Page 66 - 5G Basics - Core Network Aspects

1 Core network aspects

experience unexpected delays and disruption due to content retrieval from inappropriate locations and
frequent handover.

Current CDN is based on an overlay solution provided by a small number of players, especially targeting for
limited applications, e.g., mostly based on the hypertext transfer protocol (HTTP). The lack of interoperation
among multiple CDN operators prevents scalable content dissemination in a coordinated manner, which
makes content distribution inefficient. Moreover, context awareness is not a mandatory function for a CDN,
unless an additional system component, such as deep packet inspection, is accommodated. Thus, CDN cannot
deal with the flash crowd problem in an adaptive manner.
DAN extends the geographic distribution of contents by leveraging in-network caching, which is the first order
mechanism of DAN for all types of applications. Due to the natively supported awareness feature of DAN,
content name as well as its meta-data are visible to DAN elements, so that DAN can provide content
dissemination service more adaptively in a coordinated manner compared to conventional CDNs.

7.2 Sensor networking

This service scenario involves sensor devices connected to a network and DAN elements collect sensor data
generated from the sensor devices. Sensor devices can be either wired or wireless, connecting to the network
using various wireless technologies. Sensor devices can be either fixed or mobile. They can be standalone
devices or ones attached to other systems. Sensor data can be of any kind generated by sensor devices.
DAN elements can be located anywhere in the network, from gateway nodes close to the sensor device, edge
nodes at the network edge or core nodes in backbone networks. DAN elements can be switch-based nodes
that have integrated data switching functionality or server-based nodes that are attached to the network to
process DAN traffic in an overlay manner. DAN elements collect sensor data and retain the data in their
storages. They also optionally apply processing to the data, such as conversion of data format and
aggregation of information. DAN elements then forward the data, if necessary, to the corresponding DAN
element or servers. DAN elements can be deployed by a sensor data user, a sensor networking service
provider or network operators.

Figure 7-3 depicts a scenario for sensor networking using DAN.

Figure 7-3 – Sensor networking using DAN

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