IAB stands for the Internet Architecture Board. The IAB is a committee of the Internet Engineering Task Force (IETF). According to the IETF website at IAB the IETF "responsibilities include architectural oversight of IETF activities, Internet Standards Process oversight and appeal, and the appointment of the RFC Editor. The IAB is also responsible for the management of the IETF protocol parameter registries."
The IAB manages and publishes requests for comments (RFCs) and oversees the internet standards process. The IAB supervises architectural additions or proposed changes for internet network protocols.