Page 65 - 5G Basics - Core Network Aspects

Core network aspects 1

The operational procedures of the scenario are as follows:

1) Alice requests a named data object (NDO) from its service provider.
2) While the requested NDO is downloaded from the service provider to Alice, it can be stored on the
selected DAN elements along the downloading path, e.g., a center node of all access points close to
the end user.
3) Bob, with a mobile device, requests an NDO from the service provider. At this time, the request hits
the cached NDO on the DAN element.
4) Thus, the NDO is directly served from the DAN element, not from the service provider. Moreover,
the DAN element may process the NDO, so that its format fits the capability of Bob’s mobile device.
5) The service provider detects a flash crowd and so actively pushes popular NDOs to a DAN element
close to the flash crowd.
6) Requests from the flash crowd are directly served from the DAN element nearby.
Figure 7-2 is a procedural diagram of functions for a DAN content dissemination service.

Figure 7-2 – Use case of content dissemination with DAN
1) The content provider provides the service provider with content including all relevant meta-data.
Then, the service provider produces NDOs by naming the content based on their meta-data.
2) The service provider publishes the NDOs, which distributes routing information that leads toward
the NDOs. Moreover, the service provider provides the DAN elements with its public key, which
authorizes the DAN elements to serve the corresponding NDOs.
3) When an end user wants to access an NDO, if the NDO is available on the DAN elements, the request
is sent to the DAN element close to the end user, which holds the requested NDO in its cache or
storage (labelled (3-1) in Figure 7-2). Otherwise, the request is directly delivered to the service
provider (3-2).
4) Either a DAN element (4-1) or the service provider (4-2) supplies the NDO to the end user. The NDO
may be processed before being served to fit the capability of the device of the end user.
7.1.1 Benefits

Network operators have experienced an explosive increase in demand from mobile devices, especially those
which download all forms of multimedia traffic from the network. Flash crowds triggered by mobile users
make advance provisioning difficult for operators of networks. At the same time, mobile users tend to

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