Advanced Video Distribution for Wireless E-Healthcare Systems - E-Healthcare Systems and Wireless Communications - page 359

Paradigm #1: Design Global Properties
That Arise From Local Behaviours

(DHCP) (Droms, 2009) in the field of an IP ad-
dress allocation. This protocol allows users to
configure their own IP address settings. By using
this protocol, computers become capable of obtain-
ing IP addresses from the server and can adapt to
changes. The IPv6 standard (Deering & Hinden,
2009) makes possible self-configuration which
reduces network administrations, that is needed
to install dedicated DHCP servers. It is achieved
simply by combining the prefix with MAC ad-
dress unique identifier. This approach has some
aspects of self-organisation such as “local com-
munication” and absence of the dedicated server.
The Transport Control Protocol (TCP) (www.
faqs.org, 1991) and its mechanism of congestion
control is another example of self-organisation: it
reduces the rate if congestion occurs and increases
it if packets arrive without any error. This manner
of traffic adaptation is decentralised and does not
depend on the network scale.
These above examples illustrate the concept of
self-organisation in communication systems and
are widely used in wireless networks. Therefore,
these protocols should be selected as an integral
part of the proposed e-Health network.

Each local network has its own local properties
and “set of rules” (in case of e-Health services
- wireless standards) but none of these entities
can be in charge of the global network organisa-
tion. In other words, if a global network is not in
conflict with the local properties, and if desired
global network properties are applied to the lo-
cal entities, it should lead to the desired network
functionality. Data provided by the local sensor
network (e.g. data collected from the patient at
home) should be delivered, stored and analysed
in the global network. However, while the local
network should be aware of protocols required for
collecting data, the overall global network does
not need to know the solution for the local net-
work management system. In this case the routing
algorithm adaptability to different requirements
of the traffic is essential in the WLAN bandwidth
constrains.

Paradigm #2: Perfect vs. “Zero”
Coordination and Fidelity
of Communications

Design a Self-Organised Network
Function for e-Health Services For the wireless sensor network it is important to

have a perfect coordination among nodes, because
of the nature of the e-Health network. Moreover,
in a real life scenario it is almost impossible to
obtain a fully self-organised network. Therefore,
in many practical applications where the perfect
coordination is essential the concept of the cen-
tralised control of all the sensors is applied. This
centralised approach has the advantage of perfect
coordination and the disadvantage is in the lack
of robustness when failure happens. This style of
coordination is often used by a system with the
centralised approach. Another extreme case of a
self-organised network is illustrated by a network
with “zero” coordination among sensors. In this

One of the most interesting questions is which
one of the known properties of “self-organisation”
can be applied on the e-Health environment.
This requires a special approach that can lead to
designing of a set of rules. Our aim is to design a
“self-organised” network especially for the wire-
less e-Health sensor networks by proposing rules
and defining properties of the network. These
can be summarised in three important paradigms
(Prehofer & Bettster, 2005; Zvikhachevskaya &
Mihaylova, 2009):