code: public void enableDTLS(String hashFunction, String remoteFingerprint) {
          if (!this.dtls) {
              this.rtpChannel.enableSRTP(hashFunction, remoteFingerprint);
              if (!this.rtcpMux) {
                  rtcpChannel.enableSRTCP(hashFunction, remoteFingerprint);
              }
              this.dtls = true;
  
              if (logger.isDebugEnabled()) {
                  logger.debug(this.mediaType + " channel " + this.ssrc + " enabled DTLS");
              }
          }
      }
docs: Enables DTLS on the channel. RTP and RTCP packets flowing through this
  channel will be secured.
  
  <p>
  This method is used in <b>inbound</b> calls where the remote fingerprint is known.
  </p>
  
  @param remoteFingerprint
  The DTLS finger print of the remote peer.