3 other settings, 1 choosing the mobile telephone network – Lancom Systems 3550 User Manual
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LANCOM 3550 Wireless
Chapter 5: Setting up the UMTS profile
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EN
To ensure that the VPN connection with the network at the headquarters
is available on a continuous basis, set both the hold time for the Internet
connection and the VPN hold time to '9,999' (keep alive). This is the only
way to ensure that access from the headquarters to the UMTS-connected
network is possible at all times (e.g. for connecting branches via UMTS
where no broadband Internet access is available).
The keep alive function also requires an entry in the polling table. To do
this in LANconfig, create the entry for the appropriate connection with up
to four IP addresses in the remote network, along with the related ping
interval and the number of retries in the configuration area 'Communica-
tion' on the 'Remote sites' tab in the 'Polling table'.
If line polling is to be used to monitor the VPN connection, then it also has
to be initiated from the VPN gateway with the UMTS/HSPDA card and
must be directed towards the remote VPN gateway. The interval times for
the polling calls may have to be adjusted depending on the quality of the
connection.
Depending on the tariff, always-on Internet connections can give rise
to considerable costs, for example with time-based charging. Please
ensure that you are familiar with the details of your provider's UMTS
tariff.
5.3
Other settings
5.3.1
Choosing the mobile telephone network
Most mobile data cards are programmed to log in to their own network when
coverage is available, and there is no free choice of network.
Once the card is outside of "home network" coverage, there is normally a
choice of alternative mobile networks (i.e. roaming, in particular when in
another country). Generally speaking, the user now has a choice of network
which is to be used for the Internet connection.
In the appropriate UMTS/GPRS profile, set the option for network selection to
'manual'. The entry for the name of the desired network should be the same
as that identified by the data card's scanning procedure.