public SrtpContext()
{
_ctx = OpenSsl.EVP_CIPHER_CTX_new();
_txKey = new byte[SRTP_MASTER_KEY_LEN];
_txSalt = new byte[SRTP_MASTER_SALT_LEN];
_rxKey = new byte[SRTP_MASTER_KEY_LEN];
_rxSalt = new byte[SRTP_MASTER_SALT_LEN];
}
