Study of TCP Issues over Wireless and Implementation of iSCSI over Wireless for Storage Area Networks

The Transmission Control Protocol (TCP) has proved to be proficient in classical wired networks, presenting an ability to acclimatize to modern, high-speed networks and present new scenarios for which it was not formerly designed. Wireless access to the Internet requires that information reliability be reserved while data is transmitted over the radio channel. Automatic repeat request (ARQ) schemes and TCP techniques are often used for error-control at the link layer and at the transport layer, respectively. TCP/IP is becoming a communication standard [1]. Initially it was designed to present reliable transmission over IP protocol operating principally in wired networks. Wireless networks are becoming more ubiquitous and we have witnessed an exceptional growth in heterogeneous networks. This report considers the problem of supporting TCP, the Internet data transport protocol, over a lossy wireless link whose features vary over time. Experimental results from a wireless test bed in a research laboratory are reported

SDN Enabled Network Efficient Data Regeneration for Distributed Storage Systems

Distributed Storage Systems (DSSs) have seen increasing levels of deployment in data centers and in cloud storage networks. DSS provides efficient and cost-effective ways to store large amount of data. To ensure reliability and resilience to failures, DSS employ mirroring and coding schemes at the block and file level. While mirroring techniques provide an efficient way to recover lost data, they do not utilize disk space efficiently, resulting in large overheads in terms of data storage. Coding techniques on the other hand provide a better way to recover data as they reduce the amount of storage space required for data recovery purposes. However, the current recovery process for coded data is not efficient due to the need to transfer large amounts of data to regenerate the data lost as a result of a failure. This results in significant delays and excessive network traffic resulting in a major performance bottleneck. In this thesis, we propose a new architecture for efficient data regeneration in distribution storage systems. A key idea of our architecture is to enable network switches to perform network coding operations, i.e., combine packets they receive over incoming links and forward the resulting packet towards the destination and do this in a principled manner. Another key element of our framework is a transport-layer reverse multicast protocol that takes advantage of network coding to minimize the rebuild time required to transmit the data by allowing more efficient utilization of network bandwidth. The new architecture is supported using the principles of Software Defined Networking (SDN) and making extensions where required in a principled manner. To enable the switches to perform network coding operations, we propose an extension of packet processing pipeline in the dataplane of a software switch. Our testbed experiments show that the proposed architecture results in modest performance gains

Hyperscsi : Design and development of a new protocol for storage networking

Ph.DDOCTOR OF PHILOSOPH

Performance analysis and design of iSCSI over wireless network

Master'sMASTER OF ENGINEERIN

High availability using virtualization

High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows to share the running virtual machines over the servers up and running, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The system (3RC) is based on a finite state machine with hysteresis, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system. As extension of the 3RC architecture, several storage solutions have been tested to store and centralize all the virtual disks, from NAS to SAN, to grant data safety and access from everywhere. Exploiting virtualization and ability to automatically reinstall a host, we provide a sort of host on-demand, where the action on a virtual machine is performed only when a disaster occurs.Comment: PhD Thesis in Information Technology Engineering: Electronics, Computer Science, Telecommunications, pp. 94, University of Pisa [Italy

Deleting Collected Digital Evidence by Exploiting a Widely Adopted Hardware Write Blocker

In this primary work we call for the importance of integrating security testing into the process of testing digital forensic tools. We postulate that digital forensic tools are increasing in features (such as network imaging), becoming networkable, and are being proposed as forensic cloud services. This raises the need for testing the security of these tools, especially since digital evidence integrity is of paramount importance. At the time of conducting this work, little to no published anti-forensic research had focused on attacks against the forensic tools/process.We used the TD3, a popular, validated, touch screen disk duplicator and hardware write blocker with networking capabilities and designed an attack that corrupted the integrity of the destination drive (drive with the duplicated evidence) without the user\u27s knowledge. By also modifying and repackaging the firmware update, we illustrated that a potential adversary is capable of leveraging a phishing attack scenario in order to fake digital forensic practitioners into updating the device with a malicious operating system. The same attack scenario may also be practiced by a disgruntled insider. The results also raise the question of whether security standards should be drafted and adopted by digital forensic tool makers

