 PLANO, Texas, April 28, 2021 PRNewswire -- Ribbon Communications Inc. Nasdaq: RBBN, a global provider of real-time communications software and IP optical transport solutions to service providers, enterprises, and critical infrastructure sectors, today announced its financial results for the first quarter of 2021. Revenue for the first quarter of 2021 was 193 million, compared to 158 million for the first quarter of 2020, an increase of 22. 