The Internet of Things (IoT) connects billions of smart devices, sensors, and actuators that continuously exchange data over communication networks. Efficient communication protocols are essential to ensure reliable, secure, scalable, and low-power communication among these devices. Two of the most important protocols used in IoT environments are IPv6 and MQTT, each serving different purposes in the communication architecture. a) IPv6 Internet Protocol Version 6 (IPv6) is the latest version of the Internet Protocol developed to overcome the limitations of IPv4, particularly the shortage of IP addresses. IoT ecosystems require unique addresses for billions of connected devices, making IPv6 an ideal solution due to its 128-bit addressing scheme, which provides an enormous address space. IPv6 enables every IoT device to have a globally unique IP address, allowing direct communication across the Internet without requiring Network Address Translation (NAT). This feature simplifies device connectivity and improves network efficiency. The protocol also supports automatic address configuration through Stateless Address Autoconfiguration (SLAAC), enabling IoT devices to configure their own IP addresses without requiring manual intervention or dedicated servers. Another important feature of IPv6 is its improved routing efficiency. The simplified packet header reduces processing overhead and allows routers to forward packets more efficiently. This is particularly beneficial for IoT applications where low latency and quick communication are essential, such as industrial automation, healthcare monitoring, and smart transportation. IPv6 also incorporates enhanced security through mandatory support for Internet Protocol Security (IPsec). IPsec provides authentication, confidentiality, and data integrity, protecting IoT communications from unauthorized access and tampering. Although implementation depends on system requirements, IPv6 offers a stronger security foundation compared to