Multimedia Messaging Service
MNC
Mobile network code
NUM lock
Number lock
PGP
Pretty Good Privacy
PIM
Personal information management
PIN
Personal identification number
SDN
Service dialing number
SIM
Subscriber Identity Module
S/MIME
Secure Multipurpose Internet Mail Extensions
SMS
Short Message Service
SMSC
Short Message Service Center
SSL
Secure Sockets Layer
TCP
Transmission Control Protocol
TLS
Transport Layer Security
Triple DES
Triple Data Encryption Standard
TTY
Teletype
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