MCI Sets Benchmark And Achieves Milestone For Managed LAN Services

Introduces Industry's First Actual "Time-to-Repair" Guarantee

Surpasses Milestone of 15,000 Managed LAN Devices

ASHBURN, Va., JULY 26, 2005-MCI, Inc. (NASDAQ: MCIP) today announced it is setting new performance thresholds for its Managed LAN Service with the industry's first actual "Time to Repair guarantee from Managed LAN to WAN. Since launching the service in December of 2004, MCI has already surpassed the 15,000 Managed LAN milestone, administering LAN devices around the world for enterprise customers such as NASDAQ.

"MCI's growth of its managed LAN business illustrates how we are delivering next-generation services that fit the evolving requirements of our business and government customers," said Nancy Gofus, senior vice president of MCI Product Management. "By stepping up our performance metrics from LAN to WAN, we are in stride with the rapid pace in which companies are making the move to Voice over IP."

MCI is extending its network restoration guarantee for Managed WAN Services to its Managed LAN customers, delivering high performance, reliability and restoration service guarantees throughout a customer's networking environment. The Company has improved its restoration service level agreement (SLA) to guarantee a 3.5 hour time to repair in the U.S., four hours in key global business centers, and six hours in remote regions of the world. Global business centers covered by the four-hour guarantee are located in Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Hong Kong, Ireland, Italy, Japan, Luxembourg, Netherlands, Norway, Singapore, South Korea, Spain, Sweden, Switzerland and the United Kingdom.

MCI also unveiled new performance guarantees for LAN device availability for workgroup and core LAN devices and for the first time a standard set of SLAs covering third-party networks. MCI is offering 99.5 percent availability for workgroup LAN devices and 99.95 percent availability commitments for core LAN devices. Following suit with its Managed Network Services third-party SLAs, MCI is extending its LAN service commitments to cover third-party networks, including monitoring, management, and ongoing maintenance. As a result, customers can take advantage of network diversity, while maintaining a single network management point-of-contact.

Other enhancements to MCI's comprehensive LAN service level agreements include:

• Up to 100 percent credit of the monthly management fee per device for missed performance metrics
• Guarantees based on actual time to repair versus mean time to repair
• Third party SLAs that match, or even beat, the provider of origin.

According to Yankee Group Vice President of Enterprise Infrastructure Research, Zeus Kerravala, one hour of network downtime can cost up to $4.5 million for a large enterprise. On average, enterprises estimate the cost of downtime of mission critical IT systems at roughly $40 per hour, per employee.

MCI's newly-enhanced SLAs are immediately available for all new Managed LAN Services. MCI's six-point guarantee includes service commitments for device availability, restoration, service installation, proactive outage notification, change management and configuration back-up. MCI supports all performance guarantees with financial credits.

MCI's Managed Network Services are available with the company's Managed Security, Hosting and Contact Center Services, as well as MCI Advantage, delivering a completely integrated voice and data solution. By utilizing one provider to build and maintain their networks, companies can better focus on their core business operations. MCI has been a Managed Network Services provider since 1989.

Today, MCI manages more than 3,100 customer networks in 149 countries, including overseeing more than 22,000 non-MCI connections from more than 60 network service providers globally.

About MCI, Inc.

MCI, Inc. (NASDAQ: MCIP) is a leading global communications provider, delivering innovative, cost-effective, advanced communications connectivity to businesses, governments and consumers. With one of the most expansive global IP backbones and wholly-owned data networks, MCI develops the converged communications products and services that are the foundation for commerce and communications in today's market. For more information, go to www.mci.com.