Information Technology Reference
In-Depth Information
IEEE 802.16/WiMAX Networks
for e-Health Services:
Advantages and Issues
layer is forwarded to service data units (SDUs)
for servicing MAC connections for classified
packets with similar service demands. Depending
on number of users and supported applications, a
range of service connections of the same category
may significantly vary during active communica-
tion providing greater flexibility. WiMAX also
supports scheduling entity which performs two
major functions:
Users of fixed and mobile Telemedicine applica-
tions can access services via IEEE 802.16/WiMAX
technology and hence, due to the guaranteed large
available bandwidth considerably reduce the trans-
mission delay for such telemedicine applications as
ultrasound and radiology images. High bandwidth
according to the (Niyato, 2007) can as well help
to support various types of telemedicine traffic
simultaneously. Support of the different QoS
types allows transmission of medical data with
higher efficiency. IEEE 802.16/WiMAX standard
allows application of encrypted functionalities via
the MAC layers security features for healthcare
data transmission.
One of the main issues related to application
of IEEE 802.16BWA based technology for tele-
medicine applications is service mapping (Niyato,
2007). It is proposed to map type of transferred
medical data to the appropriate service class. The
mapping scheme is as follows:
•
Isolation of packets forwarded to different
service classes to separately form queues
with defined QoS parameters,
•
Allocation of available system resources
between dynamically-added or rejected us-
ers connections.
The standard states that scheduling in BS is
fully responsible for DL and UL resource alloca-
tion but still each SS has its own UL scheduling
mechanisms to form transmission policy based
on upper layer QoS requests with full control and
management performed at BS.
To keep BS informed of the SSs actual band-
width and QoS needs, the standard establishes
grant-request communication process between BS
and SSs respectively. Depending on QoS classifi-
cation each SS has a group of requested opportu-
nities to apply for available bandwidth resources
to BS. Scheduling in WiMAX has to accumulate
sufficient informative data such as power level,
data rates, QoS requirements, communications
activated, user's number and its priority to assign
time slots and burst profiles to packets awaited
in queues for transmission. Although the set of
functionalities and recommendations specified
for QoS support in WiMAX are conceptually
approved, the scheduling design and explicit
structure is left up to vendors and research bod-
ies for further development and implementation.
Further, we will explore these areas and apply
our results for efficient video distribution over
WiMAX networks.
•
Allocate UGS type of QoS to the biosignal
traffic and voice conversation;
•
rtPS type of service for the video
transmission
•
nrtPS - to the file transfer, such as x-ray
images and ultrasound results;
•
BE is to be allocated for the database ac-
cess, e-mail exchange and web.
In the rest of the section a new sufficient video
distribution technique over IEEE 802.16 Network
is introduced for e-Health applications.
Distribution Framework
and Simulation Model
A new concept is proposed to utilise object orien-
tation of MPEG video streams for segmented dis-
tribution over IEEE 802.16 QoS-supported MAC
Search WWH ::
Custom Search