Wireless Future - Telenor

With either of the solutions described above, the
user should be able to dynamically change one
or more of the output and input devices during
a session by communicating with his Virtual
Terminal.
6.3.2.2 Direct Connection between the
Devices and the Service
Another solution is to establish a connection
directly between the utilized service and the
user’s devices. During the initiating phase a
“signal link” between the service and the Virtual
Terminal is established. The Virtual Terminal
will then tell the service how the user wants the
service to be served, e.g. which devices the user
wants to use for different types of streams,
which devices to be used for voice, which for
video and which for text. These streams will
X:User
X:User
Telektronikk 1.2001
1:Device
2:Device
3:Device
2:Device
ISUP
Gateway
then go directly to the devices, instead of via
the Virtual Terminal.
This solution can make more efficient use of network
resources, especially when the user and the
utilized service are both located on a visiting
network. But on the other hand the dynamic use
of multiple devices and changing of devices during
a session is difficult because the Virtual Terminal
cannot do any rerouting of the streams
when the user wants to use multiple devices. For
example, it will be difficult for the user to switch
from a mobile device connected to the GSM network
to an IP telephone connected to an IP network
if the mobile phone has a direct connection
with the service. On the other hand, this can be
achieved if the mobile device and the service are
connected via the Virtual Terminal as described
Gateway
PSTN/ISDN
SIP/H323
1:Device
Bluetooth
Gateway
ISUP
Mobile Network
3:Device
Piconet/Personal
Area Network
SIP/H323
IP-based
Network
SIP/H323
IP-based
Network
A:Service
X:Virtual
Terminal
A:Service
X:Virtual
Terminal
Figure 15 Connection directly
between devices and services
Figure 16 Some devices do
not have network connection
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