ControlByWeb X-600M, Руководство пользователя

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X-600M Users Manual Appendix C: Accessing X-600M Over the Internet
way, all devices on the LAN share a single public IP address. This is called Network Address Translation
(NAT).
Port Forwarding
The router can be configured to allow outside access to the X-600M. All requests from the Internet to
any device on the local network must use the public IP address (e.g. 266.70.164.97). With only a single
IP address, TCP ports are used to identify the intended device for the incoming message.
Using the mailing address analogy, the port is similar to a post office box. The IP address specifies the
location, and the port specifies the specific recipient. Port numbers can be set to any number between 1
and 65235. However, many port numbers are reserved for specific applications and should be avoided.
As a general rule, numbers above 8000 are safe to use. All of the ControlByWeb products come from
the factory with the HTTP port set to 80, which is the standard port for HTTP. In this example, the X-
600M HTTP port will be changed to port 8000 and the WebRelay port will be changed to 8001. Once the
ports are changed in the two ControlByWeb devices, the router must be set up for port forwarding.
Port forwarding associates the IP address of each local device with an assigned port. In this example,
the address 192.168.1.25 for the X-600M would be associated with port 8000. The address
192.168.1.26 for WebRelay would be associated with port 8001. The X-600M would be accessed from
the Internet by entering the public IP address of the router, plus the port number assigned to the X-600M
in the URL window of the web browser:
http://266.70.164.97:8000
All Internet requests to the router for port 8000 would be forwarded to the X-600M. Similarly, all request
for port 8001 would be forwarded to WebRelay.
Note: When an HTTP request comes in to the router without the specific port specified
(http://266.70.164.97), the router will handle this as a port 80 request (default HTTP port). In other
words, http://266.70.164.97 is exactly the same as http://266.70.164.97:80.
Router configuration can vary widely. Some routers have the capability of translating the addresses and
the ports, which would require no port configuration change on the X-600M or WebRelay. For example,
the router would be configured so that messages sent to http://266.70.164.97:8000 would be forwarded
to http://266.70.164.97:80, which is the default HTTP port.
An example screen shot of a router configuration is given below. This setup allows the two
ControlByWeb products in the above example to be accessed remotely from the Internet.
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