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RCU 11
Frequently asked questions
Frequently asked questions
What do you have to think about to get to
the web site from the Internet?
In most cases where on has a fixed connection to the
Internet there is some kind of firewall to protect the net-
work. To access a unit inside a firewall, it must be configu-
red to let desired traffic through. To gain access to the web
site in the RCU from the Internet, port 80 (HTTP/web) must
open in the firewall and be guided to the RCU unit on the
inside.
How do I connect an RCU with a cable direc-
tly to a computer, without connecting it to a
network?
Ethernet networks can have two types of cable: straight-
through or crossover. A straight-through cable is used bet-
ween the computer <-> network equipment. A crossover
cable is used between a computer <-> another computer
or for network equipment <-> network equipment. The
RCU is counted as a computer and shall therefore have a
crossover cable if it is connected directly to another com-
puter.
Can the RCU become infected with a virus?
No. Visuses are generally always written to infect compu-
ters that run Microsoft Windows, or occasionally Linux. A
virus is written for a particular operating system or proces-
sor and can only infect the type of platform for which it is
written. An RCU does not have the same type of proces-
sor as an everyday computer, nor can it therefore become
infected.
What does ”JAVA support in a browser”
mean?
To be able to run a program written in JAVA on a compu-
ter, it must have a JVM (Java Virtual Machine) installed. A
JAVA applet on a web site requires that the browser can
use this JVM to be able to run the applet. Most current
browsers can manage this but there is not always a JVM
installed in the computer. In these cases a JVM must be
downloaded and installed for everything to work. JVMs
for many different operating systems can be downloaded
from: www.java.com. There is also a version on the supp-
lied CD.
What kind of subscription do I need for my
GSM modem?
If the telephonic data connection to the modem function is
to be used, a special subscription is required. Refer to the
“Web interface – Settings” section > “Modem”.
There is no special GSM subscription requirement for the
other functions. A cash card, normal subscription or a spe-
cial telematics subscription work well. However a cash card
must be regularly refilled to ensure continued use.
Can I surf to the product via the
GSM modem?
Yes, it is possible to call in to an RCU if you have a modem
connected to a computer and have configured the RCU to
accept this. Via this connection it is then possible to look at
the web pages and download log files.
However for this function the GSM subscription must inclu-
de a special service for telephonic data connection. Refer
to the “Web interface – Settings” section > “Modem”.
Can I fetch log files via the GSM modem? How
do I do it?
Yes, it is possible to call in to an RCU if you have a modem
connected to a computer and have configured the RCU to
accept this.
However for this function the GSM subscription must inclu-
de a special service for telephonic data connection. Refer
to the “Web interface – Settings” section > “Modem”.
Enter the address to the RCU in the browser, and add /cgi-
bin/log.csv. A log-in window will be displayed and then you
will be asked if you want to open or save the file.
Two log-in windows are displayed, why?
Unfortunately web browsers are often not perfectly inte-
grated with the JVM that is installed in the computer. In
practice the JVM (that runs the JAVA applets) does not
understand that the browser has already put up a log-in
window, and therefore puts up another one when a JAVA
applet is to be run, for safety’s sake. This will hopefully be
solved in future versions of browsers and JVMs.
I don’t get a reply when I send an SMS com-
mand to the RCU, what’s wrong?
Probably the telephone number is not registered in the
RCU, which is necessary to be able to send commands to
it. Another problem can be that there is no GSM coverage
where the RCU is located.
What does ”Network mask” mean?
An IP address is composed of 32 bits and the network
mask defines how many bits are used for the network
address. The remaining bits identify the computer on the
network. The net mask looks the same as an IP address,
e.g. 255.255.0.0 or 255.255.255.0.
What is a ”default Gateway”?
So that computers that are on separate networks (different
sub-networks) are able to communicate with each other,
routers are needed between the networks to “bridge” the
traffic. Default gateway is the name of the router that is to
be used to reach the computers that are not on the local
network. This router then sends the information on to the
destination or the nearest router that it knows about.
Which browsers work together with an RCU?
The web pages are optimised for Internet Explorer and
Mozilla Firefox. Other browsers should work well, but the
pages may look different.
What is the format of the log files?
The log files in the RCU are of CSV type. This is a usual
format for log files and is supported by such programs as
Microsoft Excel.
