In 1Q18, the market for IMS equipment (wireline + wireless/VoLTE) contracted 19% compared to 4Q17 and was down 11% compared to 1Q17. The sequential decrease was largely due to seasonal factors as well as a slower than expected migration to VoLTE services. In 2017, the total market was essentially flat as wireless/VoLTE investments grew by 6%, which offset a 20% decline in wireline spending. We expect that the migration away from legacy circuit- and NGN-based systems will continue in 2018 and that the market will grow by 5% as the wireline segment contracts by 8% and wireless/VoLTE market grows by 8%.
In 1Q18, based on revenues the market leaders were: Nokia, Ericsson, and Huawei.