Matching Items (6)
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- All Subjects: FiWi access networks
- All Subjects: Privacy
- Creators: Reisslein, Martin
Description
Fiber-Wireless (FiWi) network is the future network configuration that uses optical fiber as backbone transmission media and enables wireless network for the end user. Our study focuses on the Dynamic Bandwidth Allocation (DBA) algorithm for EPON upstream transmission. DBA, if designed properly, can dramatically improve the packet transmission delay and overall bandwidth utilization. With new DBA components coming out in research, a comprehensive study of DBA is conducted in this thesis, adding in Double Phase Polling coupled with novel Limited with Share credits Excess distribution method. By conducting a series simulation of DBAs using different components, we found out that grant sizing has the strongest impact on average packet delay and grant scheduling also has a significant impact on the average packet delay; grant scheduling has the strongest impact on the stability limit or maximum achievable channel utilization. Whereas the grant sizing only has a modest impact on the stability limit; the SPD grant scheduling policy in the Double Phase Polling scheduling framework coupled with Limited with Share credits Excess distribution grant sizing produced both the lowest average packet delay and the highest stability limit.
ContributorsZhao, Du (Author) / Reisslein, Martin (Thesis advisor) / McGarry, Michael (Committee member) / Fowler, John (Committee member) / Arizona State University (Publisher)
Created2011
Description
This dissertation is focused on building scalable Attribute Based Security Systems (ABSS), including efficient and privacy-preserving attribute based encryption schemes and applications to group communications and cloud computing. First of all, a Constant Ciphertext Policy Attribute Based Encryption (CCP-ABE) is proposed. Existing Attribute Based Encryption (ABE) schemes usually incur large, linearly increasing ciphertext. The proposed CCP-ABE dramatically reduces the ciphertext to small, constant size. This is the first existing ABE scheme that achieves constant ciphertext size. Also, the proposed CCP-ABE scheme is fully collusion-resistant such that users can not combine their attributes to elevate their decryption capacity. Next step, efficient ABE schemes are applied to construct optimal group communication schemes and broadcast encryption schemes. An attribute based Optimal Group Key (OGK) management scheme that attains communication-storage optimality without collusion vulnerability is presented. Then, a novel broadcast encryption model: Attribute Based Broadcast Encryption (ABBE) is introduced, which exploits the many-to-many nature of attributes to dramatically reduce the storage complexity from linear to logarithm and enable expressive attribute based access policies. The privacy issues are also considered and addressed in ABSS. Firstly, a hidden policy based ABE schemes is proposed to protect receivers' privacy by hiding the access policy. Secondly,a new concept: Gradual Identity Exposure (GIE) is introduced to address the restrictions of hidden policy based ABE schemes. GIE's approach is to reveal the receivers' information gradually by allowing ciphertext recipients to decrypt the message using their possessed attributes one-by-one. If the receiver does not possess one attribute in this procedure, the rest of attributes are still hidden. Compared to hidden-policy based solutions, GIE provides significant performance improvement in terms of reducing both computation and communication overhead. Last but not least, ABSS are incorporated into the mobile cloud computing scenarios. In the proposed secure mobile cloud data management framework, the light weight mobile devices can securely outsource expensive ABE operations and data storage to untrusted cloud service providers. The reported scheme includes two components: (1) a Cloud-Assisted Attribute-Based Encryption/Decryption (CA-ABE) scheme and (2) An Attribute-Based Data Storage (ABDS) scheme that achieves information theoretical optimality.
ContributorsZhou, Zhibin (Author) / Huang, Dijiang (Thesis advisor) / Yau, Sik-Sang (Committee member) / Ahn, Gail-Joon (Committee member) / Reisslein, Martin (Committee member) / Arizona State University (Publisher)
Created2011
Description
Mobile devices have penetrated into every aspect of modern world. For one thing, they are becoming ubiquitous in daily life. For the other thing, they are storing more and more data, including sensitive data. Therefore, security and privacy of mobile devices are indispensable. This dissertation consists of five parts: two authentication schemes, two attacks, and one countermeasure related to security and privacy of mobile devices.
