Ribbon Partners with Kontron Transportation to Upgrade SNCF Voyageurs Optical Communications Network

New Optical Transport Network enables one of Europe's largest railway companies to quickly scale to meet growing bandwidth demands,improve operational efficiencies,and enhance network reliability

PLANO,Texas,May 9,2022 --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 its longtime partner Kontron Transportation has been awarded the Transilien SNCF VoyageursOptical Transport Network (OTN) project to upgrade SNCF's communications network. The project involves replacing obsolete WDM (Wavelength Division Multiplexing) equipment in the Paris region with Ribbon's next-generation WDM,including OTN switching technology,part of its IP Waveportfolio.

"We are delighted to extend our relationship with our longtime partner Kontron Transportation to help one of the largest and most important transportation companies in Europe upgrade their communications network to the latest in WDM including OTN switching technology," said Sam Bucci,Executive Vice President & General Manager of Ribbon's IP Optical Networks Business Unit. "As an integral part of our IP Wave portfolio,our Optical solutions support some of the world's most vital critical infrastructure sectors including large railway operators like SNCF Voyageurs,helping them dramatically improve their network performance,capacity and reliability."

Kontron Transportationwill develop convergent IP (IP/MPLS,MPLS/TP) and optical networking solutions (WDM/OTN) through its expanded partnership with Ribbon. The new network offers SNCF Voyageurs several benefits including increased scalability to handle growing network demands; flexibility in routing services across the network; and the ability to guarantee highly flexible,secure operations communications and services.

"This is a significant milestone on the way to switching from conventional transmission to optical technology on mission-critical networks," said Richard Bussienne VP Mission Critical Networks Kontron Transportation Western Europe. "We are proud,that SNCF Voyageurs selected Kontron Transportation and our partner Ribbon for this important project."

The extensive Kontron-Ribbon solution also delivers the following:

A Multi-Tier Core-Aggregation-Access OTN Switching Architecture,based on Ribbon's 9904X Metro OTN and 9901X Access OTN switches;

A high availability network management system (NMS) with disaster recovery protection;

World-class professional services support of Kontron deployments including training and skills transfer.

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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About Kontron Transportation

Kontron Transportation is a leading global supplier of end-to-end communications solutions for mission-critical and carrier networks. The portfolio includes GSM-Railways,FRMCS,TETRA,DMR,LTE solutions for mission critical networks as well as mobility solutions for the public transport sector and is enabled through a comprehensive service value chain. A further mission is to provide a critical E2E IIoT solution dedicated for railway operators. Kontron Transportation invests in research and development and is an associated member of the European research initiative Shift2Rail. Kontron Transportation is part of S&T group and headquartered in Vienna (Kontron Transportation Austria AG) with main subsidiaries in Belgium,France,Germany,Portugal,Spain,the Czech Republic and United Kingdom. For more info visit kontron.com/ktrdn.

Media Contact

Susanne Schalek

Kontron Transportation Austria AG

T:+43 50811 3600| M:+43 664601911880

susanne.schalek@kontron.com