Coded Caching at the Edge of Satellite Networks

Abstract

Caching multimedia contents at the network edge is a key solution to decongest the amount of traffic in the backhaul link. In this paper, we extend and analyze the coded caching technique [1] in an unexplored scenario, i.e. at the edge of twotier heterogeneous networks with an arbitrary number of users. We characterize the performance of such scheme by deriving a closed-form expression of the average backhaul load and reveal a significant gain compared to other benchmark caching schemes proposed in the literature.

Edge Caching: On the Performance of Placement and Delivery Coding Schemes

“…(21) Since content in cache of relays of equal color is the same then transmission (20) or (21) will satisfy user request in the case that we have one user per relay or both u B users connected to the same R B or for any kind of combination of how u B = u W = 2 users can be connected.…”

“…In these settings, commonly referred to as non-terrestrial networks, terminals may not be equipped with direct satellite connectivity, and the intermediate tier is responsible for forwarding content from one end to the other as it is assumed in [18]- [20]. A preliminary study considering the approach of coded caching in a two-tier caching heterogenous network for an arbitrary number of users was presented in [21]. In that work caching is considered at the edge of the network (e.g.…”

“…While an initial analysis of performance when coding is applied in a two tier network were first developed in our conference paper [21], this work makes new contributions beyond those of [21] in the following aspects…”

“…• an approximation to calculate the average transmission load for each coding scheme is derived. The new expression extremely reduces the computational demanding time to evaluate the average transmission load with respect to our solution given in [21] when the number of users in the system is large, • evaluation of the outage probability for both schemes.…”

Cache Placement Optimization for Layered Video Content

“…In this scheme, the objective is to minimize the transmission from the server, which is represented by the objective function (2). The optimization problem for minimizing the average transmission rate over the backhaul link can be formulated as follows…”