Page 41 - 5G Basics - Core Network Aspects

Core network aspects 1

For example, an external third party authority such as hierarchical public key infrastructure (PKI)
[b-IETF RFC 5280] can be cooperated with DAN to distribute public keys, or the publisher which received a
user request provides its public key with the requested data object. This is known as self-certifying, which
the user can verify whether the data object actually comes from the publisher simply by hashing the received
public key and comparing it with acquainted hashed public key value.
In principle, the data object itself is encrypted so that DAN may allow anonymous users to access it or restrict
the access by imposing authentication. The access control to the data object can be decided on the basis of
the network operator's or content provider's policy.

9.5 Mobility

DAN is recommended to allow the end hosts to communicate without establishing or managing an end-to-
end connection, thus simplifying the mobility aspects of the end terminals.

Rationale: DAN communicates using data name, which eliminates the need for end terminals to use the
address of the data object or the address of the host where the data object is located. This realizes simple
mobility management for the end hosts, especially when the location of the data object is unclear to the end
hosts, or when the data object or the host holding the data object is relocated during the communication
and a handover is required. Moreover, DAN allows the data object to be stored in intermediate nodes and
be retransmitted by the intermediate node on behalf of the end hosts to adapt to varying network conditions,
including fluctuation in data throughput and temporal disconnection during the handover.

9.6 Application programming interface
DAN is recommended to support two types of application programming interfaces (APIs) for data object
distribution and retrieval: put/get and publish/subscribe based APIs. Moreover, DAN is recommended to
support APIs that enable applications to retrieve the meta information, e.g., attributes of data object, to
enable the applications to respond to the request accordingly.

Rationale: Most fundamental APIs of DAN define how data objects are distributed to and retrieved from the
network. The put/get APIs allow applications to request and pull a data object from its serving network
element, and the publish/subscribe APIs allow applications to specify what data object is wanted by them,
and then the data object is delivered to the users as soon as it is published.

9.7 Transport
DAN is recommended to support two types of transport mechanisms, receiver and sender driven transports
of data objects.

Rationale: In the receiver driven transport, the receiver sends the requests for specific pieces of a data object
to the sender so that the senders respond to the request accordingly. In this case, the receiver is responsible
for maintaining reliable data transmission by resending requests for any missing piece of the data object. In
the sender driven transport, the sender controls sending rate of the pieces of a data object while performing
loss detection and congestion control.

10 Environmental considerations
DAN is able to provide several mechanisms for operators to reduce the network resources and energy
consumptions. First, network elements of DAN are able to respond to user requests directly rather than
routing them to other end points so that other network elements can save their network resources and
energy. Second, adaptive caching function of DAN localizes bursty traffic caused by unpredictable mobile
users. For this reason, operators do not need to over-provision the network to handle the unpredictable
bursty traffic. Therefore, the installation of unnecessary network resources can be minimized, which also
reduces overall energy consumption level.
A possible drawback is that individual network elements of DAN require additional resources (e.g., cache or
storage) which increase installation cost initially. Also, processing user requests may consume more energy.

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