Network Coding and Wireless Physical-layer ... - Jacobs University

116 Chapter 8: Summary, Conclusion, and Future Works
spatial probability density
2.5
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Figure 8.3: The normalized mobility component of the spatial node distribution in the
RWP model
do other nodes know that the channel is dropped?
8.2.3 Economics of UEP Network Coding
The auction problem considered in our previous work [3] is only one specific economic
problem among many. There are two more problems that we would like to investigate,
the bargaining problem and the hierarchical network coding game.
The Bargaining Problem of UEP Network Coding
The bargaining problem is a non-zero-sum game which allows some cooperation among
players. Let us consider network coding in a butterfly network in Fig. 8.4(a). Our knowledge
about UEP network coding tells us that D obtains better data quality if b 1 is of
higher priority than b 2 and every edge has the same erasure probability. Indeed, D may
have won an auction over E to obtain this network coding pattern. However, D and E
may reach an agreement that, when the edge AB alone is failing or having lots of erasures,
the network coding pattern in Fig. 8.4(b) is used instead. This is beneficial for both D
and E.
We aim at exploring the conditions under which bargaining is beneficial as well as the
optimal bargain in numerical values for each receiver in a generalized network.