Despite the pressures mounting on the Chinese vendors, Huawei continues to trumpet its leadership in 5G RAN, while ZTE is targeting pole position in the transport network. It has published a white paper to promote its solutions in this area, called ‘Meeting 5G Transport Requirements With FlexE’.
The white paper sets out the goals and key technologies of the 5G transport network and provides a technical blueprint. It identifies four main technology aspects, all (of course) supported by FlexE. These are on-demand bandwidth provision; ultra-low latency with ultra-stable jitter forwarding; ultra-high reliability; and flexible end-to-end network slicing.
For the first of these, the solution proposes large-port bonding to cope with the bandwidth upgrade needed for 5G, so that operators can move to 100GE bandwidth and beyond without sacrificing early investments.
The platform uses time slot cross-connection technology to support user service traffic forwarding, based on the physical layer, so that the user packet is not required to be parsed in the network intermediate node, and the service traffic forwarding can be completed in real time. This achieves single-hop device forwarding latency of less than 0.5 microseconds and jitter of less than 30 nanoseconds, laying a foundation for ultra-low-latency service transport, says ZTE.
For reliability, it extends OAM with channel-layer protection, aiming to improve the reliability of customer service transport. In case of a fault, the protection switching can be completed within 1ms, enabling the entire network to reach 99.9999% reliability.
Finally, operators can implement end-to-end slicing based on FlexE and FlexE Channel, as the network features TDM-like exclusive bandwidth and physical isolation, while supporting Ethernet statistical multiplexing. This enables slice forwarding separation, management separation, fault separation and protocol separation.
“Operators must address many challenges to meet the unique demands of coming 5G application scenarios, and the transport network will be essential to the large-scale 5G deployments. As a viable 5G transport solution, FlexE is gaining interest and attention of operators, and the new FlexE time-slot cross-connection technology is likely to be an efficient solution for hard network slicing,” said Sterling Perrin, principal analyst of Heavy Reading and author of the ZTE white paper.
Aspects of ZTE’s layered network architecture based on FlexE have been contributed to the standards process via the ITU-T G.mtn process.