Venkatesh Krishnaswamy

Location Privacy Enforcement in a Location-Based Services Platform

Location privacy management is an important requirement for location based services. Here we describe the design and implementation of location privacy enforcement mechanisms based on the IETF Geopriv specifications as part a location-based services platform that we previously developed. Our design involves a new and more efficient session-based access validation mechanism. In addition, we evaluate the expressiveness of Geopriv rules for describing a variety of privacy rules. We find a number of limitations and propose some methods for extending the rule notation for addressing these limitations. We conclude with an overview of our prototype implementation.

Building Communicating Web Applications Leveraging Endpoints and Cloud Resource Service

We describe a resource-based architecture to quickly and easily build communicating web applications. Resources are structured and hierarchical data stored in the server but accessed by the endpoint via the application logic running in the browser. The architecture enables deployments that are fully cloud based, fully on-premise or hybrid of the two. Unlike a single web application controlling the users social data, this model allows any application to access the authenticated users resources for application mash-ups, e.g., user contacts created by one application are used by another on permission from the user instead of the first application. We present a Rtisy, a platform to further simplify web application development by using pre-built communication widgets for common use cases such as phone call, conferencing, call distribution and video publish or play. The architecture extends beyond web to native applications and reduces the barrier between web and non-web applications for communication. Our resource access protocol acts as a generic signaling mechanism for the emerging WebRTC (Web Real-Time Communications). We have implemented several applications completely in HTML5 running in the browser using this resource-based architecture.

Enhancing Application-Layer Multicast for P2P Conferencing

While application-layer multicast (ALM) can re- duce latency and permit deployment in networks without network-layer multicast, often, it does not leverage application- specific behavior. For example, the existing ALM-based peer-to- peer (P2P) conferencing systems route media packets based only on bandwidth and on transmission delay without considering P2P conferencing specific behavior and varying mixing capabilities of participating peers. We propose an enhanced hybrid ALM-based P2P conferencing architecture that can leverage participating peers with different capabilities. We also present a three-step algorithm to construct such a hybrid ALM-based P2P conference. We have built a prototype for our architecture. Results from our prototype show that our approach is more scalable than the existing ALM-based P2P conferencing systems.

A case for SIP in Javascript

This article presents the challenges and compares the alternatives to interoperate between SIP-based systems and the emerging standards for web real-time communication (WebRTC). We argue for an endpoint- and web-focused architecture, and present both sides of the SIP in JavaScript approach. Until WebRTC has ubiquitous cross-browser availability, we suggest a fallback strategy for web developer: detect and use HTML5 if available; otherwise, fall back to a browser plugin.

Virtual Worlds as a Tool for Enterprise Services

Online virtual worlds offer exciting new opportunities for enterprises or businesses. To exploit these opportunities enterprises need to find a way to integrate virtual world services with their real-world services, and to exploit virtual worlds rich collaboration environment to offer new or enhanced services. However, there are many challenges to realizing these goals, such as resolving virtual and real identifications, controlling communication sessions between real and virtual world entities, and managing resources in both worlds. In this paper, we study these issues and propose a framework for integrating virtual worlds into enterprise service work flow. We implemented a customer service in a VW contact center that is integrated with corresponding enterprise services. We also present a novel mechanism in virtual worlds that allow users to bring their own resources, along with the contact center resources, and share the resources with other customers or agents to resolve customer issues. Further, we present experiences from our prototype.

Dynamic peer-to-peer overlays for voice systems

Different devices, such as mobile phones, soft phones, or desktop phones, have varying processing power, bandwidth, and media capabilities. Heterogeneous P2P voice systems that are built based on a set of capabilities will not be suitable for devices that have different capabilities. In this paper, we present an architecture for P2P voice systems that can dynamically change P2P overlay mechanisms to better suit different device, user, and feature requirements of a P2P voice system. As a first step towards realizing the architecture, we propose a P2P-SIP based architecture that separates out P2P mechanisms from SIP. Our architecture allows dynamic P2P structural changes, limits bloating of the SIP protocol, and lays a foundation for a flexible hierarchical system

Federated enterprise and cloud-based collaboration services

Because of the variety of types of collaboration services used in enterprises today, there is difficulty in integrating related work threads from different collaboration environments. Each collaboration tool differs in storage model, APIs, content organization, content addressing, content formats, user authentication, and user interface. Nevertheless users prefer to be able to choose which collaboration tool they use for a given interaction, and over the course of long-term collaboration, will typically use a variety of tools, including email, instant messages, wikis, blogs, web conferences, and shared documents. The solution presented here is to provide a federated integration of these different collaboration tools to make content access and transfer straight forward between different systems. Additionally, we enable the user to achieve this federation by working directly in the client application of their choice; we illustrate this with plug-ins for MS Outlook, Internet Explorer and Skype. Our architecture integrates both desktop and server-centric tools. Additionally it is now possible to use hosted collaboration services in the cloud. This further complicates the ability to federate collaboration tools because of requirements to protect enterprise information and information flows. We present an architecture to address the federation of cloud-based collaboration services.

Reconsidering Social Networks for Enterprise Communication Services

Social networking applications leverage valuable information from social graphs and integrate communication capabilities to offer new services. However, currently, these applications are limited to communication capabilities such as click-to-call or click-to-conference. Once the communication session is established the social context and the communication context are not integrated in these services. For social network communication services such integration permits new and novel user services. Further, enabling those services in the enterprise context will enhance social networks as a communication and collaboration tool in enterprises. In this paper, we look at such services and argue that social network applications and enterprise social networking communication applications have some fundamental differences. We discuss new notions such as transient relationships, domain separation, user views, and several other issues that need to be addressed for enabling new social networking communication services for enterprises. We present a model that addresses these issues and describe our prototype implementation with a use case example.

Managing Distributed Feature Interactions in Enterprise SIP Application Servers

Several trends in SIP application server deployments in large scale telephony environments exacerbate the classic problem of feature interaction : use of distributed feature servers, mixing of legacy and green-field feature servers, and the co-existence of multiple third-party feature implementations provisioned in the same environment. Next-generation SIP application servers will include an application router (AR) to provide more application control over feature sequencing. As we discuss here, the AR can be augmented to incorporate feature interaction detection and resolution logic. We describe a novel design for run-time feature interaction detection and resolution in an environment of distributed feature servers using a SIP application server with application routing function, such as that defined in JSR 289. The approach is based on the algorithm of the Kolberg-Magill (K-M) method for feature interaction detection. Here we extend the notation of the algorithm to cover advanced call control services, enable the algorithm to work in topologies involving B2BUAs (Back-to-Back User Agents) and SBCs (Session Border Controllers), and test the approach with a substantial feature set of 32 features found in large enterprise solutions.

Integrating Enterprise Communications into Google Wave

This paper proposes our approach of integrating enterprise telecommunication functions into Google Wave. Our approach can monitor communication events and utilize Google Wave functions to enhance call handling.