24 research outputs found
Service quality assurance for the IPTV networks
The objective of the proposed research is to design and evaluate end-to-end solutions to support the Quality of Experience (QoE) for the Internet Protocol Television (IPTV) service. IPTV is a system that integrates voice, video, and data delivery into a single Internet Protocol (IP) framework to enable interactive broadcasting services at the subscribers. It promises significant advantages for both service providers and subscribers. For instance, unlike conventional broadcasting systems, IPTV broadcasts will not be restricted by the limited number of channels in the broadcast/radio spectrum. Furthermore, IPTV will provide its subscribers with the opportunity to access and interact with a wide variety of high-quality on-demand video content over the Internet. However, these advantages come at the expense of stricter quality of service (QoS) requirements than traditional Internet applications. Since IPTV is considered as a real-time broadcast service over the Internet, the success of the IPTV service depends on the QoE perceived by the end-users. The characteristics of the video traffic as well as the high-quality requirements of the IPTV broadcast impose strict requirements on transmission delay. IPTV framework has to provide mechanisms to satisfy the stringent delay, jitter, and packet loss requirements of the IPTV service over lossy transmission channels with varying characteristics. The proposed research focuses on error recovery and channel change latency problems in IPTV networks. Our specific aim is to develop a content delivery framework that integrates content features, IPTV application requirements, and network characteristics in such a way that the network resource utilization can be optimized for the given constraints on the user perceived service quality. To achieve the desired QoE levels, the proposed research focuses on the design of resource optimal server-based and peer-assisted delivery techniques. First, by analyzing the tradeoffs on the use of proactive and reactive repair techniques, a solution that optimizes the error recovery overhead is proposed. Further analysis on the proposed solution is performed by also focusing on the use of multicast error recovery techniques. By investigating the tradeoffs on the use of network-assisted and client-based channel change solutions, distributed content delivery frameworks are proposed to optimize the error recovery performance. Next, bandwidth and latency tradeoffs associated with the use of concurrent delivery streams to support the IPTV channel change are analyzed, and the results are used to develop a resource-optimal channel change framework that greatly improves the latency performance in the network. For both problems studied in this research, scalability concerns for the IPTV service are addressed by properly integrating peer-based delivery techniques into server-based solutions.Ph.D
Mobility Study for Named Data Networking in Wireless Access Networks
Information centric networking (ICN) proposes to redesign the Internet by
replacing its host-centric design with information-centric design.
Communication among entities is established at the naming level, with the
receiver side (referred to as the Consumer) acting as the driving force behind
content delivery, by interacting with the network through Interest message
transmissions. One of the proposed advantages for ICN is its support for
mobility, by de-coupling applications from transport semantics. However, so
far, little research has been conducted to understand the interaction between
ICN and mobility of consuming and producing applications, in protocols purely
based on information-centric principles, particularly in the case of NDN. In
this paper, we present our findings on the mobility-based performance of Named
Data Networking (NDN) in wireless access networks. Through simulations, we show
that the current NDN architecture is not efficient in handling mobility and
architectural enhancements needs to be done to fully support mobility of
Consumers and Producers.Comment: to appear in IEEE ICC 201
CLKS: Certificateless Keyword Search on Encrypted Data
Keyword search on encrypted data enables one to search keyword
ciphertexts without compromising keyword security. We further investigate this problem and propose a novel variant, dubbed certificateless keyword search on encrypted data (CLKS). CLKS not only supports keyword search on encrypted data, but also brings promising features due to the certificateless cryptography. In contrast to the certificated-based keyword search, CLKS requires no validation on the trustworthy of the public key before encrypting keywords; in contrast to the identity-based
keyword search, CLKS prevents the key issuer (e.g., key generator center) from penetrating any information on keyword ciphertexts by leveraging the capability of accessing all data users’ (partial) private keys. Specifically, we rigorously define the syntax and security definitions for CLKS, and present the construction that is provably secure in the standard model under the Decisional Linear assumption. We implemented the proposed CLKS scheme and evaluated its performance. To the best of our knowledge, this is the first attempt to integrate certificateless cryptography with keyword search on encrypted data