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Use compression
SSL-enabled classes in SecureBlackbox support TLS compression using DEFLATE method, as defined by RFC 3749.
To enable compression, use CompressionAlgorithms property of SSL-enabled classes.
Note, that compression is an addition to TLS 1.0 and is not supported by most SSL clients and servers. SecureBlackbox supports compression in application-level protocols, such as HTTP (in TElHTTPSClient) and FTPS (Mode Z in TElSimpleFTPSClient).