B+B SMARTWORK SmartMotion, Configuration Manual

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4. CONFIGURATION
Continued from previous page
Item Description
MRU Specifies the Maximum Receive Unit which is the maximum size of a
packet that the router can receive in a given environment. The default
value is 1500 B. Other settings can cause the router to incorrectly trans-
mit data.
MTU Specifies the Maximum Transmission Unit which is the maximum size
of a packet that the router can transmit in a given environment. The de-
fault value is 1500 B. Other settings can cause the router to incorrectly
transmit data.
Table 21: Mobile WAN Connection Configuration
The following list contains tips for working with the 1st/2nd Mobile WAN Configuration form:
•
If the MTU size is set incorrectly, then the router does not exceed the data transfer. When
you set the MTU value low, more frequent fragmentation of data occurs. More frequent
fragmentation means a higher overhead and also the possibility of packet damage during
defragmentation. On the contrary, a higher MTU value can cause the network to drop
the packet.
•
If the IP address field is left blank, when the router establishes a connection, then the
mobile network carrier automatically assigns an IP address. If you assign an IP address,
then the router accesses the network quicker.
•
If the APN field is left blank, then the router automatically selects the APN using the IMSI
code of the SIM card. If the PLMN (operator number format) is not in the APN list, then
the router uses the default APN "internet". The mobile network carrier defines the APN.
• If you enter the word
blank
in the APN field, then the router interprets the APN as blank.
The correct PIN must be filled in. An incorrect PIN can block the SIM card.
Parameters identified with an asterisk require you to enter the appropriate information only
if this information is required by the mobile network carrier.
When the router is unsuccessful in establishing a connection to mobile network, verify
accuracy of the entered data. Alternatively, you can try a different authentication method or
network type.
4.4.2 DNS Address Configuration
The DNS Settings parameter is designed for easier configuration on the client side. When
you set the value to get from opertor the router attempts to automatically obtain an IP address
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