140010074-Cell-Broadcast-Service-in-Ericsson-RAN-P7.pptx

140010074-Cell-Broadcast-Service-in-Ericsson-RAN-P7.pptx

1. Cell Broadcast Service in RAN P7

2. Overview

3. FAJ 121 1326 Cell Broadcast Service P7 Feature Scope (Optional) Enables broadcast of short text messages to UEs in idle mode and URA_PCH state CB messages are generated by an external Cell Broadcast Centre (CBC) and sent to UTRAN via the new Iu-BC interface. Uu RRC: SIB5 BMC signalling (25.324) Logical ch: CTCH Transport ch: FACH1 Physical ch: S-CCPCH Iu-BC SABP signalling (25.419) Signalling transport (25.414) TCP/IP (port: 3452) IP or ATM transport

4. Concepts Cell Broadcast (CB) message User data as transmitted from the CBC to the UE Cell Broadcast Service Area (CBSA) A CBSA represents the smallest geographical area where CB messages can be broadcast. One CBSA contains one UTRAN cell BMC CB message BC CB messages are sent from WCDMA RAN to the UE using the BMC protocol. A BMC CB message contents one CB message CTCH occasion A radio frame on the S-CCPCH where CTCH can be sent

5. CBS in Ericsson RAN P7 (1/2) Restrictions & Limitations CBS Level 2 Scheduling (DRX mode) is not supported in P7 Max CB messages stored per cell: 20 Max CBS payload stored per cell: 2.5 kbyte References CPI: Cell Broadcast Service, 126/1553-HSD 10102/7 3GPP SoCs: BMC (25.324), 44/17402 - HSD10102/7 SABP (25.419), 45/17402 – HSD 10202/7 Iu interface data transport & signalling (25.414), 02/17402 – HSD 10102/7

6. Feature preparation CN requirements: None Hardware requirements: R4 HW for the RANAP/RNSAP MP in RNC UE requirements: Support for CBS according to 3GPP Rel-99 Initial tuning: Not applicable Feature Activation SW license for FAJ 121 1326 installed and activated in RNC MO IuBcLink created and unlocked Cell Broadcast Service Area defined per UtranCell (parameter cellBroadcastSac ) Note: Activation of this feature will impact UE battery consumption in idle mode and state URA_PCH CBS in Ericsson RAN P7 (2/2)

7. Radio Protocol

8. BMC protocol model & functions Storage of Cell Broadcast Messages Scheduling of BMC messages Transmission of BMC messages to UE Note : E/// P7 will not support Traffic volume monitoring and radio resource request Functions

9. Cell Broadcast Service Area CBSA (Cell Broadcast Service Area) definition PLMN id + Location Area Code (LAC) + CB Service Area Code Only used towards the CBC and contained one cell CB SAC is configured in RNC and set as cellBroadcastSac OSS provide consistency check rule To verify CBSAs are unique in all the network Existing SA towards CN (CS and PS domain) is not affected.

10. Start of CBS operation Criteria to start CBS operation The CBS feature activated and the license is loaded The Iu-BC link is configured The cells in which CB messages are to be broadcast are enabled and a CBSA is defined for each cell RNC send a SABP RESTART message to CBC Contains a list of all defined CBSAs within the RNC. SABP RESTART Message is also sent When Disable cell was recovered and trigger to the RNC And periodic timer of 30seconds is expired Timer is implemented to avoid frequent messages Message contains a list of all CBSAs that have triggered within last 30second

11. Broadcasting the message (Write and Replace) Note: E/// P7 doesn’t support BMC schedule message

12. Write-Replace Message from CBC (1) Message type Identify the type of message (e.g. Write-Replace) Message identifier RNC uniquely identify the CB message by this identifier with the 12 left most bits of the Serial number New serial number and old serial number Indicate new and old message Service Area identifier Identifies Service area Max 2304 Service Areas are supported Category “High priority” : Broadcast immediately “Background” : Broadcast when No High priority or Normal Traffic broadcast “Normal” : Broadcast according to the repetition period IE Note : In Ericsson’s implementation RNC will not use the Category information. All CB messages are sent immediately after reception of a Write-Replace message.

