Using an External DHT as a SIP Location Service

Peer-to-peer Internet telephony using the Session Initiation Protocol (P2P-SIP) can exhibit two different architectures: an existing P2P network can be used as a replacement for lookup and updates, or a P2P algorithm can be implemented using SIP messages. In this paper, we explore the first architecture using the OpenDHT service as an externally managed P2P network. We provide design details such as encryption and signing using pseudo-code and examples to provide P2P-SIP for various deployment components such as P2P client, proxy and adaptor, based on our implementation. The design can be used with other distributed hash tables (DHTs) also

Securing VoIP: A Framework to Mitigate or Manage Risks

In Australia, the past few years have seen Voice over IP (VoIP) move from a niche communications medium used by organisations with the appropriate infrastructure and capabilities to a technology that is available to any one with a good broadband connection. Driven by low cost and no cost phone calls, easy to use VoIP clients and increasingly reliable connections, VoIP is replacing the Public Switch Telephone Network (PSTN) in a growing number of households. VoIP adoption appears to be following a similar path to early Internet adoption, namely little awareness by users of the security implications. Lack of concern about security by VoIP users is probably due to the relatively risk free service provided by the PSTN. However, VoIP applications use the Internet as their communications medium and therefore the risk profile is significantly different to the PSTN. This paper reviews the risks for two VoIP implementation models now being increasingly used in Australian homes; the PC softphone and the Analogue Telephony Adaptor (ATA). An overview of each of the VoIP implementation models is given together with a description of the respective technologies and protocols utilised. The VoIP security threats, applicable to the two VoIP implementation models considered, are enumerated and vulnerabilities that could be exploited are considered. Available security mechanisms that address the identified vulnerabilities are discussed. A practical and pragmatic VoIP security framework is proposed that will enable a user to mitigate or manage the risks associated with using the VoIP implementation models considered. By applying the VoIP security framework a user will be able to deploy a secure VoIP solution appropriate for residential use

Network Traffic Aware Smartphone Energy Savings

In today\u27s world of ubiquitous Smartphone use, extending the battery life has become an important issue. A significant contributor to battery drain is wireless networking. Common usage patterns expect Smartphones to maintain a constant Internet connection which exacerbates the problem.;Our research entitled A Network Traffic Approach to Smartphone Energy Savings focuses on extending Smartphone battery life by investigating how network traffic impacts power management of wireless devices. We explore 1) Real-time VoIP application energy savings by exploiting silence periods in conversation. WiFi is opportunistically placed into low power mode during Silence periods. 2.) The priority of Smartphone Application network traffic is used to modifiy WiFi radio power management using machine learning assisted prioritization. High priority network traffic is optimized for performance, consuming more energy while low priority network traffic is optimized for energy conservation. 3.) A hybrid multiple PHY, MAC layer approach to saving energy is also utilized. The Bluetooth assisted WiFi approach saves energy by combining high power, high throughput WiFi with low power, lower throughput Bluetooth. The switch between Bluetooth and WiFi is done opportunistically based upon the current data rate and health of the Bluetooth connection.;Our results show that application specific methods for wireless energy savings are very effective. We have demonstrated energy savings exceeding 50% in generic cases. With real-time VoIP applications we have shown upwards of 40% energy savings while maintaining good call quality. The hybrid multiple PHY approach saves more than 25% energy over existing solutions while attaining the capability of quickly adapting to changes in network traffic

Service composition based on SIP peer-to-peer networks

Today the telecommunication market is faced with the situation that customers are requesting for new telecommunication services, especially value added services. The concept of Next Generation Networks (NGN) seems to be a solution for this, so this concept finds its way into the telecommunication area. These customer expectations have emerged in the context of NGN and the associated migration of the telecommunication networks from traditional circuit-switched towards packet-switched networks. One fundamental aspect of the NGN concept is to outsource the intelligence of services from the switching plane onto separated Service Delivery Platforms using SIP (Session Initiation Protocol) to provide the required signalling functionality. Caused by this migration process towards NGN SIP has appeared as the major signalling protocol for IP (Internet Protocol) based NGN. This will lead in contrast to ISDN (Integrated Services Digital Network) and IN (Intelligent Network) to significantly lower dependences among the network and services and enables to implement new services much easier and faster. In addition, further concepts from the IT (Information Technology) namely SOA (Service-Oriented Architecture) have largely influenced the telecommunication sector forced by amalgamation of IT and telecommunications. The benefit of applying SOA in telecommunication services is the acceleration of service creation and delivery. Main features of the SOA are that services are reusable, discoverable combinable and independently accessible from any location. Integration of those features offers a broader flexibility and efficiency for varying demands on services. This thesis proposes a novel framework for service provisioning and composition in SIP-based peer-to-peer networks applying the principles of SOA. One key contribution of the framework is the approach to enable the provisioning and composition of services which is performed by applying SIP. Based on this, the framework provides a flexible and fast way to request the creation for composite services. Furthermore the framework enables to request and combine multimodal value-added services, which means that they are no longer limited regarding media types such as audio, video and text. The proposed framework has been validated by a prototype implementation

A novel mechanism for anonymizing Global System for Mobile Communications calls using a resource-based Session Initiation Protocol community network

