Hitachi CP-S245 User Manual page 93

Automatic Connection Break
The TCP connection will be automatically disconnected after there is no
communication for 30 seconds after being established.
Authentication
The projector does not accept commands without authentication success
when authentication is enabled. The projector uses a challenge response type
authentication with an MD5 (Message Digest 5) algorithm.
When the projector is using a LAN, a random eight bytes will be returned if
authentication is enabled. Bind this received 8 bytes and the authentication
password and digest this data with the MD5 algorithm and add this in front of the
commands to send.
Following is a sample if the authentication password is set to "password" and the
random eight bytes are "a572f60c".
1) Select the projector.
2) Receive the random eight bytes "a572f60c" from the projector.
3) Bind the random eight bytes "a572f60c" and the authentication password
"password" and it becomes "a572f60cpassword".
4) Digest this bind "a572f60cpassword" with MD5 algorithm.
It will be "e3d97429adffa11bce1f7275813d4bde".
5) Add this "e3d97429adffa11bce1f7275813d4bde" in front of the commands and
send the data.
Send "e3d97429adffa11bce1f7275813d4bde"+command.
6) When the sending data is correct, the command will be performed and the
reply data will be returned. Otherwise, an authentication error will be returned.
Command Control via the Network
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