Page 81 - 5G Basics - Core Network Aspects

Core network aspects 1

1) End user S1 in the train requests a TV programme, i.e., an NDO from its TV service provider through
its LTE interface.
2) The service provider transfers the NDO to the requester. The device of S1 caches it.
3) The device of S1 announces to its neighbours the existence of the NDO through the broadcast
functions of bluetooth. The announcement is delivered to both S2 and S3.
4) The device of S1 announces to its neighbours the existence of the NDO through the broadcast
function of WLAN. The announcement is only delivered to S2, which receives two announcements
from S1 through its bluetooth and WLAN interface, respectively.
5) S2 requests the NDO from S1 via WLAN since WLAN is faster than bluetooth.
6) S1 transfers the NDO to S2. The device of S2 caches it to serve other neighbours on demand.
Figure 7-18 is a procedural diagram of DAN functions for this scenario.

1) The service provider publishes NDOs, which distributes routing information that leads toward the
NDOs.
2) The DAN network provider forwards the routing information to the end user.

3) The end user requests the NDO through an appropriate interface, which is determined based on the
routing information.

4) The DAN network provider transfers the NDO to the end user.

Figure 7-18 – Use case of multihoming with DAN

7.9.1 Benefits
DAN provides us with the capability to obtain any data in heterogeneous networks using the same ID of the
corresponding NDO. Users do not care about which media interface is active to access their favourite data in
the possible networks surrounding them, such as a bluetooth network, Infrared Data Association (IrDA)
network, WLAN or the Internet via LTE. Thus the user interface is dramatically improved. Furthermore, an
application developer can also benefit from DAN because of easy programming for network application, e.g.,
ease of access any data by its unique name.
Network operators can improve network bandwidth consumption from this service scenario, since DAN is
able to retrieve NDOs through multiple network interfaces simultaneously. Network interfaces can be also
adaptively used based on an environmental change, so that a user does not need to care about how much of
each network is currently used. Fault tolerance of communication between two DAN nodes can be achieved

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