By 2003, Sprint/Nextel had assembled and grown its network by acquiring frequencies in the 800 and 900 MHz bands side by side with other Commercial Mobile Radio Systems (CMRS), Business Radio and Industrial/Land Transportation Radio (B/ILT) systems and public safety entities. The result was a network based on fragmented spectrum that often created interference issues with Public Safety. To address these problems, Nextel submitted a proposal to the FCC to realign the 800 MHz band and provide each user segment with access to a contiguous block of spectrum. This proposal required that frequency owners swap spectrum space. In addition to coordination with the FCC, the affected parties needed to reengineer much of their deployed equipment to transmit on the new frequencies.