specification for the key internal interface of radio base stationsbetween the Radio Equipment Control (REC)
and the Radio Equipment (RE). The parties cooperating to define the specification are Ericsson AB, Huawei
Technologies Co. Ltd, NECCorporation, Nortel Networks Ltd, Alcatel Lucent and Nokia Siemens Networks
GmbH & Co. KG.
Motivation for CPRI:
The CPRI specification enables flexible and efficient productdifferentiation for radio base stations and
independent technology evolution for Radio Equipment (RE) and Radio Equipment Control (REC).
Scope of Specification:
The necessary items fortransport, connectivity and control are included in the specification. This includes
User Plane data, Control and Management Plane transport mechanisms, and means forsynchronization.
A focus has been put on hardware dependent layers (layer 1 and layer 2). This ensures independent
technology evolution (on both sides of the interface), with a limited needfor hardware adaptation. In addition,
product differentiation in terms of functionality, management, and characteristics is not limited.
With a clear focus on layer 1 and layer 2the scope of the CPRI specification is restricted to the link interface
only, which is basically a point to point interface. Such a link shall have all the features necessary toenable a
simple and robust usage of any given REC/RE network topology, including a direct interconnection of multiport
Redundancy mechanisms are not described in the CPRIspecification, however all the necessary features to
support redundancy, especially in system architectures providing redundant physical interconnections (e.g.
rings) are defined.