Considering the widespread adoption of smartphones in mobile communications and the well-established resource sharing use in the networking community, we present a novel mechanism to achieve anonymity in the Global System for Mobile Communications (GSM). We propose a Voice over Internet Protocol infrastructure using the Session Initiation Protocol (SIP) where a smartphone registers on a SIP registrar and can start GSM conversation through another smartphone acting as a GSM gateway, by using a SIP intermediate without an extra cost. The testbed that we developed for empirical evaluation revealed no significant quality of service degradation

A Secure Peer-to-Peer Application Framework

The nature of the Internet has changed dramatically. From a modest research network, it has evolved into one of the most important fabrics of our modern society, affecting the lives of billions each day. We rely on it for everything from performing our daily chores to accessing rich media and keeping in touch with our friends. Despite this change, service provisioning has largely remained intact. Services are provided in a centralized manner, resulting in bottlenecks and vulnerable collections of, often unwittingly, submitted sensitive information. Peer-to-peer (P2P) technologies have the potential to provide a better alternative for future networking. P2P services distribute the load from a single node to a network of peers, relying on the resources of the end-users themselves. Not only does it remove the bottlenecks, it has the potential to provide a more personal and safe networking environment. In this dissertation, we inspect the feasibility and implications of a generic, cross-application, P2P framework. We present the design and implementation of a framework that uses existing infrastructure and advanced networking protocols to create a secure environment. Using this framework, applications are able to benefit from P2P networking without having to deploy new infrastructure or implement complex connection- and identity management. Users benefit from using a single, strong, cross-application identity management and having better control over their data. This improves the trust within the system and enables new ways of dealing with security threats. We demonstrate the feasibility of the framework by evaluating the performance and usability of the prototype implementation. This provides a model for future networking applications and insight into the security and usability issues these will face

Security for Decentralised Service Location - Exemplified with Real-Time Communication Session Establishment

Decentralised Service Location, i.e. finding an application communication endpoint based on a Distributed Hash Table (DHT), is a fairly new concept. The precise security implications of this approach have not been studied in detail. More importantly, a detailed analysis regarding the applicability of existing security solutions to this concept has not been conducted. In many cases existing client-server approaches to security may not be feasible. In addition, to understand the necessity for such an analysis, it is key to acknowledge that Decentralised Service Location has some unique security requirements compared to other P2P applications such as filesharing or live streaming. This thesis concerns the security challenges for Decentralised Service Location. The goals of our work are on the one hand to precisely understand the security requirements and research challenges for Decentralised Service Location, and on the other hand to develop and evaluate corresponding security mechanisms. The thesis is organised as follows. First, fundamentals are explained and the scope of the thesis is defined. Decentralised Service Location is defined and P2PSIP is explained technically as a prototypical example. Then, a security analysis for P2PSIP is presented. Based on this security analysis, security requirements for Decentralised Service Location and the corresponding research challenges -- i.e. security concerns not suitably mitigated by existing solutions -- are derived. Second, several decentralised solutions are presented and evaluated to tackle the security challenges for Decentralised Service Location. We present decentralised algorithms to enable availability of the DHTs lookup service in the presence of adversary nodes. These algorithms are evaluated via simulation and compared to analytical bounds. Further, a cryptographic approach based on self-certifying identities is illustrated and discussed. This approach enables decentralised integrity protection of location-bindings. Finally, a decentralised approach to assess unknown identities is introduced. The approach is based on a Web-of-Trust model. It is evaluated via prototypical implementation. Finally, the thesis closes with a summary of the main contributions and a discussion of open issues

Toward the PSTN/Internet Inter-Networking--Pre-PINT Implementations

This document contains the information relevant to the development of the inter-networking interfaces underway in the Public Switched Telephone Network (PSTN)/Internet Inter-Networking (PINT) Working Group. It addresses technologies, architectures, and several (but by no means all) existing pre-PINT implementations of the arrangements through which Internet applications can request and enrich PSTN telecommunications services. The common denominator of the enriched services (a.k.a. PINT services) is that they combine the Internet and PSTN services in such a way that the Internet is used for non-voice interactions, while the voice (and fax) are carried entirely over the PSTN. One key observation is that the pre-PINT implementations, being developed independently, do not inter-operate. It is a task of the PINT Working Group to define the inter-networking interfaces that will support inter-operation of the future implementations of PINT services

Telephony Calls over Bluetooth

VoIP is born from the growing Internet infrastructure, which has over the years seen significant improvements in both bandwidth and end-to-end latency. Merging VoIP technologies with telephony infrastructures is of particular interest since it significantly reduces the costs. In this project, we are making voice calls over Intranet available on a mobile phone using Bluetooth as the access protocol. Bluetooth was selected because it is increasingly available in mobile telephones. Most modern mobile phones with a focus on wirelessly sharing data between the device and a host PC come equipped with a Bluetooth adaptor. The project mainly consists of developing a Voiceover- Bluetooth (VoB) mobile application for Android phones and a PC application to enable voice calls over Intranet and Bluetooth connection. The mobile application connects to desktop application over BT to make and receive calls. The desktop application establish/receive call with/from other mobile/phone terminals over Intranet. When in range of a PC, a wireless Bluetooth connection to the IP network is made available to the mobile phone, offering the choice of connecting to a conventional mobile GSM network or to a lower-cost IP infrastructure. The vision for the future is to make the mobile phone2019;s operation fully transparent to the user by making both technologies completely interchangeable