Data Communication and Host Modes
RLXIC-EH
♦
Intelligent Cellular
User Manual
RadioLinx Intelligent Cellular Ethernet Gateway for HSUPA (3G GSM) Networks
ProSoft Technology, Inc.
Page 53 of 111
May 29, 2009
The TCP session will be terminated if no data is transmitted or received for the
time interval specified in
TCPT
and
TCPS
. TCPT is the number of minutes
(TCPS=0) or seconds (TCPS=1) used for this idle time-out.
Caution:
TCPT should never be 0 when using the TCP mode. A broken TCP session can result in
the modem being left with a TCP Auto Answer
TCP auto answer (S0=1|2) also allows a TCP connection request to be
"answered" when the modem is idle, not in a data session. The TCP connection
request's destination port has to match the modem's device port.
Note:
UDP auto answer may also be set simultaneously with TCP auto answer. Then, when in the
idle state, the modem will accept either a TCP connection request or UDP incoming packet, and
enter a TCP or UDP session as appropriate.
7.3.5 Hybrid
Mode
Hybrid modes are supported mainly for legacy implementations. Some previous
hybrid modes (MD=5, 6) are no longer implemented as special, unique modes.
Now that UDP auto answer (UDP Half-open, S82=2) can be enabled in
conjunction with UDP PAD mode (MD3), effectively this is the same as MD5 and
MD6 previously accomplished. Setting MD5 and MD6 are still supported, but not
recommended.
AT Command
Hybrid Mode (MD5)
Hybrid Mode2 (MD6)
MD 3
3
S82 2
2
S0 1
1
*UDPLAST 0
1
7.4 Data
Communication
Note:
The RLXIC-EH forwards messages to and from the cellular network for only ONE device per
port. The RLXIC-EH is a one-to-one gateway, and does not have advanced routing features
required to do one-to-many routing.
The primary purpose of the RLXIC-EH is to forward data from a single device
connected to one of the ports to the cellular network, and, ultimately, under most
circumstances, to the Internet in a
one-to-one
gateway configuration.
When the RLXIC-EH obtains its IP address from your cellular provider, it also
obtains the network routing information necessary to forward messages to their
routers which can then forward on from there. The RLXIC-EH then acts as a
router for the device connected to it, forwarding to or from the cellular network.
Note:
If you have a device connected to the serial port and the USB port, they will not be able to
communicate to each other. Each port is routed separately to the cellular network with one-to-one
routing for each.
Summary of Contents for RLXIC-EH
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