Specifically, in Chapter 1, I give an overview the challenges and existing solutions in these areas. In Chapter 2, a novel authentication scheme is presented, which is based on a user’s tapping or sliding on the touchscreen of a mobile device. In Chapter 3, I focus on mobile app fingerprinting and propose a method based on analyzing the power profiles of targeted mobile devices. In Chapter 4, I mainly explore a novel liveness detection method for face authentication on mobile devices. In Chapter 5, I investigate a novel keystroke inference attack on mobile devices based on user eye movements. In Chapter 6, a novel authentication scheme is proposed, based on detecting a user’s finger gesture through acoustic sensing. In Chapter 7, I discuss the future work.
Specifically, in Chapter 1, I give an overview the challenges and existing solutions in these areas. In Chapter 2, a novel authentication scheme is presented, which is based on a user’s tapping or sliding on the touchscreen of a mobile device. In Chapter 3, I focus on mobile app fingerprinting and propose a method based on analyzing the power profiles of targeted mobile devices. In Chapter 4, I mainly explore a novel liveness detection method for face authentication on mobile devices. In Chapter 5, I investigate a novel keystroke inference attack on mobile devices based on user eye movements. In Chapter 6, a novel authentication scheme is proposed, based on detecting a user’s finger gesture through acoustic sensing. In Chapter 7, I discuss the future work.
ContributorsChen, Yimin (Author) / Zhang, Yanchao (Thesis advisor) / Zhang, Junshan (Committee member) / Reisslein, Martin (Committee member) / Ying, Lei (Committee member) / Arizona State University (Publisher)
Created2018
Description
Smartphone privacy is a growing concern around the world; smartphone applications routinely take personal information from our phones and monetize it for their own profit. Worse, they're doing it legally. The Terms of Service allow companies to use this information to market, promote, and sell personal data. Most users seem to be either unaware of it, or unconcerned by it. This has negative implications for the future of privacy, particularly as the idea of smart home technology becomes a reality. If this is what privacy looks like now, with only one major type of smart device on the market, what will the future hold, when the smart home systems come into play. In order to examine this question, I investigated how much awareness/knowledge smartphone users of a specific demographic (millennials aged 18-25) knew about their smartphone's data and where it goes. I wanted three questions answered: - For what purposes do millennials use their smartphones? - What do they know about smartphone privacy and security? - How will this affect the future of privacy? To accomplish this, I gathered information using a distributed survey to millennials attending Arizona State University. Using statistical analysis, I exposed trends for this demographic, discovering that there isn't a lack of knowledge among millennials; most are aware that smartphone apps can collect and share data and many of the participants are not comfortable with the current state of smartphone privacy. However, more than half of the study participants indicated that they never read an app's Terms of Service. Due to the nature of the privacy vs. convenience argument, users will willingly agree to let apps take their personal in- formation, since they don't want to give up the convenience.
ContributorsJones, Scott Spenser (Author) / Atkinson, Robert (Thesis director) / Chavez-Echeagaray, Maria Elena (Committee member) / Computer Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
A Fiber-Wireless (FiWi) network integrates a passive optical network (PON) with wireless mesh networks (WMNs) to provide high speed backhaul via the PON while offering the flexibility and mobility of a WMN. Generally, increasing the size of a WMN leads to higher wireless interference and longer packet delays. The partitioning of a large WMN into several smaller WMN clusters, whereby each cluster is served by an Optical Network Unit (ONU) of the PON, is examined. Existing WMN throughput-delay analysis techniques considering the mean load of the nodes at a given hop distance from a gateway (ONU) are unsuitable for the heterogeneous nodal traffic loads arising from clustering. A simple analytical queuing model that considers the individual node loads to accurately characterize the throughput-delay performance of a clustered FiWi network is introduced. The accuracy of the model is verified through extensive simulations. It is found that with sufficient PON bandwidth, clustering substantially improves the FiWi network throughput-delay performance by employing the model to examine the impact of the number of clusters on the network throughput-delay performance. Different traffic models and network designs are also studied to improve the FiWi network performance.
ContributorsChen, Po-Yen (Author) / Reisslein, Martin (Thesis advisor) / Seeling, Patrick (Committee member) / Ying, Lei (Committee member) / Zhang, Yanchao (Committee member) / Arizona State University (Publisher)
Created2015
Description
The integration of passive optical networks (PONs) and wireless mesh networks (WMNs) into Fiber-Wireless (FiWi) networks has recently emerged as a promising strategy for
providing flexible network services at relative high transmission rates. This work investigates the effectiveness of localized routing that prioritizes transmissions over the local gateway to the optical network and avoids wireless packet transmissions in radio zones that do not contain the packet source or destination. Existing routing schemes for FiWi networks consider mainly hop-count and delay metrics over a flat WMN node topology and do not specifically prioritize the local network structure. The combination of clustered and localized routing (CluLoR) performs better in terms of throughput-delay compared to routing schemes that are based on minimum hop-count which do not consider traffic localization. Subsequently, this work also investigates the packet delays when relatively low-rate traffic that has traversed a wireless network is mixed with conventional high-rate PON-only traffic. A range of different FiWi network architectures with different dynamic bandwidth allocation (DBA) mechanisms is considered. The grouping of the optical network units (ONUs) in the double-phase polling (DPP) DBA mechanism in long-range (order of 100~Km) FiWi networks is closely examined, and a novel grouping by cycle length (GCL) strategy that achieves favorable packet delay performance is introduced. At the end, this work proposes a novel backhaul network architecture based on a Smart Gateway (Sm-GW) between the small cell base stations (e.g., LTE eNBs) and the conventional backhaul gateways, e.g., LTE Servicing/Packet Gateway (S/P-GW). The Sm-GW accommodates flexible number of small cells while reducing the infrastructure requirements at the S-GW of LTE backhaul. In contrast to existing methods, the proposed Sm-GW incorporates the scheduling mechanisms to achieve the network fairness while sharing the resources among all the connected small cells base stations.
providing flexible network services at relative high transmission rates. This work investigates the effectiveness of localized routing that prioritizes transmissions over the local gateway to the optical network and avoids wireless packet transmissions in radio zones that do not contain the packet source or destination. Existing routing schemes for FiWi networks consider mainly hop-count and delay metrics over a flat WMN node topology and do not specifically prioritize the local network structure. The combination of clustered and localized routing (CluLoR) performs better in terms of throughput-delay compared to routing schemes that are based on minimum hop-count which do not consider traffic localization. Subsequently, this work also investigates the packet delays when relatively low-rate traffic that has traversed a wireless network is mixed with conventional high-rate PON-only traffic. A range of different FiWi network architectures with different dynamic bandwidth allocation (DBA) mechanisms is considered. The grouping of the optical network units (ONUs) in the double-phase polling (DPP) DBA mechanism in long-range (order of 100~Km) FiWi networks is closely examined, and a novel grouping by cycle length (GCL) strategy that achieves favorable packet delay performance is introduced. At the end, this work proposes a novel backhaul network architecture based on a Smart Gateway (Sm-GW) between the small cell base stations (e.g., LTE eNBs) and the conventional backhaul gateways, e.g., LTE Servicing/Packet Gateway (S/P-GW). The Sm-GW accommodates flexible number of small cells while reducing the infrastructure requirements at the S-GW of LTE backhaul. In contrast to existing methods, the proposed Sm-GW incorporates the scheduling mechanisms to achieve the network fairness while sharing the resources among all the connected small cells base stations.
ContributorsDashti, Yousef (Author) / Reisslein, Martin (Thesis advisor) / Zhang, Yanchao (Committee member) / Fowler, John (Committee member) / Seeling, Patrick (Committee member) / Arizona State University (Publisher)
Created2016