A Privacy-Preserving Protocol for Network-Neutral Caching in ISP Networks

Abstract

By performing in-network caching, Internet Service Providers (ISPs) allow Content Providers (CPs) to serve contents from locations closer to users. In this way, the pressure of content delivery on ISPs' network is alleviated, and the users' Quality-of-Experience (QoE) improved. Due to its impact on QoE, caching has been recently considered as a form of traffic prioritization in the debate on Network Neutrality (NN). A possible approach to perform NN-compliant caching consists in assigning the same portion of cache storage to all the CPs. However, this static subdivision does not consider the different popularities of the CPs' contents and is therefore inefficient. Alternatively, the cache can be subdivided among the CPs proportionally to the popularity of their contents. However, CPs consider this information private and are reluctant to disclose it. In this work, we propose a protocol to perform a popularity-driven subdivision of the caches' storage in a privacy-preserving and network-neutral fashion. The protocol is based on the Shamir Secret Sharing (SSS) scheme and is designed to ensure a NN-compliant subdivision of the caches while preserving the privacy of both CPs and ISP (i.e., contents' popularity and caches' size are not disclosed). Through dynamic simulation, we show that the popularity-driven cache subdivision (enforced by using our protocol) outperforms several baseline approaches in terms of overall network Resource Occupation (RO) and caching Hit-Ratios. Thanks to our numerical results, we observe that the frequency of execution of the protocol has a significant impact on the RO, and that the ISP can tune this frequency to minimize its RO while introducing an acceptable data overhead. Because of this tuning, several CPs may experience a loss with respect to the hit-ratio that they would obtain by independently choosing the frequency of execution. This loss is very limited, and the employment of the protocol is therefore beneficial to all the involved parties, especially since, by using it, CPs are guaranteed that the ISP behaves in a network-neutral manner.

Privacy-Preserving Multi-Operator Contact Tracing for Early Detection of Covid19 Contagions

“…In Fig. 4, we show the trade-off between overhead and privacy with varying η ∈ [1,200], for χ ∈ [10,20,30,40]. From this figure, we observe that a very high level of privacy can be reached at a remarkable reduction of the overhead.…”

“…In this work, we exploit consolidated privacy-preserving techniques (e.g., as those employed in [10], [11]) to compute the number of contacts that a user had with positive people, while guaranteeing that users' contacts, locations and infection status are not disclosed to illegitimate parties (see subsection III-B for further details). Differently from tokenbased solutions that only detect users' proximity, our protocol allows to compute also the number of positive persons within a given place.…”

Privacy-Preserving Multi-Operator Contact Tracing for Early Detection of Covid19 Contagions

“…In this work, we exploit consolidated privacy-preserving techniques (e.g., as those employed in [11], [12]) to compute the number of contacts that a user had with positive people, while guaranteeing that users' contacts, locations and infection status are not disclosed to illegitimate parties (see subsection III-B for further details). Differently from tokenbased solutions that only detect users' proximity, our protocol allows to compute also the number of positive persons within a given place.…”

Optimal Cache Deployment for Video-On-Demand in Optical Metro Edge Nodes under Limited Storage Capacity

“…Solving for k, we obtain Equation 7where p = T S a − (n access − 1)k − (n access − 2). By approximating the value of the summation we get Equation (8).…”

“…In this work, we aim to find the optimal cache deployment that minimizes network resource-occupation; i.e., the amount of capacity occupied in the network to perform VoD content delivery, for a given investment in terms of storage capacity (i.e., under limited storage capacity available). Here, we note that recent debates about network-neutral-caching [6] have also addressed a similar problem: regulations of network neutrality force content providers to utilize a specific amount of storage capacity to perform caching [7,8]. In that case, however, network operators aim to minimize network resource occupation, subject to constraints given by network neutrality regulations, instead of by a limited monetary investment.…”