Low-cost wireless mesh communications based on openWRT and voice over internet protocol

Technology makes it easier for us to communicate over a distance. However, there are still many remote areas that find it difficult to communicate. This is due to the fact that communication infrastructure in some areas is expensive to build while the profit will be low. This paper proposes to combine voice over internet protocol (VoIP) over mesh network implemented on openWRT router. The routers are performing mesh functions. We set up a VoIP server on a router and enabled session initiation protocol (SIP) clients on other routers. Therefore, we only need routers as a means of communication. The experiment showed very good results, in the line-of-sight (LOS) condition, they are limited to reception distances up to 145 meters while in the non-line-of-sight (NLOS) condition, they are limited to reception distances up to 55 meters.

Analisis Implementasi Media Komunikasi Berbasis IP Menggunakan Arterisk Freepbx

Voice over Internet Protocol (VoIP) merupakan teknologi yang memanfaatkan Internet Protocol untuk menyediakan komunikasi voice secara elektronis dan real-time. Unsur pembentuk VoIP adalah User agent, Proxy, Protocol dan Coder-Decoder (CODEC). Asterisk merupakan softswicth untuk mengoperasikan proxy, yang berbasis session initiation protocol (SIP). Tujuan dari penelitian ini adalah membangun server VoIP berbasis Asterisk, agar dapat dikembangkan pada penelitian selanjutnya sesuai dengan kebutuhan. Penelitian ini dilakukan pada instalasi yang sudah dibangun jaringan internet sebelumnya. Sehingga VoIP disini difungsikan sebagai pemaksimalan jaringan internet yang sudah ada tersebut untuk menekan biaya pengeluaran kebutuhan komunikasi. Layanan yang disediakan pada penelitian ini berbentuk voice dan video dengan layanan call client to server, call client to client, video call conference, video conference.

Survey of Countering DoS/DDoS Attacks on SIP Based VoIP Networks

Voice over IP (VoIP) services hold promise because of their offered features and low cost. Most VoIP networks depend on the Session Initiation Protocol (SIP) to handle signaling functions. The SIP is a text-based protocol that is vulnerable to many attacks. Denial of Service (DoS) and distributed denial of service (DDoS) attacks are the most harmful types of attacks, because they drain VoIP resources and render SIP service unavailable to legitimate users. In this paper, we present recently introduced approaches to detect DoS and DDoS attacks, and classify them based on various factors. We then analyze these approaches according to various characteristics; furthermore, we investigate the main strengths and weaknesses of these approaches. Finally, we provide some remarks for enhancing the surveyed approaches and highlight directions for future research to build effective detection solutions.