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Process-in-Network for image provider services
Authors:
G. Urzaiz, D. Villay, F. J.Villanuevay,
J. Barbay, M.J. Santofimiay,
F. Moyay, J.C. Lopezy
Speaker :吳靖緯 MA0G0101
2011 International Conference on, P2P, Parallel, Grid,
Cloud and Internet Computing (3PGCIC)
On page(s): 237 - 241, Oct 2011
2012.05.07
Outline
• Introduction
• Related work
• Methodology
• Simple example
• Conclusion and future work
2
Introduction
• Our proposal is based on a slightly different idea called
Process-in-Network (PIN).
• Defined as the possibility that the network processes
information as it is being transmitted, seeking to take
advantage of waiting times, and idle processing capacity.
• In this article, the possible use of PIN in image processing and
analysis applications is discussed.
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Introduction
This approach may provide important benefits:
• A significant reduction in the use of the links because the
information is simplified and therefore reduces the need for
network transmission.
• This possible simplification or reduction of the amount of
information transmitted, never at the expense of a loss of
semantic content.
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Introduction
• A lower requirement of time and process at the destination end
nodes, due to the fact that the information reaches its
destination with a pre-processing level achieved by its transit
through the network.
• An enrichment of information as a result of a merger process
information as it passes through the network.
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Related work
Some general criteria that can be used to determine which
technique is better than another are as follows:
• Processing time, i.e. the time it takes to process the image
should be as small as possible.
• The amount of resources used should be as small as possible.
• Processing quality, i.e. the process should provide a quality
result.
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Methodology
• Main objective is to develop a solution that is able to transmit
images performing the processing as the information travels
through the network (Figure 1), based on the idea of using idle
resources (i.e. waiting times and idle process capacity).
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Methodology
• Our proposal is based on the Process-in-Network (PIN)
concept, simply defined as the possibility that the network
processes information as it is being transmitted.
• A preliminary PIN model has been developed including three
main features:
• pre-processing
• simplification of information
• information enrichment
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Methodology
• PIN considers two modes of operation:
• Packet-by-Packet (PbP) mode
• Block-by-Block (BbB) mode
• A packet is a single information unit, and a block is defined as
a group of one or more packets that may be processed as a
whole.
• Image processing requires to run PIN in a BbB basis.
• Every piece of the image is considered as a block.
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Methodology
• A control packet is added at the beginning of the transmission
of the image piece, indicating the block identifier and the total
number of packets that are part of the block.
• Each node that receives a packet PIN control opens the
corresponding block buffer, and is ready to receive packets for
that block.
• A block ID field is added to each packet, in order to identify
packages that are part of the same block.
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Methodology
• PIN has several requirements:
• Information may be divided in pieces
• Information process may be divided in phases
• Network nodes may be accessible and be able to perform
some process
• The nodes must have enough storage capacity
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Simple example
• The original image that is shown in Figure 2, and let the
objective be a size reduction.
• In this example, a very simple method is used to reduce the
size of the image, consisting in dividing the image in several
pieces and process them individually.
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Simple example
• In this example, 5 phases are defined as follows (Figure 3):
• Phase 0: the original image is divided in four pieces of the
same size each, but no size reduction has been done yet.
• Phase 1: First piece (up-left) is reduced in size.
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Simple example
• Phase 2: Second piece (up-right) is reduced.
• Phase 3: Third piece (down-left) is reduced.
• Phase 4: Fourth piece (down-right) is reduced. Full process
is finished.
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Simple example
• It is important to say that in this example, two PIN benefits are
clearly identified:
• Pre-processing, due to the fact that the image will arrive to
the destination nodes with certain level of preprocessing
• Information reduction, because the size reduction takes
place in the network and therefore less information is sent
• Used three different network topologies (Net5, Net10, Fish).
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Simple example
• The objective was to send an 8192x6144 image thru the
network and reduce it to half of its original size.
• The general activities are now as follows:
• Divide the image in pieces
• Send all them thru the network
• Receive the pieces at the destination node
• Resize the pieces that were not processed in the network
• Join all the pieces in one single image
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Simple example
• Results are summarized in Table 2 and graphically represented
in Figure 4.
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Simple example
• The intention is to reduce congestion by simplifying the
information as it travels over the network, and thus reducing
the load on the network.
• However, for certain network conditions it is possible that PIN
could mean a greater burden to the network, causing an even
higher level of congestion.
• As mentioned before, PIN offers the possibility to take
advantage of waiting times and idle capacity, but it is
important to make sure that conditions are appropriate for PIN.
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Conclusion and future work
• A proposal is presented to use PIN when sending an image thru
the network.
• The approach here presented may be generalized not only for
image processing applications but also for video processing.
• In this case, technologies and standards such as Scalable Video
Coding (SVC) and the MapReduce programming model could
be both very helpful.
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Conclusion and future work
• A feedback mechanism could be implemented in order to
dynamically adjust QoS or QoE for an specific user at the
destination node.
• It may be possible to dynamically adapt Quality-of-Experience
(QoE) of a user at the destination node.
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Conclusion and future work
• A similar feedback mechanism may be included as part of the
PIN mechanism (Figure 6) and make all the necessary QoS
adjustments based on the feedback line.
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