O princípio da eficiência administrativa na regulação da prestação do serviço de voz sobre internet - VoIP

The present work aims to demonstrate the link of the principle of efficiency - as expressed in the Constitution of 1988, by Constitutional Amendment No. 19 - with regulatory agencies, more specifically the ANATEL (National Telecommunications Agency). It also includes this principle’s importance to regulation - to monitor and manage public services - as well as when an activity will be considered efficient, keeping in mind that agencies are subjected to other principles of public administration. The increasing use of telephony has enabled further development of technologies that provide improvements in the provision of this service. The VoIP (Voice over IP), is nothing more than a technological breakthrough that directly targets the providers of conventional telephone service, both by modifying the business working for a long time with the same technology as the amount of new competitors’ dispute on market share. It also analyses the difficulty of understanding and definition of what is VoIP telephony, its growth and the threats that the traditional and mostly which is ANATEL’s role concerning this telephony technology. As regulator of the telecommunications service, ANATEL not yet regulated the voice telephony service using the IP protocol. What looks over the years is that ANATEL exercise its regulatory function to provide better conditions for competition among providers of VoIP and traditional telephone companies, obviously some difficulties are expected, given that VoIP is a technology that provides two services, through conventional telephony and using the internet.

Uma arquitetura baseada em SCTP e SIP para suporte a aplicações VoIP móveis e a especificação formal do seu módulo de controle

New versions of SCTP protocol allow the implementation of handover procedures in the transport layer, as well as the supply of a partially reliable communication service. A communication architecture is proposed herein, integrating SCTP with the session initiation protocol, SIP, besides additional protocols. This architecture is intended to handle voice applications over IP networks with mobility requirements. User localization procedures are specified in the application layer as well, using SIP, as an alternative mean to the mechanisms used by traditional protocols, that support mobility in the network layer. The SDL formal specification language is used to specify the operation of a control module, which coordinates the operation of the system component protocols. This formal specification is intended to prevent ambiguities and inconsistencies in the definition of this module, assisting in the correct implementation of the elements of this architecture

Uma ferramenta de manipulação de pacotes para análise de protocolos de redes industriais baseados em TCP/IP

This work presents a packet manipulation tool developed to realize tests in industrial devices that implements TCP/IP-based communication protocols. The tool was developed in Python programming language, as a Scapy extension. This tool, named IndPM- Industrial Packet Manipulator, can realize vulnerability tests in devices of industrial networks, industrial protocol compliance tests, receive server replies and utilize the Python interpreter to build tests. The Modbus/TCP protocol was implemented as proof-of-concept. The DNP3 over TCP protocol was also implemented but tests could not be realized because of the lack of resources. The IndPM results with Modbus/TCP protocol show some implementation faults in a Programmable Logic Controller communication module frequently utilized in automation companies