Building on the success of the Cisco^® Network Convergence System 5501 (NCS-5501) the Cisco Network Convergence System 55A1-24Q6H-S (NCS-55A1-24Q6H-S) offers improvements designed to meet the challenges of the zettabyte era. The NCS-55A1-24Q6H-S provides dense 1GE/10GE/25GE/100GE functionality in a 1-rack-unit package with line-rate MACsec and Precision Time Protocol (PTP) Synchronous Ethernet (SyncE)/1588 Class B timing. With its ultra-low per-bit power consumption deep packet buffering and optimized forwarding architecture the NCS-55A1-24Q6H-S has the flexibility to be deployed across various network roles including 5G Mobile Backhaul Top of Rack (ToR) spine-and-leaf and Converged Interconnect Network (CIN). Built to take full advantage of the advanced capabilities you have come to expect from Cisco IOS^® XR the NCS-55A1 fixed chassis models boast advanced packet classification segment routing ultra-wide Equal-Cost Multipathing (ECMP) programmable network management and telemetry to make your network smarter faster and more agile.