Digi TransPort WR11 User Manual page 585

Configuring advanced network settings
Default source IP address interface x,y
The values in these two text boxes specify the interface (None, PPP, ETH) and instance number
of that interface that IP address that XOT sockets should use instead of the interface that the
socket was created on.
Note Even when this parameter is not configured, the router uses the IP address from the
interface on which the socket was created. It uses the source address specified in this
parameter only if it will cause the traffic to match an Eroute and therefore be sent using IPsec
or GRE.
NB of XOT listening sockets
The maximum number of XOT sockets available. Use this setting to reduce the number of XOT
sockets in order to free up more general-purpose sockets for other purposes. The default value
of 0 enables the maximum number of XOT sockets available.
Maximum ACK time for XOT data
The maximum time allowance for a remote unit to acknowledge TCP data transmitted by a
unit's socket. If this timer expires, the socket is aborted. The default value of 0 disables the
timer.
Note There is no requirement for the remote unit to acknowledge received data immediately,
therefore setting this parameter to too small a value is not recommended. Some stacks delay
sending TCP ACKs in order that they can be incorporated with data sent by the application.
Do not deactivate outgoing XOT sockets when interface disconnects
When enabled, this setting sets outgoing XOT sockets not to close when the interface they are
using disconnects.
5. Configure backup IP addresses. The Backup IP Addresses section contains a table for
specifying alternative IP addresses to use when the router fails when attempting to open a
socket. The router uses these addresses only for socket connections that originate from the
router. These IP addresses provide back-up for XOT connections, TANS (TPAD answering)
connections, or any application in which the router is making outgoing socket connections.
When a backup address is in use, the original IP address that failed to open is tested at
intervals to check if it has become available again. Additionally, at the end of a session, the
router remembers when an IP address has failed, and uses the backup address immediately
for future connections. When the original IP address becomes available again, the router
automatically detects this, and reverts to using that IP address. The Backup IP Addresses
table has the following column headings:
Digi TransPort® Routers User Guide
Configure advanced network settings
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