Articles by Fábio Cosme

SIP TRUNK - The telephone channel over IP

Written by Fábio Cosme - 31 October 2023

In the RCTS VoIP network, the term SIP Trunk is often used to refer to the interconnection of our VoIP equipment with operators. read more

High-speed Internet to accelerate knowledge

Connectivity Knowledge

Written by João Nuno Ferreira - 24 November 2023

Networks play a fundamental role in science and academia. They connect teaching and research institutions and provide digital services that help researchers and students. read more

Malware attack by e-mail. What it is and how to protect yourself.


Written by João Machado - 19 October 2023

It is crucial to know the threats that can attack your organization and how to mitigate them. One such threat is malware, which often infiltrates organizations through seemingly harmless emails. read more

eSIM: The New "Card

Connectivity Knowledge

Written by Fábio Cosme - 28 June 2023

We are all familiar with the famous little removable card used in mobile devices to identify the user of a telephone operator's network, the... read more

ENUM: The famous unknown


Written by Fábio Cosme - 31 May 2023

ENUM is perhaps the most talked about protocol of the RCTS VoIP network and the pillar on which the network exists. But after all, what is ENUM? read more

SDP: Session Description Protocol - Are we in business?


Written by Fábio Cosme - 28 April 2023

Hand in hand with SIP, the Session Description Protocol (SDP), is a key protocol for VoIP and the RCTS VoIP network. This article explores the importance of SDP and how it is used to negotiate voice session characteristics. read more

RTP: The protocol that guarantees your voice in VoIP calls


Written by Fábio Cosme - 31 March 2023

Responsible for transmitting audio and video data in real time, RTP, or Real-time Transport Protocol, is a protocol used in voice over IP (VoIP) communications. read more

The Session Initiation Protocol (SIP): How digital communication became easier


Written by Fábio Cosme - 28 February 2023

Because of its wide compatibility between devices and because it is an open and flexible protocol, SIP, considered the standard protocol, is the main star... read more

What is VoIP?


Written by Fábio Cosme - 01 June 2022

The invention of the telephone revolutionized the world in the late 19th century and provided communication between two people over long distances, modernizing the way... read more