DDB Recommended by Clearwire

Dear Mr. Esteves:

    This letter is to report the satisfactory performance and reliability of DDB Unlimited’s R7 Series cabinets since its initial installation in Clearwire’s nationwide 4G Network.

    Clearwire is the pioneer in 4G and builder of the first 4G Network in the country. The Clearwire 4G mobile broadband network now reaches 130 million people in the U.S. and covers over 70 of the top U.S. markets. Our network expansion represents one of the fastest in history, and our 4G network is highly scalable and backed by a wealth of spectrum.

    DDB Unlimited’s R7 Series cabinet was first installed in our network in 2004 and has been in continuous service since then.

    Clearwire is using the R7 Series cabinet to house 4G network equipment at over 14,000 telecom sites nationwide.

    With over 14,000 cabinets deployed over the same number of telecom sites Clearwire has been successful in launching a nationwide network supporting 130 million customers. The cabinet has evolved since its conception to better suit our equipment needs with HVAC cooling so know DDB offers in-house engineering support to custom make a cabinet configuration for any application.

    DDB Unlimited’s product has performed reliably in these challenging applications since the initial installation. DDB Unlimited’s support of its products has been completely satisfactory, as well.

    I have no hesitation in recommending the R7 Series cabinet for acceptance by the RUS and addition to the “List of Materials”. The RUS may feel free to contact me if there are any questions about this letter or about our experience with DDB Unlimited and its products.

    Yours very truly,

Mark Heise
Systems Engineer