Rasib Khan

OTIT: towards secure provenance modeling for location proofs

Personal mobile devices and location based services are gaining popularity every day. Since the location based services are often customized based on the location information, it is important to securely generate, preserve, and validate the claim of presence at a given location at a given time as well as location provenance - the history of locations for a mobile device user over a given time period. Location provenance needs to imply secure and chronological ordering of location proofs, which can be successfully verified at a later time. Otherwise, the location based services can be easily spoofed by falsified location history. In this paper, we present OTIT - a model for designing secure location provenance. We formalized the features and characteristics for the domain of secure location provenance schemes, using formal propositional logic and logical proofs. We also present several schemes, which can be used in various modes to provide secure location provenance services. Based on the characteristics defined in OTIT, we have analyzed different schemes to show their adherence to the desired features of secure location provenance. Furthermore, we present experimental results on the performance of the various schemes, in terms of time and storage, to show a comparative applicability analysis. We posit that OTIT will serve as a comprehensive benchmark framework to evaluate the models for secure location provenance.

'Who, When, and Where?' Location Proof Assertion for Mobile Devices

In recent years, location of mobile devices has become an important factor. Mobile device users can easily access various customized applications from the service providers based on the current physical location information. Nonetheless, it is a significant challenge in distributed architectures for users to prove their presence at a particular location in a privacy-protected and secured manner. So far, researchers have proposed multiple schemes to implement a secure location proof collection mechanism. However, such location proof schemes are subject to tampering and not resistant to collusion attacks. Additionally, the location authority providing a location proof is assumed to be honest at all times. In this paper, we present the fundamental requirements of any location proof generation scheme, and illustrate the potential attacks possible in such non-federated environments. Based on our observations, we introduce a concept of witness oriented endorsements, and describe a collusion-resistant protocol for asserted location proofs.We provide an exhaustive security analysis of the proposed architecture, based on all possible collusion models among the user, location authority, and witness. We also present a prototype implementation and extensive experimental results to adjust different threshold values and illustrate the feasibility of deploying the protocol in regular devices for practical use.

SEPIA: Secure-PIN-Authentication-as-a-Service for ATM Using Mobile and Wearable Devices

Credit card fraud is a common problem in todays world. Financial institutions have registered major loses till today due to users being exposed of their credit card information. Shoulder-surfing or observation attacks, including card skimming and video recording with hidden cameras while users perform PIN-based authentication at ATM terminals is one of the common threats for common users. Researchers have struggled to come up with secure solutions for secure PIN authentication. However, modern day ubiquitous wearable devices, such as the Google Glass have presented us with newer opportunities in this research area. In this paper, we propose Secure-PIN-Authentication-as-a-Service (SEPIA), a secure obfuscated PIN authentication protocol for ATM and other point-of-service terminals using cloud-connected personal mobile and wearable devices. Our approach protects the user from shoulder-surfers and partial observation attacks, and is also resistant to relay, replay, and intermediate transaction attacks. A SEPIA user utilizes a Google Glass or a mobile device for scanning a QR code on the terminal screen to prove co-location to the cloud-based server and obtain a secure PIN template for point-of-service authentication. SEPIA ensures minimal task overhead on the users device with maximal computation offloaded to the cloud. We have implemented a proof-of-concept prototype to perform experimental analysis and a usability study for the SEPIA architecture.

Interaction provenance model for unified authentication factors in service oriented computing

Authentication is one of the most fundamental security problems. To date, various distinct authentication factors such as passwords, tokens, certificates, and biometrics have been designed for authentication. In this paper, we propose using the history or provenance of previous interactions and events as the generic platform for all authentication challenges. In this paradigm, provenance of past interactions with the authenticating principle or a third party is used to authenticate a user. We show that the interaction provenance paradigm is generic and can be used to represent existing authentication factors, yet allow the use of newer methods. We also discuss how authentication based on interactions can allow very flexible but complex authentication and access control policies that are not easily possible with current authentication models.

A Cloud You Can Wear: Towards a Mobile and Wearable Personal Cloud

Mobile and wearable devices provide the expected user experience and the ability to run complex applications using cloud based services. This makes the design of such wearable devices complex, expensive, and with major data privacy concerns. In this paper, we present the concept of a wearable cloud -- a complete yet compact and lightweight cloud which can be embedded into the clothing of a user. The wearable cloud makes the design of mobile and wearable devices simple, inexpensive, and lightweight, tapping into the resources of the wearable cloud. We introduce five wearable cloud service delivery models including a prototype implementation of the wearable cloud and a cheap touchscreen terminal device. The paper presents experimental results on the usability of the wearable cloud based on energy consumption and application performance.

