their love ones over the public communications network. It is important that such 
information be denied to the adversary as far as possible because the soldiers 
are likely to be deployed in other countries and using a foreign GSM 
infrastructure. Therefore, a simple application layer software encryption solution 
for SMS can provide an added level of security. The aim is not to encourage 
soldiers to divulge sensitive information over public networks. Suitable OPSEC 
policy must still be enforced. Even if the messages are non-sensitive, inferences 
can be made from a collection of such messages. Adding a layer of encryption 
makes such inferences difficult as it is less likely the unintended recipient of the 
information will be able to analyze it when it is encrypted.

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