## 1 Introduction
In HTTP/1.1, various research efforts have been made to deal with the unfairness problem, whose deployments varied across different network entities, that is, client-based [21; 22; 23; 24; 25], server-based [26; 27; 28; 29], or network-assisted (e.g., controller, base station, proxy, etc.) [30; 31; 32; 33; 34]. It has been proven that network-assisted solutions perform best in guiding the clients to select bitrates with respect to fairness, thanks to the ability of in-network entities to globally observe the condition of every client under its management [10; 11]. Although such studies are crucial, to the best of our knowledge, no existing work has aimed at solving the unfairness issue of HAS when employing the HTTP/2 with the server push. In this paper, we investigate the feasibility of utilizing a network-assisted approach to adaptive streaming over HTTP/2 server push. A novel framework for FAir and pUsh-enabled pRoxy-based Adaptive Streaming over HTTP/2--the **FAURAS** framework--is proposed to tackle the unfairness problem when multiple clients compete for a shared bandwidth. Specifically, assuming that all clients have the same characteristics (e.g., screen size, device type, subscription plan, etc. ), the FAURAS fairly allocates an explicit bandwidth for every client, thus effectively eliminating the bandwidth competition and avoiding the unfairness problem. Furthermore, previous studies usually do not consider the situation that clients start the streaming sessions at different time instants, causing abrupt changes of the fair bandwidth that can negatively influence the streaming experience of on-playing clients. The proposed FAURAS successfully overcomes this drawback by proactively rewrites the clients' bitrate requests on-the-fly, considering a QoE-aware strategy to harmonize the needs of uninterrupted playback and low bitrate degradation amplitude. On the other hand, we also found that existing network-assisted solutions in HTTP/1.1 fail to apply in HTTP/2 server push as they tend to drop the pushed segments when bitrate requests are overwritten, thus inefficiently making use of the feature's advantages. Meanwhile, our proposed framework is able to maintain the mechanism of the HTTP/2 server push by informing the client of the bitrate modification in advance via HTTP headers. Finally, the experimental results strongly demonstrate that the proposed FAURAS outperforms the existing works in many different criteria. The distinguished contributions of this paper are as follows:  
* A novel FAURAS framework is proposed which is the first ever network-assisted approach in adaptive streaming over HTTP/2 with server push. The FAURAS successfully solves the unfairness problem in bitrate selection among the clients, while also assisting the clients to avoid rebuffering events and to minimize bitrate degradation amplitude. * The use of the pushed segments are strictly guaranteed, therefore maintaining the mechanism and fully embracing the advantages of the HTTP/2 server push. * A detailed experimental evaluation is conducted to confirm the superior performance of FAURAS over the existing methods across various aspects. The remainder of the paper is organized as follows: Section 2 provides an overview of existing investigations and solutions to the unfairness issue in HTTP/1.1. The proposed FAURAS framework for solving the unfairness in HTTP/2 server push is presented in details and evaluated in Sections 3 and 4, respectively. Section 5 discusses the effectiveness of the proposed framework. Finally, Section 6 concludes this paper.