Campbell NL200, Instruction Manual

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NL200/201 Network Link Interface
20
preferentially use AES-256, then AES-128, and finally RC4. X.509 certificates
are supported, with the exception of v3 extensions. Certificates should be PEM
format. Up to 10 certificates can be chained. 20 KB of space is provided for
certificate storage. The Private Key should also be in PEM format and, if
encrypted, use AES-256 or AES-128 (SHA).
The implementation of TLS in the NL200/201 is provided so that secure,
encrypted communications can be established between a TLS client and the
NL200/201. With the TLS Proxy Server enabled, the NL200/201 can act as a
TLS proxy server for a datalogger. The NL200/201’s TLS Proxy Server
maintains a secure TLS connection with a remote TLS client and forwards data
onto a datalogger using a standard TCP connection thus enabling
communication with TLS clients. The TLS client can be a web browser using
HTTPS or other user-supplied TLS client. This offloads from the datalogger
the intensive computations that are necessary for a TLS server to perform.
Also, with the NL200/201 configured for TLS, it can establish a secure TLS
configuration session with
DevConfig
.
In order to use TLS, the user must configure the NL200/201 with a user-
supplied TLS Private Key and TLS Certificate. The key and certificate are
loaded using
DevConfig
.
Using
DevConfig
, navigate to the Settings Editor tab and then to the TLS tab.
x
Load the user-supplied, PEM-formatted TLS Private key using the Set
TLS Key … button. A file dialog will open. Navigate to the key file
and click Open .
x
Load the user-supplied, PEM-formatted TLS Certificate using the Set
TLS Certificate … button. A file dialog will open. Navigate to the
certificate file and click Open .
x
Enter the TLS Private Key Password if the TLS Private Key is
encrypted. Otherwise, leave the setting blank.
x
After loading the key and certificate, click the Apply button. The
NL200/201 will reboot. Connect with
DevConfig
again and navigate
to the Settings Editor tab and then to the TLS tab. The TLS Status
should say Initialized .
The TLS Settings described above cannot be edited over a
standard TCP
DevConfig
link. The TLS Private Key, TLS Private
Key Password and TLS Certificate can only be edited/transmitted
over a secure
DevConfig
link (USB or TLS).
If the status of the TLS stack is Initialized , the NL200/201 will
automatically negotiate a secure TLS connection with
DevConfig
as long as the Use IP Connection option is selected.
NOTE
NOTE