IEEE 1914.3-2018 pdf download
IEEE 1914.3-2018 pdf download.IEEE Standard for Radio over Ethernet Encapsulations and Mappings.
5.3.3 RoE mapperslRoE de-mappers
An RoE mapper is a function/process that converts other transport framing formats to an RoE framing format, and an RoE de-mapper performs the opposite function. This specification describes different flavors of RoE mappers. Structure-aware and native RoE mappers separate control data and sample data into different channels. Control data is fed to a block known as the “control process” in this specification (see 8.3.4). On the RoE de-mapper direction, the RoE control packets received by the control process are fed to RoE demappers with the .flowlD set to ALL_ONES flowiD and the .deMapperlD set to appropriate values by the control process. The chief function of an RoE mapper is to select the appropriate input data from the input data stream (e.g., a CPRI port) and then packetize it. The RoE mapper also generates or selects control information. Individual subclauses in this specification describe the operation of RoE mappers and RoE de-mappers.
The RoE mapper is responsible for generating the ordering information. The functionality of the ordering information is described in 5,5.5.
Structure-agnostic RoE mappers do not have control packets because the entire data stream (including control information) is encapsulated as a single LCD data channel.
5.3.4 CPRI ports
CPRI (or CPRI-like) ports are physical connections. In structure-aware and structure-agnostic mapping modes,
an RoE node has CPRI (or CPRI-like) ports. CPRI (or CPRI-like) ports are assumed to be bidirectional.
5.3.5 subType mapping object
The subType mapping object is a table used to maintain and assign mapped subTypes (as specified in Table 2) from the RoE subtype space to particular organizationally unique identifier (OUI) or company identifier (CID) entities and their specified subType/payload structures. RoE nodes process mapped subTypes, the corresponding payload structure, and optional reserved bits in seq Nuni as specified by the OUI or CID entity. OUI or CID values are obtained through IEEE registration. An implementation can pre-populate the mapping table with implementation-specific default values. UnusedJun-mapped OUI/CID subTypes are indicated by setting the .niapSubtype bits 15 to 0 to ALL_ONES.
Table 2—subType mapping table
While the length field is 16 bits, the 2 MSBs are reserved for future use by this standard. Until any further
definition is available, they shall be set to 0 on transmit and ignored upon receipt.
5.5.5 Ordering information (orderlnfo)
5.5.5.1 General
Ordering information is assigned to each flow and is presented in one of two methods: a sequence number or tirnestamp. The orderlnfo type used for a given flow is determined by a parameter. This parameter is described in Table 10 and Table 11. This parameter shall be maintained throughout the lifetime of the flow. For data packets, the orderinfo value is the sequence number or tirnestamp that applies to the start of the RoE payload data (not counting RoE fields such as rbMap, see Figure 18).
5.5.5.2 Sequence number (seqNum) field
The sequence number field is used to identif’ the order of successive packets. To allow additional flexibility, it is possible to have two independent counters, e.g., one for hyper-frame number (HFN) and another for Node B frame number (BFN).
The sequence number field is generated by the RoE mapper and consists of three independently sized fields, whose sizes depend on two variables,p and q. The bits p up to and including 31 constitute the p-counter field and the bits q top—I constitute the q-counter field.
Figure 9 illustrates the composition of different fields that together form the sequence number field. The following rules shall apply:
The other two fields may exist based on the p and q values. Each RoE flow that uses sequence numbers shall have its own instance of p-counter and q-counter. Each of the fields is initialized to a known value on the first use of the sequence number. Note that the .seqNuniPMax, .seqNurnPlncProp, .seqNumQNlax, .seqNumQlnc, .seqNumQlncProp, and .seqNurnRsvd values shall remain unchanged during the lifetime of the RoE flow; but each flow may have different values for these parameters.
