Stefano Ruffini

Synchronous ethernet: a method to transport synchronization

This article discusses the evolving transport architecture, covering some of the synchronization distribution problems to many endpoints where mobile backhaul and TDM emulation occur. It shows how synchronous Ethernet fits into both the Ethernet and synchronization architectures, and discusses how this helped development in standardization bodies. Standardization allows the key building blocks of Ethernet silicon and specific timing devices to be developed, which allows a robust system implementation to be constructed while allowing interworking with and migration from existing SONET/SDH-based transport infrastructure. Finally, results are shown that indicate a very high level of performance is achievable with Synchronous Ethernet not subject to the normal packet delay variation and traffic load conditions that can occur in packet based networks.

Synchronization aspects in LTE small cells

This article addresses the synchronization needs for mobile backhaul networks when deploying LTE small cells. Existing synchronization solutions for both FDD and TDD macro networks are discussed as well as the applicability of those solutions to small cells deployed in LTE TDD and LTE FDD networks. The benefits of using radio coordination features in a small cell environment and the corresponding demands placed on synchronization solutions are highlighted. Potential issues relating to synchronization of small cells are also discussed, and some additional synchronization solutions are proposed to address those issues.

Development of the first IEEE 1588 telecom profile to address mobile backhaul needs

This article describes the work performed by ITU-T SG15Q13 for defining the first telecom profile based on the use of IEEE Std 1588-2008. The first profile is specifically developed for the distribution of frequency using unicast IPv4 transmission, and required adaptation of the IEEE1588 protocol to make it suitable for the telecom environment. The objectives, reasons, and results of this adaptation are explained in this article. Since the distribution of phase/time is also gaining importance in telecom, the article briefly discusses the objectives, reasons, and upcoming work for the definition of another profile that will leverage other functions and clocks defined in IEEE1588.

Evolution of the standards for packet network synchronization

This article summarizes the work done by ITU-T Q13/15 over the last six years to standardize the transport of timing over packet networks. It provides a summary of the published documents in this area from ITU-T while providing some of the background that went into each document including the specification of synchronous Ethernet and IEEE 1588 telecom profiles. Finally, it provides insight into the future work on the transport of timing in packet networks in ITU-T Q13/15.

A Novel SDN-Based Architecture to Provide Synchronization as a Service in 5G Scenarios

Moving toward 5G, network synchronization is expected to play a key role in the successful deployment of the new mobile communication networks. This article presents an application of SDN (software defined networking) and NFV (network function virtualization) principles to the network synchronization area, making it possible to offer synchronization as a service. The approach is based on defining a harmonization layer that orchestrates radio and heterogeneous transport domains by means of a suitable subset of abstracted information exchanged among the domains, and by making use of virtualized synchronization functions.

SDN-based architecture to support Synchronization in a 5G framework

Network synchronization is expected to be one of the key aspects in 5G. This article presents an application of the SDN (Software Defined Networking) and NFV (Network Function Virtualization) principles to the area of the network synchronization, enabling to offer synchronization as a service. The approach is based on defining a harmonization layer that allows orchestrating radio and heterogeneous transport domains.

Synchronization standards toward 5G

The article in this special section focus on the development of synchronous standards for 5G mobile commuication services. These articles provide a first look at the synchronization directions toward 5G in terms of ongoing standardization efforts, standardization gap analysis, and potential solutions to close the gap.