FIRST NODE AND METHODS PERFORMED THEREBY FOR HANDLING AGGREGATION OF MESSAGES

A method performed by a first node for handling aggregation of messages is disclosed. The first node determines out of a plurality of nodes, which nodes are to be paired as a pair of nodes. The pairing is to pass messages to another node for aggregation of information comprised in the messages. The information is to be masked by respective masks of opposite signs. The respective masks are to prevent the another node from accessing the information while enabling their aggregation. The determining is based on a respective measure of reliability of communications of a second node and a third node in the pair of nodes being similar, according to a criterion. The first node initiates an aggregation of the messages passed from the determined pair of nodes to the another node.