Fuzzy Authentication Using Interaction Provenance in Service Oriented Computing

In service oriented computing, authentication factors have their vulnerabilities when considered exclusively. Cross-platform and service composition architectures require a complex integration procedure and limit adoptability of newer authentication models. Authentication is generally based on a binary success or failure and relies on credentials proffered at the present moment without considering how or when the credentials were obtained by the subject. The resulting access control engines suffer from rigid service policies and complexity of management. In contrast, social authentication is based on the nature, quality, and length of previous encounters with each other. We posit that human-to-machine authentication is a similar causal effect of an earlier interaction with the verifying party. We use this notion to propose interaction provenance as the only unified representation model for all authentication factors in service oriented computing. Interaction provenance uses the causal relationship of past events to leverage service composition, cross-platform integration, timeline authentication, and easier adoption of newer methods. We extend our model with fuzzy authentication using past interactions and linguistic policies. The paper presents an interaction provenance recording and authentication protocol and a proof-of-concept implementation with extensive experimental evaluation.

Secure Cloud Connectivity for Scientific Applications

Cloud computing improves utilization and flexibility in allocating computing resources while reducing the infrastructural costs. However, in many cases cloud technology is still proprietary and tainted by security issues rooted in the multi-user and hybrid cloud environment. A lack of secure connectivity in a hybrid cloud environment hinders the adaptation of clouds by scientific communities that require scaling-out of the local infrastructure using publicly available resources for large-scale experiments. In this article, we present a case study of the DII-HEP secure cloud infrastructure and propose an approach to securely scale-out a private cloud deployment to public clouds in order to support hybrid cloud scenarios. A challenge in such scenarios is that cloud vendors may offer varying and possibly incompatible ways to isolate and interconnect virtual machines located in different cloud networks. Our approach is tenant driven in the sense that the tenant provides its connectivity mechanism. We provide a qualitative and quantitative analysis of a number of alternatives to solve this problem. We have chosen one of the standardized alternatives, Host Identity Protocol, for further experimentation in a production system because it supports legacy applications in a topologically-independent and secure way.

MIDEP: Multiparty Identity Establishment Protocol for Decentralized Collaborative Services

Decentralized collaborative architectures are gaining popularity in all application areas, varying from peer-to-peer communication and content management to cloud and ubiquitous services. However, the public identity of the user is still a major concern, in terms of privacy, trace ability, verifiability, masquerading, and other attacks in such environments. We demonstrate two new attacks, identity shadowing and the Man-in-the-Loop (MITL) attacks, which are applicable in particular to multiparty collaborative environments. In this paper, we propose MIDEP, a Multiparty Identity Establishment Protocol for collaborative environments. The proposed protocol allows a client to establish a secure, multiparty, probabilistic, temporal, verifiable, and non-traceable public identity with the collaborating peers in a decentralized architecture. MIDEP allows a client to avoid identity shadowing and protects the service from the resulting threats as well as from colluded information sharing among the collaborating peers. We illustrate how existing collaborative service frameworks can utilize MIDEP to securely establish the public identity prior to beginning the service session. A prototype implementation is utilized to perform extensive experimental analysis. Our results show that MIDEP is highly suitable in terms of overhead to ensure secure identity establishment for underlying decentralized collaborative services.

Accountable proof of ownership for data using timing element in cloud services

While many cloud storage and infrastructure systems exist today, none of them provide a mechanism for accountability of stored or user generated content. This lack of security support has been a major hurdle for auditing documents, claiming data possession, and proof of authorship. In this paper, we present a novel idea for secure accountability of timing element for data in massively scalable systems. The proposed scheme allows a service provider to incorporate timing accountability of data generated at the provider, by requesting proofs from accountability servers in the cloud. Additionally, the size of the proof is independent of the data size and is a unique feature of our system design. The scalability of the system have been evaluated using the Amazon EC2.

Litigo: A Cost-Driven Model for Opaque Cloud Services

Cloud computing provides software, platform, and infrastructure as a service that helps organizations to perform several resource intensive tasks. The services offered by a cloud service provider are limited by provider-specific options in terms of the pre-specified configurations. Moreover, it is sometimes expensive to pay a fixed amount of money without any format of negotiation or price-matching deals for the cloud-based services and resources. Conversely, the negotiator-based model for opaque services has gained popularity in various markets, such as, for flights, hotels, and rentals. We posit that a similar opaque inventory for cloud-based services and resources is the next generation niche for consumer acquisition and service delivery in the cloud computing market. Such a model will facilitate the clients with flexible resource and service provisioning at reasonable prices, and will also allow a higher revenue and increase resource utilization for cloud service providers. In this paper, we propose Litigo, a cost-driven model for opaque service platforms for cloud computing. The Litigo component acts as a middle-man to deliver cloud-based services from a set of cloud service providers to the end users. We present a detailed cost model and comparison between establishing a cloud service vs. an opaque cloud service. Our empirical framework allows a Litigo service provider to analyze the profit model and creates the market niche accordingly. We performed extensive analysis using simulated model verification for Litigo. The proposed model delivers an opaque cloud as a service to clients at a reasonable price by maximizing the resource utilization and revenue of cloud service providers.