DTMF and CLIP decoding in a noisy area using adaptive approach

Multi-frequency signals are greatly used in telecommunication fields. Signaling and speech are such an example of multi-frequency signals exchanging through the telecommunication networks. Extracting the frequencies embedded in these signals is very useful for a lot of operations: like filtering, decoding, compressing….We propose in this paper adaptive technique to process in real time multi-frequency signals and extracting the frequencies that they contain. Keywords: DTMF, CLIP, Noise, Adaptive, Real Tim

Error Probability in Redundant Packet Sending over IP Network

In this paper we calculate error probability of packetized signal when method of redundant packet sending is used in IP network. The number of repeated signaling packets from each interval of packetization is determined to achieve the desired error probability. The method for management of this number of repetitions is developed based on the new analysis. This method is especially important in the case of sending signaling criteria of classic telephony network over IP network, because it makes possible to reach the same error probability as in classic telephony network

Facsimile intrusion systems over IP networks

In this thesis, we investigate the security vulnerabilities present in sending a facsimile document over an IP network. We have developed and tested an intrusion mechanism, which is capable of intruding into the facsimile communication over the Public Switched Telephone Network (PSTN) section of the FOIP network without either communicating parties having any knowledge of intrusion taken place. Additionally, we describe the various techniques by which intrusion can take place over an IP network. Finally, we conclude by suggesting countermeasure to prevent the occurrence of such attacks on the FOIP network in the future.M.S., Electrical Engineering -- Drexel University, 200

Voice over IP

The area that this thesis covers is Voice over IP (or IP Telephony as it is sometimes called) over Private networks and not over the Internet. There is a distinction to be made between the two even though the term is loosely applied to both. IP Telephony over Private Networks involve calls made over private WANs using IP telephony protocols while IP Telephony over the Internet involve calls made over the public Internet using IP telephony protocols. Since the network is private, service is reliable because the network owner can control how resources are allocated to various applications, such as telephony services. The public Internet on the other hand is a public, largely unmanaged network that offers no reliable service guarantee. Calls placed over the Internet can be low in quality, but given the low price, some find this solution attractive. What started off as an Internet Revolution with free phone calls being offered to the general public using their multimedia computers has turned into a telecommunication revolution where enterprises are beginning to converge their data and voice networks into one network. In retrospect, an enterprise\u27s data networks are being leveraged for telephony. The communication industry has come full circle. Earlier in the decade data was being transmitted over the public voice networks and now voice is just another application which is/will be run over the enterprises existing data networks. We shall see in this thesis the problems that are encountered while sending Voice over Data networks using the underlying IP Protocol and the corrective steps taken by the Industry to resolve these multitudes of issues. Paul M. Zam who is collaborating in this Joint Thesis/project on VoIP will substantiate this theoretical research with his practical findings. On reading this paper the reader will gain an insight in the issues revolving the implementation of VoIP in an enterprises private network as well the technical data, which sheds more light on the same. Thus the premise of this joint thesis/project is to analyze the current status of the technology and present a business case scenario where an organization will be able to use this information

An empirical, in-depth investigation into service creation in H.323 Version 4 Networks

Over the past few years there has been an increasing tendency to carry voice on IP networks as opposed to the PSTN and other switched circuit networks. Initially this trend was favoured due to reduced costs but occurred at the expense of sacrificing the quality of the voice communications. Switched circuit networks have therefore remained the preferred carrier-grade voice communication network, but this is again changing. The advancement in improved quality of service (QoS) of real-time traffic on the IP network is a contributing factor to the anticipated future of the IP network supplying carrier-grade voice communications. Another contributing factor is the possibility of creating a new range of innovative, state-of-the-art telephony and communications services that acquire leverage through the intelligence and flexibility of the IP network. The latter has yet to be fully explored. Various protocols exist that facilitate the transport of voice and other media on IP networks. The most well known and widely supported of these is H.323. This work presents and discusses H.323 version 4 service creation. The work also categorises the various H.323 services and presents the mechanisms provided by H.323 version 4 that have facilitated the development of the three services I have developed, EmailReader, Telgo323 and CANS

ISPCell: an interactive image-based streaming protocol for wireless cellular networks

Remote interaction with immersive 3D environments with acceptable level of quality of experience has become a challenging and interesting research topic. Due to the high data volume required to provide a rich experience to the user, robust and effcient wireless transport protocols have yet to be developed. On the other hand, cellular network technology has been widely deployed and is growing fast. The provision of remote interactive 3D environments over wireless cellular networks has several interesting applications, and it imposes some unsolved issues. Node mobility creates unstable bandwidth, which is a problem when providing smooth interaction to users. Although PDAs and cell phones are low resource devices, which makes it prohibitive to load and render entire virtual environments, they can still render images with relative ease. Based on this idea, this paper proposes a streaming system which relies on an image-based rendering approach, and is composed of several modules: a packetization scheme for images, an image-based rendering approach based on view morphing and its corresponding RTP payload format, and finally a bandwidth feedback mechanism and rate control. This paper illustrates some of the problems faced in this area, and provides a first step towards their solutions. We discuss our algorithms and present a set of simulation experiments to evaluate the performance of the proposed schemes.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

ISPCell: an interactive image-based streaming protocol for wireless cellular networks

Remote interaction with immersive 3D environments with acceptable level of quality of experience has become a challenging and interesting research topic. Due to the high data volume required to provide a rich experience to the user, robust and effcient wireless transport protocols have yet to be developed. On the other hand, cellular network technology has been widely deployed and is growing fast. The provision of remote interactive 3D environments over wireless cellular networks has several interesting applications, and it imposes some unsolved issues. Node mobility creates unstable bandwidth, which is a problem when providing smooth interaction to users. Although PDAs and cell phones are low resource devices, which makes it prohibitive to load and render entire virtual environments, they can still render images with relative ease. Based on this idea, this paper proposes a streaming system which relies on an image-based rendering approach, and is composed of several modules: a packetization scheme for images, an image-based rendering approach based on view morphing and its corresponding RTP payload format, and finally a bandwidth feedback mechanism and rate control. This paper illustrates some of the problems faced in this area, and provides a first step towards their solutions. We discuss our algorithms and present a set of simulation experiments to evaluate the performance of the proposed schemes.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI