Ribbon's Comprehensive STIR/SHAKEN Solution Enables Colt to Meet French Market Regulatory Mandates

Cloud-based service enables quick deployment of a complete solution for compliance

PLANO,Texas,Feb. 9,2023 --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 global digital infrastructure company Colt Technology Services (Colt) has selected Ribbon's STIR/SHAKEN as a Service. STIR/SHAKEN complements Ribbon's services Session Border Controller and Policy & Routing Serverwhich are already in use by Colt to ensure caller identity in compliance with French government mandates.

"Working with Ribbon enables us to meet our regulatory obligations within the required timelines," said Robin Farnan,Executive Vice President – Operations and Engineering,Colt Technology Services. "By leveraging cloud technologies,we benefit from a fast and seamless deployment while protecting our customers from calls that range from simply annoying to malicious,delivering a more positive customer experience."

Already deployed within multiple carriers in France and the US,Ribbon's STIR/SHAKEN is a complete solution designed to meet regulatory compliance requirements for call authentication,signing,verification and certificate management,which can be easily and quickly deployed in service provider networks in order to help ensure caller identity and minimize fraudulent calls. Ribbon's STIR/SHAKEN as a Service solution leverages Ribbon's Identity Hub,an innovative,cloud-based platform that enables identity assurance services without the need to deploy on-premises equipment.

"Ribbon is taking a leading position in supporting carriers against the unwanted and even dangerous calls that come with alarming regularity," said Dan Redington,Ribbon's Executive Vice President,Global Sales. "We have a longstanding relationship with Colt and are pleased to help them protect their customers in France with our STIR/SHAKEN solution."

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.

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Catherine Berthier

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