Resumen
In recent years, the proliferation of the Internet of Things (IoT) has kick started the home and office automation in a very rapid manner. The paper demonstrates a cost effective implementation of an IoT system for managing the visitors in an office environment. The automation system comprises low cost NodeMCU based Wireless Transmitter, NodeMCU based Wireless Display Unit and an android mobile phone. The mobile phone also serves as wireless Access Point to which the Wireless Transmitter and the Wireless Display Units are wirelessly connected for exchanging the messages using UDP protocol. The Wireless Transmitter and the Wireless Display Units are kept in the visitor?s waiting area. The consulting person possesses an android mobile phone in which the automation software is installed. The visitor enters a message using the Wireless Transmitter and notes down the acknowledgement token number sent by the automation software. When the consulting person checks this message, the same token number is sent to the Wireless Display Unit signaling the visitor to consult the person.