VoIP applications become popular in recently years, and more and more network researchers are interested in VoIP issues. However, users are used to using the traditional telephony number to make calls. This is because the telephony number is more convenient than the meaningless IP address and the diffusive domain name in VoIP networks. They are really hard to remember. In this paper, we discuss the design and implementation of ENUM (tElephone NUmber Mapping) service over a SIP user agent. According to the technology of ENUM (RFC2916), the dialed numbers can be encoded into E.164 numbers. By querying the DNS, we can get the SIP URI (Universal Resource Identifier) which exists in the NAPTR (Naming Authority Pointer) resource records. The ENUM service plays an important role between the traditional telephony networks and the VoIP networks. The users can be unaware of the different operation style in VoIP.

With the rapid growth of communication, various communication equipments get rid of the stale and bring forth the fresh. The frequently used communication device is not limited to domestic telephone any longer. We can achieve the same functionality as traditional telephone by the use of VoIP¡]Voice over IP¡^over the Internet. The common fraction of these communication products is the user identity which may be achieved by either a telephone number or an URI (Universal Resource Identity). In this paper, we implement a distributed system with load balancing. This is achieved by utilization of ENUM. It can distribute the load of the traditional server to several servers to enhance the reliability of services. For the future combination of VoIP and the traditional PSTN, we expect to provide more consistent services while the number of user is increasing.

ENUM is the mapping of a telephone number from the PSTN to Internet services-telephone number in, URL out. It was developed as a solution to the question of how to find services on the Internet using only a telephone number. / Workshop "Netz- und Service-Infrastrukturen" ENUM = tElephone NUmber Mapping, definiert die Vorschrift, mit der eine klassische Telefonnummern auf eine Domain eindeutig abgebildet wird (dafür wird DNS genutzt). Das Ziel dabei ist, verschiedene Adressen, Nummern und URLs eines Benutzers unter einer einzigen Rufnummer verfügbar zu machen.

Zugl.: Mainz, Universiẗat, Diss., 2008.

Master's Thesis is engaged on possibilities connect SIP server to telephone network on FIT. The main reason is that employees can call to university, when they are out of faculty. For resolution we will use SIP server Asterisk, which will be serving as authorization server for users. Next Asterisk will ensure transmission numbers to SIP address with ENUM. In the practical part we will verify the functionality.

IP networks have become an increasingly protable option over traditional communication networks. Despite the advantages of VoIP compared to PSTN, it is not possible to replace one technology by the other instantly, due to the complexity involved. This implies a transition period in which the two technologies will coexist. In order to make this feasible, there must be a system for mapping E.164 numbers (used in the PSTN) to URIs (used in the IP network). In this context, the ENUM protocol is gaining prominence as the most promising solution. However, it is not very spread yet. In addition, there are technical issues and especially political and economic interests that need to be worked so that this protocol can be popularized. Regarding technical issues, there is a shortage of tools for the study of this protocol. Thus, this dissertation proposes a simulation platform that enables the study of the ENUM protocol. The project design of the simulator was based on experiments carried out in the laboratory, the proposition of mathematical models and, subsequently, implementation, integration and validation of the simulator. The results indicate that the simulation platform rightly describes the real system considered. The results also proved the success of the proposed modeling strategy. In addition, new modules were developed for the NS-3 simulation environment, oering new opportunities for researchers. / As redes IP têm se tornado uma opção cada vez mais vantajosa em relação às redes de comunicações tradicionais. Mesmo diante das vantagens oferecidas pela tecnologia VoIP em relação à PSTN, não é possível uma substituição instantânea de uma tecnologia pela outra devido à complexidade envolvida. Isto implica em um período de transição em que as duas tecnologias irão conviver. Para que isto seja realizável, é necessário que exista um sistema de mapeamento entre números E.164 (utilizados na PSTN) e URIs (utilizados na rede IP). É neste contexto que o protocolo ENUM vem ganhando destaque como a solução mais promissora. Entretanto, a sua disseminação ainda é baixa. Além disso, existem questões técnicas e, principalmente, interesses políticos e econômicos que precisam ser trabalhados para que este protocolo seja popularizado. Em relação às questões técnicas, existe uma escassez de ferramentas para o estudo deste protocolo. Neste sentido, esta dissertação apresenta uma proposta de plataforma de simulação que possibilite o estudo do protocolo ENUM. Dessa maneira, o projeto de concepção do simulador foi baseado na realização de testes em laboratório, na proposição de modelos matemáticos e, posteriormente, na implementação, integração e validação do simulador. Os resultados indicam que a plataforma de simulação descreve com delidade o sistema real considerado. Os resultados também comprovaram o sucesso da estratégia de modelagem proposta. Além disso, novos módulos foram desenvolvidos para o ambiente de simulação NS-3, oferecendo novas possibilidades para os pesquisadores da área. / Mestre em Ciências

ENUM is the mapping of a telephone number from the PSTN to Internet services-telephone number in, URL out. It was developed as a solution to the question of how to find services on the Internet using only a telephone number. / Workshop "Netz- und Service-Infrastrukturen" ENUM = tElephone NUmber Mapping, definiert die Vorschrift, mit der eine klassische Telefonnummern auf eine Domain eindeutig abgebildet wird (dafür wird DNS genutzt). Das Ziel dabei ist, verschiedene Adressen, Nummern und URLs eines Benutzers unter einer einzigen Rufnummer verfügbar zu machen.

This Master’s Thesis concerns the technical problems and solutions in the Telia Mobile’s Golden Gate Architecture. The Golden Gate project will bridge service control from the IPnetwork to the circuit switched network. Connecting the different users of PSTN, GSM, W-LAN, and GPRS networks together will require solutions to many problems. Most of the problems have already been defined by Telia. Our task is to evaluate two parts of the Golden Gate architecture, namely the Interconnect- and Service Provider roles. The Interconnector provider connects networks of different technical standards and enables other network operators to reach Service Providers on the Internet or other IP-based networks. The role concerns mainly mapping between SS7 signaling and the Session Initiation Protocol (SIP), charging and billing. Via the Interconnector the Service Provider can connect different services to any network. We will describe the SIP-protocol in detail and then we will look into the mapping between SS7 and SIP. We will also propose a charging model. It is important to have a solution that supports roaming between the different networks, we will evaluate such a solution. Most of the protocols (INAP, ENUM, MAP and ISUP) that are involved in the Golden Gate architecture are not completely defined. There are many Internet Drafts that discuss the possible functionality of the protocols and the interworking between them. Many different Internet-workgroups are working with these issues. No one seems to have the right answers for the interconnection between the protocols involved. Since the IP-telephony will probably replace today’s telephony systems, it is important to ensure a suitable Quality of Service (QoS), security that guarantees privacy, and a fair billing function. These are the three major problems in the IP-telephony world. IP-Telephony or Voice over IP (VoIP) has been on the market for a long time, there are many 'free IP-call sites' that use VoIP, but the quality of the calls are not yet good enough to replace traditional telephony. Our task here is to make sure that the necessary quality of service is provided, and a reliable charging model is used.