Cisco ASR1002-5G-SHA/K9 Software Guide - Page 297

10 C H A P T E R Synchronous Ethernet Support Synchronous Ethernet (SyncE) defined by the Telecommunication Standardization Sector (ITU-T) standards, such as G.8261 and G.8262, leverages the PHY layer of the Ethernet to transmit clock information to the remote sites. This chapter covers the following topics: • Synchronous Ethernet Overview • Synchronization Status Message and Ethernet Synchronization Messaging Channel • Restrictions and Usage Guidelines • Configuring Synchronous Ethernet Synchronous Ethernet Overview SyncE over Ethernet provides a cost-effective alternative to the Synchronous Optical Networking (SONET) networks. For SyncE to work, each network element along the synchronization path must support SyncE. To implement SyncE, the bit clock of the Ethernet is aligned to a reliable clock that is traceable to the Primary Reference Clock (PRC). Cisco ASR 1000 Series Routers have a dedicated external interface known as BITs interface to recover clock from a Synchronization Supply Unit (SSU). ASR 1000 router uses this clock for SyncE. The BITS interface supports E1(European SSUs) and T1 (American BITS) framing. Table 10-1 lists the framing modes for a BITS port on a Cisco ASR 1000 Series Router: Table 10-1 Framing Modes for a BITS Port on a Cisco ASR 1000 Series Router BITS or SSU Port Support Matrix T1 T1 E1 E1 E1 E1 2048 kHz Framing Modes Supported T1 ESF T1 SF E1 CRC4 E1 FAS E1 CAS E1 CAS CRC4 2048 kHz SSM or QL Support No No No No No No No Tx Port No No No No No No No Rx Port Yes Yes Yes Yes Yes Yes Yes OL-16506-10 Cisco ASR 1000 Series Aggregation Services Routers Software Configuration Guide 10-1