Market Overview

xRAN Forum Releases Second Open Fronthaul Control, User and Synchronization Plane Specification and First Open Fronthaul Management Plane Specification


The xRAN Forum (xRAN) today announced the Board's approval and public
availability of the xRAN Fronthaul Control, User and Synchronization
(CUS) Plane Specification Version 2.0 and the xRAN Fronthaul Management
Plane (MP) Specification Version 1.0. The specifications have been
designed to allow a wide range of vendors to develop innovative,
best-of-breed RRUs and BBUs for a wide range of deployment scenarios,
which can be easily integrated with virtualized infrastructure &
management systems using standardized data models.

The new specifications deliver on important operator member
requirements. All xRAN operator members extend well deserved credit and
gratitude to the xRAN members who made contributions and facilitated
strong collaboration within the xRAN Forum Front Haul Working Group,
chaired by Verizon Communication.

The xRAN Forum fosters a growing ecosystem of innovative and
interoperable RAN products catering to the varied needs of the Forum's
operator members. Interfaces defined by the xRAN Fronthaul Specification
enable efficient deployment of advanced technologies like Massive MIMO &
Virtualized RAN with support for LTE and NR.

The second major version of CUS-plane specification incorporates several
enhancements over the first version including:

  • Support for 2 radio categories (A and B) to enable both simple and
    more complex functionality leveraging largely the same interface
  • Additional compression modes to provide increased fronthaul bandwidth
  • Support for critical items such as synchronization and timing to
    enable commercialization and interoperability in deployments
  • Support for additional LTE system features like LAA, NB-IOT, including
    improved efficiency in parsing of U-plane packets

The first version of M-plane specification is a significant milestone
for the industry. It provides an open multi-vendor M-plane model for
radios based on standardized modern protocols like NETCONF/YANG and
includes key capabilities:

  • Support for features and capabilities in v1.0 of CUS specification and
    several enhancements in v2.0 of CUS specification
  • Flexible management architecture providing support for traditional
    hierarchical and hybrid (multiple NETCONF clients or EMS can directly
    communicate with radio) deployment models
  • A comprehensive YANG model developed for 4G & 5G radios building upon
    industry accepted data models

A registration link to download the complete specifications is available
on the xRAN

About xRAN Forum

The xRAN Forum was formed to develop, standardize and promote an open
alternative to the traditionally closed, hardware-based RAN
architecture. xRAN fundamentally advances RAN architecture in three
areas – decouples the RAN control plane from the user plane, builds a
modular eNB software stack that operates on common-off-the-shelf (COTS)
hardware and publishes open north- and south-bound interfaces to the

Since its founding the xRAN Forum has gained tremendous industry
momentum with leadership from operators AT&T, Deutsche Telekom, JIO,
KDDI, NTT DOCOMO, SK Telecom, Sprint, Telefonica, Telstra and Verizon.
At the same time, xRAN has grown its contributing member base with
strong representation from the vendor community including: Altiostar,
Amdocs, Aricent, ASOCS, Blue Danube, Broadcom, Ciena, Cisco, Commscope,
Fujitsu, Intel, Keysight Technologies, Mavenir, NEC, Netsia, Nokia,
Pivotal Commware, Radisys, Samsung, Stanford University, University of
Sydney, and VIAVI Solutions

For more information about xRAN Forum membership go to
or email

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