7 research outputs found
Can Negligible Cooperation Increase Network Capacity? The Average-Error Case
In communication networks, cooperative strategies are coding schemes where
network nodes work together to improve network performance metrics such as
sum-rate. This work studies encoder cooperation in the setting of a discrete
multiple access channel with two encoders and a single decoder. A node in the
network that is connected to both encoders via rate-limited links, referred to
as the cooperation facilitator (CF), enables the cooperation strategy.
Previously, the authors presented a class of multiple access channels where the
average-error sum-capacity has an infinite derivative in the limit where CF
output link capacities approach zero. The authors also demonstrated that for
some channels, the maximal-error sum-capacity is not continuous at the point
where the output link capacities of the CF equal zero. This work shows that the
the average-error sum-capacity is continuous when CF output link capacities
converge to zero; that is, the infinite derivative of the average-error
sum-capacity is not a result of its discontinuity as in the maximal-error case.Comment: 20 pages, 1 figure. To be submitted to ISIT '1
Negligible Cooperation: Contrasting the Maximal- and Average-Error Cases
In communication networks, cooperative strategies are coding schemes where network nodes work together to improve network performance metrics such as the total rate delivered across the network. This work studies encoder cooperation in the setting of a discrete multiple access channel (MAC) with two encoders and a single decoder. A network node, here called the cooperation facilitator (CF), that is connected to both encoders via rate-limited links, enables the cooperation strategy. Previous work by the authors presents two classes of MACs: (i) one class where the average-error sum-capacity has an infinite derivative in the limit where CF output link capacities approach zero, and (ii) a second class of MACs where the maximal-error sum-capacity is not continuous at the point where the output link capacities of the CF equal zero. This work contrasts the power of the CF in the maximal- and average-error cases, showing that a constant number of bits communicated over the CF output link can yield a positive gain in the maximal-error sum-capacity, while a far greater number of bits, even numbers that grow sublinearly in the blocklength, can never yield a non-negligible gain in the average-error sum-capacity
Negligible Cooperation: Contrasting the Maximal- and Average-Error Cases
In communication networks, cooperative strategies are coding schemes where network nodes work together to improve network performance metrics such as the total rate delivered across the network. This work studies encoder cooperation in the setting of a discrete multiple access channel (MAC) with two encoders and a single decoder. A network node, here called the cooperation facilitator (CF), that is connected to both encoders via rate-limited links, enables the cooperation strategy. Previous work by the authors presents two classes of MACs: (i) one class where the average-error sum-capacity has an infinite derivative in the limit where CF output link capacities approach zero, and (ii) a second class of MACs where the maximal-error sum-capacity is not continuous at the point where the output link capacities of the CF equal zero. This work contrasts the power of the CF in the maximal- and average-error cases, showing that a constant number of bits communicated over the CF output link can yield a positive gain in the maximal-error sum-capacity, while a far greater number of bits, even numbers that grow sublinearly in the blocklength, can never yield a non-negligible gain in the average-error sum-capacity