S/MIME
Secure/Multipurpose Internet Mail Extensions
S2ML
Security Services Markup Language
SASL
Simple Authentication and Security Layer
SDK
Software Development Kit
SHA-1
Secure Hash Algorithm V1
SHA1withDSA
SHA-1 with Digital Signature Algorithm
SMTP
Simple Mail Transfer Protocol
SNA
Systems Network Architecture
SOAP
Simple Object Access Protocol
SOCKS
SOCKet Secure
SPI
service provider interface
SQLJ
Structured Query Language for Java
SSL
Secure Sockets Layer
SSO
single sign-on