SDN Enabled Network Efficient Data Regeneration for Distributed Storage Systems

Distributed Storage Systems (DSSs) have seen increasing levels of deployment in data centers and in cloud storage networks. DSS provides efficient and cost-effective ways to store large amount of data. To ensure reliability and resilience to failures, DSS employ mirroring and coding schemes at the block and file level. While mirroring techniques provide an efficient way to recover lost data, they do not utilize disk space efficiently, resulting in large overheads in terms of data storage. Coding techniques on the other hand provide a better way to recover data as they reduce the amount of storage space required for data recovery purposes. However, the current recovery process for coded data is not efficient due to the need to transfer large amounts of data to regenerate the data lost as a result of a failure. This results in significant delays and excessive network traffic resulting in a major performance bottleneck. In this thesis, we propose a new architecture for efficient data regeneration in distribution storage systems. A key idea of our architecture is to enable network switches to perform network coding operations, i.e., combine packets they receive over incoming links and forward the resulting packet towards the destination and do this in a principled manner. Another key element of our framework is a transport-layer reverse multicast protocol that takes advantage of network coding to minimize the rebuild time required to transmit the data by allowing more efficient utilization of network bandwidth. The new architecture is supported using the principles of Software Defined Networking (SDN) and making extensions where required in a principled manner. To enable the switches to perform network coding operations, we propose an extension of packet processing pipeline in the dataplane of a software switch. Our testbed experiments show that the proposed architecture results in modest performance gains

Benchmarking of IP-based Network Storage Systems

Mobile platforms with access to high speed wireless network have become ubiquitous. Advancements in network technology and consumer electronics have brought traditional storage systems into offices and homes. Services based on cloud technologies, including object based storage, have gained popularity among both private users and enterprises. However, there is still a lack of systematic evaluation of both traditional storage systems and cloud based object storage in a mobile and wireless context. In this thesis, we evaluate the performance of three drastically different storage systems, namely NFS, iSCSI, and OpenStack Swift, which can potentially be used by mobile platforms over wireless network. We build a testbed and an in house, ad hoc microbenchmark to study the impact of various network complexities and different access behaviours of application. In addition, we employ two widely used macrobenchmarks -- PostMark and FileBench -- to simulate the workloads of typical applications. We find that: (1) iSCSI excels in networks whose condition is as good as LAN; (2) NFS and Swift are more suitable for complex networks such as wireless network and WAN; (3) Swift is a viable replacement for NFS in all scenarios; and (4) System configuration on the client side impacts storage performance significantly and deserve adequate attention. Furthermore, we make several recommendations to practitioners and point out numerous future research directions

SDN Enabled Network Efficient Data Regeneration for Distributed Storage Systems

Distributed Storage Systems (DSSs) have seen increasing levels of deployment in data centers and in cloud storage networks. DSS provides efficient and cost-effective ways to store large amount of data. To ensure reliability and resilience to failures, DSS employ mirroring and coding schemes at the block and file level. While mirroring techniques provide an efficient way to recover lost data, they do not utilize disk space efficiently, resulting in large overheads in terms of data storage. Coding techniques on the other hand provide a better way to recover data as they reduce the amount of storage space required for data recovery purposes. However, the current recovery process for coded data is not efficient due to the need to transfer large amounts of data to regenerate the data lost as a result of a failure. This results in significant delays and excessive network traffic resulting in a major performance bottleneck. In this thesis, we propose a new architecture for efficient data regeneration in distribution storage systems. A key idea of our architecture is to enable network switches to perform network coding operations, i.e., combine packets they receive over incoming links and forward the resulting packet towards the destination and do this in a principled manner. Another key element of our framework is a transport-layer reverse multicast protocol that takes advantage of network coding to minimize the rebuild time required to transmit the data by allowing more efficient utilization of network bandwidth. The new architecture is supported using the principles of Software Defined Networking (SDN) and making extensions where required in a principled manner. To enable the switches to perform network coding operations, we propose an extension of packet processing pipeline in the dataplane of a software switch. Our testbed experiments show that the proposed architecture results in modest performance gains