Cache Subsidies for an Optimal Memory for Bandwidth Tradeoff in the Access Network

Abstract

While the cost of the access network could be considerably reduced by the use of caching, this is not currently happening because content providers (CPs), who alone have the detailed demand data required for optimal content placement, have no natural incentive to use them to minimize access network operator (ANO) expenditure. We argue that ANOs should therefore provide such an incentive in the form of direct subsidies paid to the CPs in proportion to the realized savings. We apply coalition game theory to design the required subsidy framework and propose a distributed algorithm, based on Lagrangian decomposition, allowing ANOs and CPs to collectively realize the optimal memory for bandwidth tradeoff. The considered access network is a cache hierarchy with per-CP central office caches, accessed by all ANOs, at the apex, and per-ANO dedicated bandwidth and storage resources at the lower levels, including wireless base stations, that must be shared by multiple CPs.

Incentivizing Online Edge Caching via Auction - Based Subsidization

“…Bids: We consider 9 CPs. The bidding price of each CP's bid in each time slot is proportional to the sum of the view counts of all the contents (i.e., videos) contained in the bid [3]. To compose each CP's bid in each time slot, we randomly select at least half of all the contents under consideration.…”

“…Cao et al [4] proposed to cache the most profitable contents by using auctions to allocate cache space and payments to maximize revenue. Ahmadi et al [3] applied coalition games to design subsidization from access network operators to CPs. Liu et al [18] investigated the scenario where the network operator leased small-cell resources to CPs via contract theory.…”

“…It promises ultra-low latency and traffic localization for content access, benefiting both end users and Content Providers (CPs). In lots of cases, the edge caching infrastructures are often built and managed by the Edge Network Operator (ENO) that owns and operates the edge networks, charging end users for network access [3], [4]. This scenario is illustrated in Fig.…”

“…While CDNs have seen great success in reducing content access delay and improving end users' perceived service quality, using edge caching seems to result in only negligible further delay reduction and limited addedvalue for CPs. Second, there exists no well-established revenue sharing mechanism between CPs and the ENO [3]. While CPs often pay Internet Service Providers (ISPs) (which are not necessarily the ENOs) for network connections, they do not typically pay the ENO that operates access networks.…”

“…Although there exist substantial research on edge caching algorithms and optimizations [1], [2], [10]- [15], they generally lack systematic studies of the economic interactions between different entities in the system. Prior works on edge caching incentives [3], [4], [9], [16]- [18] do not specifically focus on the interplay between the ENO and the CPs, or do not explore the auction perspective, not to mention continuous dynamic auctions, failing to address the challenges above. See Section VI for details.…”