The OS904-MBH is a compact Carrier Ethernet purpose-built cell-site Demarcation device that enables high-quality timing synchronization over packet switched networks. High-quality timing synchronization is extremely important in 2G GSM, 2.5G GPRS, 3G UMTS and 4G LTE/WiMAX mobile networks for a successful call signal hand-off between cellular base stations. The OS904-MBH allows operators a migration to packet-switched networks without the loss of traditional TDM-quality synchronization to cellular base stations. The solution functions as an Ethernet Equipment Clock (EEC) and combines the two leading technologies existing for packet-switched networks synchronization: Physical layer Synchronization over Ethernet (SyncE) and Precision time Protocol (PTP -1588v2). By integrating both timing technologies, the OS904-MBH enables timing-gateway functionality between Synchronous and Asynchronous physical layer networks. Such flexibility enables end-to-end synchronization with maximum investment protection of the existing network infrastructure.