LOS ANGELES & SAN DIEGO, CA —AUGUST 17, 2004 -- Mpower Communications Corp. (AMEX:MPE), a leading provider of broadband Internet access and telephone services to business customers, and CSCI Inc., a leading provider of managed security services, today announced an agreement in which Mpower will offer CSCI’s OfficeScreen managed firewall and VPN services to its business customers.

Mpower’s suite of dedicated and integrated T1 products operate over a leading-edge facilities-based IP network that supports both voice and data. VPN and managed firewall services are natural extensions of this network and will provide a cost-effective alternative for customers with multiple and/or virtual locations.

“Internet and systems security are increasingly important in today’s business marketplace. By bundling Managed Security and VPN services with our integrated voice and data products, we will now be able to offer an end-to-end solution for companies that need secure broadband connectivity for remote offices and mobile users,” noted Mpower Communications New Technology Officer Russ Shipley. “We are pleased to partner with CSCI, an experienced provider with an outstanding reputation in the security and wide area network arena, and offer its world-class OfficeScreen product to our customers.”

To provide its services, OfficeScreen leverages Juniper Networks NetScreen security products, best-in-class network firewall and IPSec virtual private network (VPN) appliances. These powerful units are installed, configured, updated and monitored 7x24 by CSCI’s Security Operation Center and the Pro-Assist engineering services group. This allows small businesses and distributed enterprises to protect their networks from Internet threats and viruses without the overhead of dedicated IT staff or the major capital outlay traditionally required for VPN implementation.

“Small to medium-sized companies are rapidly adopting Internet VPN technology as their choice of wide area network connectivity, increasingly using VPN to reduce costs associated with older WAN technologies like Frame Relay and Point-to-Point networks. They are realizing that a VPN can be a powerful tool that is affordable and scalable,” said Rich Tear, CSCI’s CEO. “Mpower is already addressing the telecommunications needs of small- to medium-sized businesses and their understanding of that market makes us especially enthusiastic about partnering with Mpower as they add managed security to their portfolio of services.

”Mark Smith, vice president of Worldwide Sales at Juniper Networks , added, “Juniper Networks is pleased that Mpower has selected the OfficeScreen line of managed security services on the NetScreen security product line. CSCI's expertise and specialization on our appliances and systems will allow Mpower customers to enjoy the full extent of Juniper Networks product capabilities without the cost of well trained salary or hourly IT personnel. This can help Mpower become a one-stop-shop for SME businesses looking to reduce their wide area network costs using best-in-class technology.”

About Mpower Communications

Mpower Communications (AMEX:MPE) is a facilities-based broadband communications provider established in 1996. Mpower offers a full range of data, telephony, Internet access and Web hosting services for small and medium-size business customers. Further information about the company can be found at www.mpowercom.com.

About CSCI

Founded in 1985, CSCI, Incorporated is a privately held systems integration company, specializing in security, LAN/WAN connectivity, network and consulting services. The company staffs itself with the industries best trained consultants and engineers, training continually on the most current hardware and software solution, diverse platform and certifications. www.csci.com .
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