Integration of Sidelink Procedures

in OAI (ProSe Applications) 21/06/2018

Overview of this talk

Background

Objectives

Overview of LTE Sidelink Scenarios

Integrated Features

Next steps

(c) Eurecom 2018

Background

OAI sidelink work is done in the context of the DDPS project – USA NIST project framework program (PSISP)

– Aims to promote LTE technologies for public-safety network, including ProSe Sidelink (PC5) technology demonstrators

– Project coordinator: PerspectaLabs (New Jersey), Dr. Richard C. Lau

– Team members at PerspectaLabs

William Johnson

Heechang Kim

Stephanie Demers

James Hodge

Eric Beck

– Team members at EURECOM

Panagiotis Matzakos

Tien-Thinh Nguyen

Raymond Knopp

Jerome Haerri

(c) Eurecom 2018

OAI Objectives

Integration of Rel 14 Sidelink procedures (L1/L2)

Integration of Rel 14 CN procedures in support of ProSe and UE-Network Relay

Interfaces for ProSe applications in UE

Testing – ProSe application from PerspectaLabs

– Small field deployment with OAI-based UEs and Infrastructure

(c) Eurecom 2018

Side link, SC-FMDA, FDDCellular LTE

in-networkProSe (PC5)

Off-networkProSe (PC5)

Partial-in-networkProSe (PC5) eNB

ProSe Function

EPCS1

PC3

Uu

UE-Network Relay

PC4PC2

ProSeAppl Server

Scenarios

on-network coverage

– Regular LTE Iu-interface communications

off-network coverage

– PC5 interface

partial coverage.

– UE-to-network relay procedures

New Communication modes support

– one-to-one

– one-to-many direct communication.

(c) Eurecom 2018

High-level Software Architecture

(c) Eurecom 2018

OAI extensions for ProSe

PC5-D: The discovery plane of PC5 interface is needed for direct discovery. Discovery allows a UE to discover other UEs that are in proximity. The ProSe Protocol interacts directly with the MAC layer

PC5-S: The PC5 signaling protocol stack is used for control plane signaling over the PC5 interface to establish, maintain, and release a secure direct link between two UEs.

PC5-U: The user plane PC5 interface is used to send traffic directly between two UEs. A UE may establish multiple logical channels, which is not show in Figure 3. A logical channel ID (LCID) included within the MAC subheader uniquely identifies a logical channel within the scope of one Source Layer-2 ID and ProSe Layer-2 Group ID combination. Note that in our OAI ProSe implementation, the IP tables are responsible for IP to sidelink radio bearer (SLRB) mapping. The UE_ip.ko kernel module uses the information provided by the IP tables in order to route each ProSe flow to the right SLRB.

PC3: The control plane PC3 interface is used for service authorization between the UE and the ProSe Function when the UE is connected to the network (i.e., on-network). The ProSe control signaling is carried over the LTE user plane (i.e., LTE-Uu, S1-U, S5/S8 and SGi) Note that the PC3 interface is not used when the UE is off-network. In the off-network case, service authorization is pre-configured in the UE.

(c) Eurecom 2018

OAI ProSe Extensions

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L1 features

PC5 Synchronization

– Implementation of SynchRef UE (SPSS,SSSS,PSBCH)

– Implementation of synchronization and tracking procedures for

off-network UEs

PC5

– Implementation of TX/RX procedures for PSSCH/PSCCH

(c) Eurecom 2018

Integration Testbed

(c) Eurecom 2018