CMG-DCM
The options will take effect immediately whenever possible. Some changes may
take some time to complete, since services may need to be restarted. The gcfgdbset command performs only simple checks on the new value, so you should check the syntax of the option carefully.
Wi-Fi
Optionally, a DCM may be supplied with 802.11
•In ad hoc mode, data packets are sent out over the wireless connection indiscriminately and are received by all machines on the network. This is the simplest style of
•In infrastructure mode, dedicated 802.11 hubs collect data packets, collate, and distribute them efficiently around the network. These hubs may also act as transparent extensions to existing (wired) TCP/IP networks.
The DCM is capable of running in either situation, depending on your requirements. As far as the computers on the network are concerned, there is no difference between a TCP/IP network running over Ethernet and one using 802.11 connections, or a mixture of the two.
Once the 802.11 system is running, you will need to run a DHCP service on your network, or manually set the IP address of the DCM as above.
Connecting to the Internet
If the local network is already connected to the Internet through some other means (perhaps through a gateway machine), you can create a default route with
gcfgdbset net.eth.0.gateway
where
The DCM can perform more complex routeing if required. See “Static routes” in Section 4.4 for more details.
As supplied, the DCM module will accept requests to its
If the instrument is located on a private network, you may be able to connect to it from the wider Internet by using a feature implemented by SSH known as tunnelling. You can use this technique to connect to the DCM through a chain
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