IEEE Std 802.1CMde:2020 pdf download.IEEE Standard for Local and metropolitan area networks- Time-Sensitive Networking for Fronthaul Amendment 1: Enhancements to Fronthaul Profiles to Support New Fronthaul Interface, Synchronization, and Syntonization Standards.
6.3 Class 2 requirements
Change 6.3 as shown:
Class 2 refers to fronthaul interfaces where the functional decomposition of an E-UTRA BS (see 3GPP TS 36.104 [B 1]) or an NR BS (see 3GPPTS 38.104 [B3a1) into eRE and eREC is inside the radio physical layer (PHY) as specified by the eCPRI Interface Specification [B5]. eCPRI bit rates corresponding to the same end-user data rates are smaller than Common Public Radio Interface Specification [B4] bit rates due to the flexible functional decomposition provided by eCPRI. In the case of Class 2. the eCPRI protocol is used between the eRE and the eREC, and they are connected by a bridged network as described in Clause 8.
6.3.1 eCPRI background
Change the first paragraph of 6.3.1 as shown (text offiu#nole 19 remains unchanged.):
The eCPRI functional decomposition positions the split point inside the radio physical layer (PHY) when dividing a BS into eRE and eREC. The eCPRI Interface Specification [B5j functional split is more flexible than the Common Public Radio Interface Specification [B4j functional split. The fronthaul bridged network connects the eRE and the eREC regardless of the functional decomposition selected for a specific implementation. The intra-PHY splits introduced by eCPRI are called Split flD’TD;1U} (see 6.1.1 in the eCPRI Interface Specification V-l-42.O [B5]), which include multiple options.
change the last paragraph of 6.3.1 as slwwn:
When used for an E-UTRA or NR BS, eCPRI timing is related to the E-UTRA OFDMor NR frame structure and timing described in 6.1.
6.3.2 User Plane data requirements
Change the introductory text of 6.3.2 as shown:
This subclause describes Class 2 User Plane information flows and their requirements. The timing of the transmission of User Plane data by an eRE and an eREC is aligned with E-UTRA or NR OFDM timing (see 6.1), which is periodic. That is, the time windows when one or more packets of a User Plane data flow can be sent are aligned with the given OFDM timing. The traffic of a User Plane data flow carrying user data is correlated with the user data traffic of the corresponding UE (i.e., eRE and eREC exchange user data only when there is user data exchange between UE and BS). Thus, a User Plane data flow can have time windows with no packet. There is a maximum amount of data in a time window for a User Plane data flow. The requirements for User Plane data flows are described in the Requirements for the eCPRI Transport Network V1.2 [B6].
6.3.2.1 Latency
change 6.3.2.1 as showing:
The maximum end-to-end one-way latency is 100 for the majority of User Plane data bevcen an edge port connected to an eREC and another edge port connected to an eRE. This User Plane (fast) data belongs to the high priority traffic class in has the most stringent latency requirement according to Table I in the Requirements for the eCPRI Transport Network Vl.-l- [B6]. where this data belongs to the ‘High’ traffic class. Four latency classes for this data are specified for different use cases in Table IA in the Requirements for the eCPRI Transport Network V 1.2 [B6]. a subset of which is listed in Table 6-1.IEEE Std 802.1CMde pdf download.