38 research outputs found
Caching in Combination Networks: Novel Multicast Message Generation and Delivery by Leveraging the Network Topology
Maddah-Ali and Niesen's original coded caching scheme for shared-link
broadcast networks is now known to be optimal to within a factor two, and has
been applied to other types of networks. For practical reasons, this paper
considers that a server communicates to cache-aided users through
intermediate relays. In particular, it focuses on combination networks where
each of the users is connected to a distinct -subsets of
relays. By leveraging the symmetric topology of the network, this paper
proposes a novel method to general multicast messages and to deliver them to
the users. By numerical evaluations, the proposed scheme is shown to reduce the
download time compared to the schemes available in the literature. The idea is
then extended to decentralized combination networks, more general relay
networks, and combination networks with cache-aided relays and users. Also in
these cases the proposed scheme outperforms known ones.Comment: 6 pages, 3 figures, accepted in ICC 2018, correct the typo in (6) of
the previous versio
A Novel Asymmetric Coded Placement in Combination Networks with end-user Caches
The tradeoff between the user's memory size and the worst-case download time
in the combination network is studied, where a central server
communicates with users through immediate relays, and each user has
local cache of size files and is connected to a different subset of
relays. The main contribution of this paper is the design of a coded caching
scheme with asymmetric coded placement by leveraging coordination among the
relays, which was not exploited in past work. Mathematical analysis and
numerical results show that the proposed schemes outperform existing schemes.Comment: 5 pages, 2 figures, ITA 201