Datacenters are witnessing an increasing trend in adopting microservice-based architecture for application design, which consists of a combination of different microservices. Typically these applications are short-lived and are administered with strict Service Level Objective (SLO) requirements. Traditional virtual machine (VM) based provisioning for such applications not only suffers from long latency when provisioning resources (as VMs tend to take a few minutes to start up), but also places an additional overhead of server management and provisioning on the users. This led to the adoption of serverless functions, where applications are composed as functions and hosted in containers. However, state-of-the-art schedulers employed in serverless platforms tend to look at microservice-based applications similar to conventional monolithic black-box applications. To detect all the inefficiencies, we characterize the end-to-end life cycle of these microservice-based applications in this work. Our findings show that the applications suffer from poor scheduling of microservices due to reactive container provisioning during workload fluctuations, thereby resulting in either in SLO violations or colossal container over-provisioning, in turn leading to poor resource utilization. We also find that there is an ample amount of slack available at each stage of application execution, which can potentially be leveraged to improve the overall application performance.

The microservice architecture has dramatically reduced user effort in adopting and maintaining servers by providing a catalog of functions as services that can be used as building blocks to construct applications. This has enabled datacenter operators to look at managing datacenter hosting microservices quite differently from traditional infrastructures. Such a paradigm shift calls for a need to rethink resource management strategies employed in such execution environments. We observe that the visibility enabled by a microservices execution framework can be exploited to achieve high throughput and resource utilization while still meeting Service Level Agreements, especially in multi-tenant execution scenarios.

We introduce Caliper , a technique for accurately estimating performance interference occurring in shared servers. Caliper overcomes the limitations of prior approaches by leveraging a micro-experiment-based technique. In contrast to state-of-the-art approaches that focus on periodically pausing co-running applications to estimate slowdown, Caliper utilizes a strategic phase-triggered technique to capture interference due to co-location. This enables Caliper to orchestrate an accurate and low-overhead interference estimation technique that can be readily deployed in existing production systems. We evaluate Caliper for a broad spectrum of workload scenarios, demonstrating its ability to seamlessly support up to 16 applications running simultaneously and outperform the state-of-the-art approaches.

Cloud-scale datacenter management systems utilize virtualization to provide performance isolation while maximizing the utilization of the underlying hardware infrastructure. However, virtualization does not provide complete performance isolation as Virtual Machines (VMs) still compete for nonreservable shared resources (like caches, network, I/O bandwidth etc.) This becomes highly challenging to address in datacenter environments housing tens of thousands of VMs, causing degradation in application performance. Addressing this problem for production datacenters requires a non-intrusive scalable solution that 1) detects performance intrusion and 2) investigates both the intrusive VMs causing interference, as well as the resource(s) for which the VMs are competing for. To address this problem, this paper introduces Proctor, a real time, lightweight and scalable analytics fabric that detects performance intrusive VMs and identifies its root causes from among the arbitrary VMs running in shared datacenters across 4 key hardware resources - network, I/O, cache, and CPU. Proctor is based on a robust statistical approach that requires no special profiling phases, standing in stark contrast to a wide body of prior work that assumes pre-acquisition of application level information prior to its execution. By detecting performance degradation and identifying the root cause VMs and their metrics, Proctor can be utilized to dramatically improve the performance outcomes of applications executing in large-scale datacenters. From our experiments, we are able to show that when we deploy Proctor in a datacenter housing a mix of I/O, network, compute and cache-sensitive applications, it is able to effectively pinpoint performance intrusive VMs. Further, we observe that when Proctor is applied with migration, the application-level Quality-of-Service improves by an average of 2.2× as compared to systems which are unable to detect, identify and pinpoint performance intrusion and their root causes.

Guaranteeing Quality-of-Service (QoS) of latency-sensitive applications while improving server utilization through application co-location is important yet challenging in modern datacenters. The key challenge is that when applications are co-located on a server, performance interference due to resource contention can be detrimental to the application QoS. Although prior work has proposed techniques to identify "safe" co-locations where application QoS is satisfied by predicting the performance interference on multicores, no such prediction technique on accelerators such as GPUs.

Web Applications form an integral part of our day to day life. The number of attacks on websites and the compromise of many individuals' secure data are increasing at an alarming rate. With the advent of social networking and e-commerce, web security attacks such as phishing and spamming have become quite common. The consequences of these attacks are ruthless. Hence, providing increased amount of security for the users and their data becomes essential. Most important vulnerability as described in top 10 web security issues by Open Web Application Security Project is SQL Injection Attack(SQLIA) [3]. This paper focuses on how the advantages of randomization can be employed to prevent SQL injection attacks in web based applications. SQL injection can be used for unauthorized access to a database to penetrate the application illegally, modify the database or even remove it. For a hacker to modify a database, details such as field and table names are required. So we try to propose a solution to the above problem by preventing it using an encryption algorithm based on randomization. It has better performance and provides increased security in comparison to the existing solutions. Also the time to crack the database takes more time when techniques such as dictionary and brute force attack are deployed. Our main aim is to provide increased security by developing a tool which prevents illegal access to the database.