Designing and optimization of VOIP PBX infrastructure

In the recent decade, communication has stirred from the old wired medium such as public switched telephone network (PSTN) to the Internet. Present, Voice over Internet Protocol (VoIP) Technology used for communication on internet by means of packet switching technique. Several years ago, an internet protocol (IP) based organism was launched, which is known as Private Branch Exchange "PBX", as a substitute of common PSTN systems. For free communication, probably you must have to be pleased with starting of domestic calls. Although, fairly in few cases, VoIP services can considerably condense our periodical phone bills. For instance, if someone makes frequent global phone calls, VoIP talk service is the actual savings treat which cannot achieve by using regular switched phone. VoIP talk services strength help to trim down your phone bills if you deal with a lot of long-distance (international) and as well as domestic phone calls. However, with the VoIP success, threats and challenges also stay behind. In this dissertation, by penetration testing one will know that how to find network vulnerabilities how to attack them to exploit the network for unhealthy activities and also will know about some security techniques to secure a network. And the results will be achieved by penetration testing will indicate of proven of artefact and would be helpful to enhance the level of network security to build a more secure network in future

SECURING USER INTERACTION CHANNELS ON MOBILE PLATFORM USING ARM TRUSTZONE

Smartphones have become an essential part of our lives, and are used daily forimportant tasks like banking, shopping, and making phone calls. Smartphones provide several interaction channels which can be affected by a compromised mobile OS. This dissertation focuses on the user interaction channels of UI input and audio I/O. The security of the software running on smartphones has become more critical because of widespread smartphone usage. A technology called TEE (Trusted Execution Environment) has been introduced to help protect users in the event of OS compromise, with the most commonly deployed TEE on mobile devices being ARM TrustZone. This dissertation utilizes ARM TrustZone to provide secure design for user interactionchannels of UI input (called Truz-UI) and Audio I/O for VoIP calls (called Truz-Call). The primary goal is to ensure that the design is transparent to mobile applications. During research based on TEE, one of the important challenges that is encountered is the ability to prototype a secure design. In TEE research one often needs to interface hardware peripherals with the TEE OS, which can be challenging for non-hardware experts, depending on the available support from the TEE OS vendor. This dissertation discusses a simulation based approach (called Truz-Sim) that reduces setup time and hardware experience required to build a hardware environment for TEE prototyping

Efficient Resource Management Mechanism for 802.16 Wireless Networks Based on Weighted Fair Queuing

Wireless Networking continues on its path of being one of the most commonly used means of communication. The evolution of this technology has taken place through the design of various protocols. Some common wireless protocols are the WLAN, 802.16 or WiMAX, and the emerging 802.20, which specializes in high speed vehicular networks, taking the concept from 802.16 to higher levels of performance. As with any large network, congestion becomes an important issue. Congestion gains importance as more hosts join a wireless network. In most cases, congestion is caused by the lack of an efficient mechanism to deal with exponential increases in host devices. This can effectively lead to very huge bottlenecks in the network causing slow sluggish performance, which may eventually reduce the speed of the network. With continuous advancement being the trend in this technology, the proposal of an efficient scheme for wireless resource allocation is an important solution to the problem of congestion. The primary area of focus will be the emerging standard for wireless networks, the 802.16 or “WiMAX”. This project, attempts to propose a mechanism for an effective resource management mechanism between subscriber stations and the corresponding base station

Voice over Internet Protocol (VOIP): Overview, Direction And Challenges

Voice will remain a fundamental communication media that cuts across people of all walks of life. It is therefore important to make it cheap and affordable. To be reliable and affordable over the common Public Switched Telephone Network, change is therefore inevitable to keep abreast with the global technological change. It is on this basis that this paper tends to critically review this new technology VoIP, x-raying the different types. It further more discusses in detail the VoIP system, VoIP protocols, and a comparison of different VoIP protocols. The compression algorithm used to save network bandwidth in VoIP, advantages of VoIP and problems associated with VoIP implementation were also critically examined. It equally discussed the trend in VoIP security and Quality of Service challenges. It concludes by reiterating the need for a cheap, reliable and affordable means of communication that would not only maximize cost but keep abreast with the global technological change. Keywords: Voice over Internet Protocol (VoIP), Public Switched Telephone Network (PSTN), Session Initiation Protocol (SIP),  multipoint control uni

Interworking Architectures in Heterogeneous Wireless Networks: An Algorithmic Overview

The scarce availability of spectrum and the proliferation of smartphones, social networking applications, online gaming etc., mobile network operators (MNOs) are faced with an exponential growth in packet switched data requirements on their networks. Haven invested in legacy systems (such as HSPA, WCDMA, WiMAX, Cdma2000, LTE, etc.) that have hitherto withstood the current and imminent data usage demand, future and projected usage surpass the capabilities of the evolution of these individual technologies. Hence, a more critical, cost-effective and flexible approach to provide ubiquitous coverage for the user using available spectrum is of high demand. Heterogeneous Networks make use of these legacy systems by allowing users to connect to the best network available and most importantly seamlessly handover active sessions amidst them. This paper presents a survey of interworking architectures between IMT 2000 candidate networks that employ the use of IEFT protocols such as MIP, mSCTP, HIP, MOBIKE, IKEV2 and SIP etc. to bring about this much needed capacity