Mitsubishi MELSEC-Q Series User Manual page 153

4 SET-UP AND PROCEDURE BEFORE OPERATION
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(3) Security precautions for the Web server module
The Web server module supports the basic authentication by the user name and
password (account setting) and the IP filter function (Refer to Section 4.6.6),
however, they cannot prevent illegal access from the outside completely.
When it is required to keep the programmable controller system safe against
illegal access from the outside, the user should also take preventive measures.
It is recommended to use the Web server module paying attention to the
following.
(a) To prevent illegal access, it is recommended to use the Web server module
on a LAN.
When connecting to the Internet, it is advisable to connect it via a router
and use the security function of the router.
(b) If access to the Web server module is not made for dial-up Internet
connection, disconnect the Web server module from the network. (Refer to
Section 5.4.)
(c) When making the account setting, pay attention to the following points in
order to prevent the account information (user name, password) from
missing.
1) Avoid simple setting with alphanumeric characters only. Make sure to
add symbols ($&?), etc. to set unpredictable user name and password.
2) Delete the default account since it may be used to make illegal access.
(d) Changing the default port No. (Refer to Section 4.6.3.) and configuring the
IP filter setting (Refer to Section 4.6.6.) is recommended for Internet
connection.
MELSEC-Q
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