Implementasi Trunk Interkoneksi Multi Server menggunakan Singleboard Komputer

Voice over Internet Protocol (juga disebut VoIP, IP Telephony, Internet telephony atau Digital Phone) adalah teknologi yang memungkinkan percakapan suara jarak jauh melalui media internet. Data suara diubah menjadi kode digital dan dialirkan melalui jaringan yang mengirimkan paket-paket data, dan bukan lewat sirkuit analog telepon biasa. Dalam komunikasi VoIP, pemakai melakukan hubungan telepon melalui terminal yang berupa PC atau telepon biasa. Dengan bertelepon menggunakan VoIP, banyak keuntungan yang dapat diambil diantaranya adalah dari segi biaya jelas lebih murah dari tarif telepon tradisional, karena jaringan IP bersifat global. IP Phone dapat di tambah, dipindah dan di ubah. Hal ini karena VoIP dapat dipasang di sembarang ethernet dan IP address, tidak seperti telepon konvensional yang harus mempunyai port tersendiri di Sentral atau PBX (Private branch exchange). Dalam penelitian ini mengimplementasikan keterhubungan antar server menggunakan single board computer yang di install sistem operasi Elastix yang bertujuan untuk mengimplementasikan prefix untuk antar server dan menggunakan beberapa codec audio. Hasil penelitian telepon menggunakan prefix dan tanpa prefix sebanyak 6 client atau 3 pasng panggilan secara bersamaan nilai packet loss tertinggi pada codec speex dengan prefix sebesar 2,34%. Nilai bandwidth tertinggi yang digunakan adalah dengan prefix codec PCMU dengan rata-rata 82,3 Kbps dan tanpa prefix 79,3 Kbps. Kata kunci : Server, VoIP, IP Telphony, Internet telephony, Digital Phone, IP Address, PBX, Codec, Prefix.

PENGARUH PENGGUNAAN CODEC STANDART ITU G.729 TERHADAP SISTEM KOMUNIKASI VOIP

Voice over Internet Protocol (VoIP) is a technology that is capable of passing voice traffic, in the form of packets through the network Internet Protocol (IP). IP network itself is a data communications network based packet-switch. The voice signal before experiencing bundled voice coding or format conversion of sound into digital form that can be passed over an IP network. Telephony, Internet telephony, or termed VoIP (Voice Over Internet Protocol.This communication system use VoIP (Voice over Internet Protocol), ie voice calls over data services (internet). This communication was developed using Android-based devices. Based on characteristics, android devices are open source, so users do not need to have a license to be able to have android-based devices. In addition, the android device that must be connected to a SIP (Session Iniation Protocol) is a data service that can be done with a paid subscription of the user of the operator using a conventional pulse. Telecommunications designed will use a hybrid system, the merger between VoIP communications with data communications GSM network. With basic calculations where Coding standards G 729, is a standard that can be used for voice communication system through data networks with rate of 8 Kbps. The implementation of the G729 codec is effect on communication systems VOIP.

Detecting Nuisance Calls over Internet Telephony Using Caller Reputation

Internet telephony permit callers to manage self-asserted profiles without any subscription contract nor identification proof. These cost-free services have attracted many telemarketers and spammers who generate unsolicited nuisance calls. Upon detection, they simply rejoin the network with a new identity to continue their malicious activities. Nuisance calls are highly disruptive when compared to email and social spam. They not only include annoying telemarketing calls but also contain scam and voice phishing which involves security risk for subscribers. Therefore, it remains a major challenge for Internet telephony providers to detect and avoid nuisance calls efficiently. In this paper, we present a new approach that uses caller reputation to detect different kinds of nuisance calls generated in the network. The reputation is computed in a hybrid manner by extracting information from call data records and using recommendations from reliable communicating participants. The behavior of the caller is assessed by extracting call features such as call-rate, call duration, and call density. Long term and short term reputations are computed to quickly detect the changing behavior of callers. Furthermore, our approach involves an efficient mechanism to combat whitewashing attacks performed by malicious callers to continue generating nuisance calls in the network. We conduct simulations to compute the performance of our proposed model. The experiments conclude that the proposed reputation model is an effective method to detect different types of nuisance calls while avoiding false detection of legitimate calls.

A Security Analysis on OpenSIPS

IP Telephony, Internet Telephony, Digital Phone or often also called VoIP (Voice Over Internet Protocol) is a technology that allows long-distance voice conversations with the Internet. The increasing number of VoIP users and other IP-based multimedia streaming services naturally raises security issues. Many users are likely to lose their privacy in communication. To overcome this security problem a security system must be implemented. Implementing a security system will use VPN Gateway using SSL and TLS encryption on the VoIP server. The VPN Gateway method is used to build a private network so that only certain users can use the private network. The TLS method is used to secure a user signaling session to the server. From the test results obtained that the VoIP server that uses VPN Gateway and TLS on the server can overcome the attacks e.g., eavesdropping, attacking authentication, teardown session, and denial of service.

An Instance of Internet Telephony over the Himalayas

This chapter assesses Alexander Kluge's Skype conversation with renowned Chinese literary scholar Wang Hui, recorded in the spring of 2012. The interview was held following a public screening of Kluge's documentary News from Ideological Antiquity (2008) subtitled in Chinese. A testimony to Kluge's desire to think beyond Europe's geographic and intellectual boundaries, the interview engages the viability of Marxist thinking in the age of globalization and testifies to the centrality of cooperation and collaboration in the form of dialogue for Kluge's essayism. Kluge also discusses fragmentary storytelling, which is already present in Tacitus, in his Roman historical writing. The fragmentary, he says, is what Walter Benjamin and Theodor W. Adorno teach people: people should use it. Kluge and Hui then further explores film. Kluge claims that the reality of film is not sealed off. This means that new possibilities remain open for film.

Efficient Detection of Attacks in SIP Based VoIP Networks Using Linear l1-SVM Classifier

The Session Initiation Protocol (SIP) is one of the most common protocols that are used for signaling function in Voice over IP (VoIP) networks. The SIP protocol is very popular because of its flexibility, simplicity, and easy implementation, so it is a target of many attacks. In this paper, we propose a new system to detect the Denial of Service (DoS) attacks (i.e. malformed message and invite flooding) and Spam over Internet Telephony (SPIT) attack in the SIP based VoIP networks using a linear Support Vector Machine with l1 regularization (i.e. l1-SVM) classifier. In our approach, we project the SIP messages into a very high dimensional space using string based n-gram features. Hence, a linear classifier is trained on the top of these features. Our experimental results show that the proposed system detects malformed message, invite flooding, and SPIT attacks with a high accuracy. In addition, the proposed system outperformed other systems significantly in the detection speed.