Jawwad Shamsi

Data-Intensive Cloud Computing: Requirements, Expectations, Challenges, and Solutions

Data-intensive systems encompass terabytes to petabytes of data. Such systems require massive storage and intensive computational power in order to execute complex queries and generate timely results. Further, the rate at which this data is being generated induces extensive challenges of data storage, linking, and processing. A data-intensive cloud provides an abstraction of high availability, usability, and efficiency to users. However, underlying this abstraction, there are stringent requirements and challenges to facilitate scalable and resourceful services through effective physical infrastructure, smart networking solutions, intelligent software tools, and useful software approaches. This paper analyzes the extensive requirements which exist in data-intensive clouds, describes various challenges related to the paradigm, and assess numerous solutions in meeting these requirements and challenges. It provides a detailed study of the solutions and analyzes their capabilities in meeting emerging needs of widespread applications.

QoSMap: Achieving Quality and Resilience through Overlay Construction

We describe QoSMap, an overlay construction mechanism which computes high quality overlay networks for applications having stringent constraints on hop-degrading QoS metrics and provides resilience against the Internet’s unpredictable network behavior. QoSMap implements three features to achieve the QoS and resiliency goals. In order to provide high QoS, it constructs overlay communication edges with short but efficient underlay paths. In case of QoS violations due to changing network conditions, QoSMap utilizes supplemental backup paths, which are specifically constructed in order to extend overlay lifetimes. QoSMap also avoids nodes that have experienced recent QoS failure, further improving the resilience of the overlays. PlanetLab experiments prove the ability of QoSMap to construct efficient and resilient overlays for applications with stringent QoS constraints of latency and packet loss for a variety of topologies. QoSMap-constructed overlays significantly outperform overlays constructed without the three QoSMap features. The results also reveal the usability and effectiveness of QoSMap to construct near-optimal solution in a short amount of time, compared to the optimal solution which has a very high time complexity.

QoSMap: QoS aware Mapping of Virtual Networks for Resiliency and Efficiency

We describe QoSMap, an efficient and flexible mechanism for constructing virtual networks on a shared Internet substrate for applications having stringent QoS and resiliency requirements. Applications specify desired overlay topology and weighted network characteristics which serve as resource constraints desired by the application in meeting the QoS expectations. QoSMap uses these constraints to select an overlay consisting of high quality direct paths between nodes from a pool of candidate nodes and paths. In addition to the required overlay topology constructed from direct paths between nodes, QoSMap provides path resiliency by constructing alternate one-hop overlay routes via intermediary nodes having paths that meet or exceed the resource constraints. As a case study, we utilized QoSMap to form an overlay for an application requiring constraints on message delay and loss rates. We describe the design of QoSMap and show that it leads to higher quality and more resilient overlays than does a mechanism which addresses only the minimum QoS requirements of the application.

TACON: tactical construction of overlay networks

Internet-based overlay networks are likely to demonstrate poor performance when deployed on the Internet without consideration of topological and link properties. We introduce a new method for tactical construction of unstructured overlay networks which exploits a minimal landmark infrastructure to align the overlay with the underlying network. Our framework results in well-connected overlays which can better meet the growing demands of current applications. We demonstrate, using simulation, that our approach yields reduced latency, better connectivity and higher availability of resources than conventional overlay systems and other landmark-based approaches, thereby providing a scalable and efficient approach for overlay construction.

Smart City Architecture: Vision and Challenges

The concept of smart city was born to provide improved quality of life to citizens. The key idea is to integrate information system services of each domain, such as health, education, transportation, power grid etc., of the city to provide public services to citizens efficiently and ubiquitously. These expectations induce massive challenges and requirements. This research is aimed to highlight key ICT (Information and Communication Technology) challenges related to adaptation of smart city. Realizing the significance of effective data collection, storage, retrieval, and efficient network resource provisioning, the research proposes a high level architecture for smart city. The proposed framework is based on a hierarchical model of data storage and defines how different stakeholders will be communicating and offering services to citizens. The architecture facilitates step by step implementation towards a smart city, integrating services, as they are developed in a timely manner.

Efficient and dependable overlay networks

We describe QoSMap, a novel approach for mapping overlay networks with stringent QoS requirements. QoSMap computes high quality overlay paths by utilizing direct underlay paths that fulfill the applications topology and link-specific QoS requirements. It also improves application dependability by increasing resiliency against QoS failures under dynamic network conditions. The increased resiliency is achieved through the use of supplemental indirect paths which have a single intermediate node and which also meet application QoS requirements. For evaluation, we compared QoSMap with a simple QoS approach for overlay mapping. We compared the two approaches for fulfilling varying application requests with strict QoS requirements of latency and packet loss on PlanetLab. We observed that QoSMap yielded high quality overlays. Further, the use of indirect paths upon the QoS failure of the direct path avoided overlay reconfiguration and resulted in increased dependability and longer lifetime for the application overlays.

Clicksafe: Providing Security against Clickjacking Attacks

Click jacking is an act of hijacking user clicks in order to perform undesired actions which are beneficial for the attacker. We propose Click safe, a browser-based tool to provide increased security and reliability against click jacking attacks. Click safe is based on three major components. The detection unit detects malicious components in a web page that redirect users to external links. The mitigation unit provides interception of user clicks and give educated warnings to users who can then choose to continue or not. Click safe also incorporate a feedback unit which records the users actions, converts them into ratings and allows future interactions to be more informed. Click safe is predominant from other similar tools as the detection and mitigation is based on a comprehensive framework which utilizes detection of malicious web components and incorporating user feedback. We explain the mechanism of click safe, describes its performance, and highlights its potential in providing safety against click jacking to a large number of users.

Foundations of a generic design for complex event processing

Complex Event Processing (CEP) relates individual events to infer situations, detect threats, and analyze occurrences. In CEP analysis, the design constitutes prime significance, as it identifies events and builds correlation among them. In this research, we are motivated by the need of building efficient design for CEP systems. We focus on achieving a generic model as it builds foundation of real-time CEP analysis for a variety of applications. A major limitation in contemporary CEP systems is that they are confined to relating individual events and detecting a situation. Motivated by this limitation, we introduce the concept of Situation Analysis which would enhance the scope of CEP systems. Our design, including CEP system and situation analyzer, constitutes a basic paradigm for a generic complex event processing system. We present a detailed description of our design and layout an enhanced model which is useful for a variety of applications.

SyncProbe: Providing Assurance of Message Latency through Predictive Monitoring of Internet Paths

SyncProbe improves the end-to-end predictability of distributed systems by providing applications with a real-time estimate of the maximum expected message delay (upper bound on communication latency) for network paths. The upper bound is adjusted over time in response to the monitored network latency and serves as a real-time assurance of synchrony. We deployed SyncProbe on PlanetLab and assessed its performance with respect to violations, duration of synchrony, upper bound cost and recoverability. Experiments revealed that SyncProbe is successful in providing upper bound estimate in real-time for a variety of paths. The estimated upper bound can be utilized for more formal assessment of information related to timeouts, ordering of events or knowledge about global states. We describe the design and methodology of SyncProbe and discuss various issues related to its performance.

Interventions in Cyberspace: Status and Trends

Cyberinterventions such as attacks and exploitations could have a severe impact on peoples everyday activities. In this context, we must understand the dimensions and scope of attacks in cyberspace and assess measures to enhance the security of cybersystems. A global scenario should be considered given that entities could involve individuals, organizations, and state-sponsored actors.