A novel distributed test architecture of transmitting IEEE 1149.1 Boundary Scan (a.k.a JTAG) Test Access Port (TAP) signals over a serial channel is presented in this paper. It is developed to facilitate the system testing and remote field update of distributed base stations (DBS) in a wireless network. The state-of-the-art DBS does not only improve the overall quality of wireless network services via its ability and ease to provide wider coverage in various environments, but also lowers the installation and operation costs as well as reduces the space requirements. However, the DBS poses great challenges for system testing and field update operation due to its distributed architecture. The proposed distributed test architecture enables the system testing as if the distributed units are on a backplane within the same chassis. In addition, the embedded boundary scan test software, that is running on the microprocessor of the controller board, takes advantage of the proposed distributed test architecture to update the configuration Programmable ROMs (PROMs) of the distributed units remotely without on-site visits. A novel slow-fast programming algorithm is also proposed for efficient remote field update in DBS to overcome significant fiber propagation delay. It reduces the time for PROM update from over an hour to less than 19 minutes over a 12km fiber.