Texas Lone Star Network Selects Ribbon's IP Wave Solutions to Augment Network Capacity

Alien wavelengths support increased scale and service offerings

PLANO,Texas,May 17,2023 --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 TLSN,a consortium of 41 rural broadband service providers in Texas,has selected Ribbon to expand capacity in its statewide transport network.

"Ribbon is already proving itself to be a very flexible and dependable partner and offers us the services,expertise and flexibility we require," said Mike Miller,General Manager,TLSN. "Their solutions,pricing and support model enable us to support our members with a robust,high capacity network."

TLSN is leveraging Ribbon's compact Apollo 9603 platform with the TM400_2 (dual 400G transponder) to providealien wavelengths overlay on the existing ROADM transport network and connect rural and other underserved communities throughout Texas. The TM400_2 will initially be deployed in 200G coherent mode with 100GbE clients. As service requirements increase over time,the TM400_2 can be repurposed to support 400G links with 400GbE clients. TLSN and its members further benefit from 24*7 US-based support while gaining the ability to deploy the services their customers demand in today's always-on environment.

"TLSN is a key player in the Texas rural market and we're proud to be supporting them with our optimized,automated and open IP optical solutions. We look forward to further growing the relationship." said Elizabeth Page,Ribbon's Senior Sales Director,Rural Markets.

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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Media Contact

Catherine Berthier

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