eLutions iR1600, Configuration Manual

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IR1600 Modem
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Retransmit Timeout
As part of its error recovery mechanism, TCP may need to resend a packet. It knows to
resend the packet because it did not receive an acknowledgement when it previously sent
the packet. When selecting this value, you should keep in mind the transit time for the
packet to be sent to the remote node, and for the transit time for the acknowledgement to be
received from the remote node.
Care should be taken to not set this number too high, since this may cause an inordinate
amount of time to recover from an error and the remote system may view this as an error.
We recommend setting the value in the range of 5 to 10 seconds.
NOTE: The value is only used for TCP connections and has no effect in UDP mode. The value for this
parameter must be less than the socket timeout.
Keep TCP Client Socket
Open
In TCP Client mode, the iR1600 does not open a connection to the server until it has
received data from the DTE (and has met one of the events defined in the PAD
configuration). This ensures that a connection won’t be opened that will then sit idle and
unused.
There are times when this is not always advantageous. For example, if the DTE has no
data to send, but the server does want to send data to the DTE, the server will have to wait
for the DTE to have data before the connection is opened.
To set the iR1600 where it will immediately open the socket and to keep it open
(regardless of whether the DTE has data to send) you should set this value to Yes.
NOTE: This setting will work in conjunction with the socket timeout. A socket timeout may occur,
causing an open connection to be closed.
This parameter is not used in TCP Server mode since other PCs. Similarly controls the
socket, this parameter is not used in the UDP connection.
Access Control List
Configuration
When the modem is in either Gateway or AVL operating mode, it will act as a “listener”
and will use the ACL to query for available IP addresses. This option provides access to
the Access Control List Menu where IP addresses can be specified.