SUNAB, Svenska UMTS-nät AB, is a company jointly owned by Tele2 Sverige AB and TeliaSonera AB for the purpose of building, owning and operating a 3G network for the parent companies. SUNAB was formed in 2002.The joint network operated by SUNAB is the largest 3G network in Sweden, both by coverage and customer base.SUNAB is operated as a multi-operator core network (MOCN) and was one of the very first in the world.