Ribbon Wins TIA QuEST Forum Sustainability Award for Excellence in Network Equipment Sustainability

Highlights continued sustainability engagement

PLANO,Texas,June 30,2022 --Ribbon Communications Inc. (Nasdaq: RBBN),a global provider of real time communications technology and IP optical networking solutions to many of the world's largest service providers,enterprises,and critical infrastructure operators to modernize and protect their networks,today announced that it has won the 2021 Award for Excellence in Network Equipment Sustainability in the TIA QuEST Forum Sustainability Awards.

"This award underscores our commitment to furthering our sustainability practices,including our pledge to reduce direct carbon emissions by 30% by 2030. We,and our industry as a whole,can make a real difference in the battle against climate change. Our customers expect it,and we demand it from ourselves," said Patrick Macken,Ribbon's Executive Vice President and Chief Legal Officer. "I want to thank the internal teams who have been relentless in driving these improvements forward – their efforts are being justly recognized."

The annual awards leverage the TIA's Sustainability Assessor Tool and recognize companies for their outstanding performance and innovation in sustainability practices.

Ribbon received 100% or "Best in Class" scores in the areas of Corporate Social Responsibility (CSR),Supply Chain Management,Stakeholder Engagement and Organizational Engagement and Capabilities,in addition to high ratings in the six other categories scored by the TIA Assessment tool. This is the third time that Ribbon or its component companies have been honored by the TIA QuEST Forum awards,showcasing the company's ongoing focus and dedication.

"We approach sustainability from multiple angles,including industry certifications,environmental and HR KPIs,and ongoing assessments that examine and validate our efforts. We are honored to have received this recognition," Mr. Macken added.

About Ribbon

Ribbon Communications (Nasdaq: RBBN) delivers communications software,IP and optical networking solutions to service providers,enterprises and critical infrastructure sectors globally. We engage deeply with our customers,helping them modernize their networks for improved competitive positioning and business outcomes in today's smart,always-on and data-hungry world. Our innovative,end-to-end solutions portfolio delivers unparalleled scale,performance,and agility,including core to edge software-centric solutions,cloud-native offers,leading-edge security and analytics tools,along with IP and optical networking solutions for 5G. We maintain a keen focus on our commitments to Environmental,Social and Governance (ESG) matters,offering an annual Sustainability Report to our stakeholders. To learn more about Ribbon,please visit rbbn.com.

Important Information Regarding Forward-Looking Statements

The information in this release contains forward-looking statements regarding future events that involve risks and uncertainties. All statements other than statements of historical facts contained in this release,including those regarding the expected benefits from use of Ribbon Communication's products,are forward-looking statements. The actual results of Ribbon Communications may differ materially from those contemplated by the forward-looking statements. For further information regarding risks and uncertainties associated with Ribbon Communications' business,please refer to the "Risk Factors" section of Ribbon Communications' most recent annual or quarterly report filed with the SEC. Any forward-looking statements represent Ribbon Communications' views only as of the date on which such statement is made and should not be relied upon as representing Ribbon Communications' views as of any subsequent date. While Ribbon Communications may elect to update forward-looking statements at some point,Ribbon Communications specifically disclaims any obligation to do so.

Investor Contact

+1 (978) 614-8050

ir@rbbn.com

Media Contact

Catherine Berthier

+1 (646) 741-1974

cberthier@rbbn.com