Campbell NL200, Инструкция по эксплуатации

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NL200/201 Network Link Interface
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7.6.1 TLS Proxy Server
A TLS proxy server is a device that acts as a secure intermediary for requests
from clients seeking resources from other servers. A client connects to the
proxy server, requesting some service, such as a file, connection, web page, or
other resource, available from a different server. The proxy server evaluates
the request according to its filtering rules. For example, it may filter traffic by
IP address or protocol. If the request is validated by the filter, the proxy
provides the resource by connecting to the relevant server and requesting the
service on behalf of the client.
When the TLS Proxy Server function is enabled, 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. Any other client program that
encrypts a standard TCP connection using TLS may be used to establish a
connection with the NL200/201 TLS Proxy Server and the NL200/201 will
forward unencrypted TCP data to a datalogger. In this way, a remote TLS
client can establish a TLS connection with a datalogger.
The settings found in the TLS Proxy Server and TLS tab in
DevConfig
are used
to configure the NL200/201 TLS Proxy Server.
Two physical configurations are possible and the required settings differ
depending on the configuration chosen. The possible configurations are shown
in the following figure.
FIGURE 7-4. TLS proxy server configurations
Configuration A
In Configuration A, the NL200/201 decrypts TLS traffic and forwards the
unencrypted TCP traffic to the datalogger over the CS I/O port. The
NL200/201 is able to “learn” the IP address of the attached datalogger and will
open a TCP connection on the “learned” IP address.