13. Write-Replace Message from CBC (2) Repetition Period Indicates the periodicity of message broadcasts Set from once per one second to once per -1 hour Number of Broadcast requested Indicates the number of the times a message to be broadcast 0 – 65535: 0 indicates “until other command received from CN” Data Coding Scheme Identifies the alphabet or coding employed for the message characters and message handling Broadcast message content Bit string (1….9968) ,,, The size shall be multiple of 8

14. Write-Replace RNC action Checks all service areas are defined as CBSA then responds Write-Replace complete message If not, responds Write-replace failure message If the cell contained in the CBSA is enabled The new message is stored If the Message contains old serial number The previously stored message replaced with the new message New message is broadcast on CTCH With the repetition period requested by CBC For infinite Broadcast the CB message is repeated until it is deleted by CBC

15. Deletion of CB messages Kill Procedure Used to stop broadcast of one CB message in one or several CBS’s Reset Procedure Used to stop broadcast of all CB messages stored in one or several CBS’s

16. CTCH mapping on S-CCPCH The logical channel CTCH is multiplexed on FACH1 Then carried by exiting S-CCPCH for 32kbps Interactive PS RB and SRB’s The CTCH is scheduled on S-CCPCH during predefined CTCH occasion i.e. timing of CTCH transmission is fixed CTCH SFN 0 CTCH SFN N SFN 1 S-CCPCH ctchOccasionPeriod ...... 10mS SFN 2 ...... SFN N+1 SFN cycle : 0…..4095

17. CTCH Occasions CTCH occasions are defined as SFN=K+m*N, m=0,1,2….M K: Offset of the first CTCH, Hard coded to 0 N: Period of CTCH occasion, ctchOccasionPeriod:1-256 M: Chosen so that SFN=K+m*N <=4095 (Max SFN) SFN cycle : 0…..4095 CTCH SFN 0 CTCH SFN N SFN 1 S-CCPCH N: ctchOccasionPeriod ...... 10mS SFN 2 ...... SFN N+1 Maximum BW of CTCH Channel can vary from 0.18kbps to up to 30.4kbps

18. CTCH occasion impact Impact on SRB and PS interactive, UE power consumption BMC CB messages will have the highest priority in frames defined as CTCH occasions Other FACH1 or FACH 2 data can be sent if no CTCH data Frequent CTCH occasion and high CBS load cause delay of SRB and PS interactive on FACH 1 and FACH2 UE (In idle and URA_PCH) must listen to every CTCH occasion Trade off between Max CTCH BW and UE power Consumption Need to select CTCH occasion period carefully Confliction with paging occasion UE will prioritize paging occasion if paging occasion conflict with CTCH occasions in idle and URA_PCH state Paging occasions are calculated based on the IMSI and the DRX cycle length coefficient Need to make sure CTCH occasion period is not set to a multiple of DRX cycle length coefficient to avoid same UE will miss CTCH occasion

19. IuBC Interface

20. Iu-BC protocol stack and precondition The Iu-BC interface is standardized by 3GPP . The CBC node must be connected to the O&M IP network The O&M IP network must allow the TCP port for SABP 3452 and will compete for bandwidth with the O&M traffic IP Iu-BC protocol stack ATM Iu-BC protocol stack

21. Iu-BC using ATM transport Iu-BC and O&M traffic will share the same IP host in RNC. For ATM case , Iu-BC traffic is carried to O&M router using ATM . The CBC node must be connected using IP/Ethernet to O&M Router. IP transport (Iu-BC) ATM transport (Mur + Iu-BC)

22. Iu-BC using IP transport For IP case Iu-BC can be carried over IP/Ethernet straight to the CBC node from RNC all IP Routing configuration in RNC for Mur can be reused for Iu-BC as the Iu-BC interface is connected to the same O&M IP network as Mur. There is no need to add or modify routes as all traffic is sent to the O&M Router. IP transport (Iu-BC) IP transport (Mur + Iu-BC)

23. QoS From RNC to CBC node the Iu-BC traffic will get the same QoS characteristics as O&M traffic. For the traffic from the CBC to the RNC, QoS separation in the IP network using different settings of the DSCP (DiffServ Code Point) can be done if the CBC node supports it. The QoS characteristics currently recommended for O&M traffic is assumed to be adequate for Iu-BC traffic. An operator may choose to implement an O&M IP network with a higher QoS level.

24. Dimensioning The dimensioning of the O&M IP network should take into account Iu-BC traffic. The Iu-BC traffic volume is expected to be low and the impact on the dimensioning should be small. The Iu-BC capacity demand can be calculated using the formula below: C Iu-BC = Msglength * numMsgs/second Msglength is the length of the SABP message. Note that the maximum length of a SABP message that can be processed in WCDMA RAN is limited to 18000 octets. numMsgs/second is the number of SABP messages sent over the Iu-BC interface per second.

25. O&M Network (IP) RNC3810 <Network example> ET-M4 O&M Router <ATM/IP Converter> Mur OSS Server CBC Network (IP) CBS Core MP Backplane

26. Mur O&M Network (IP) RNC3810 <Network example> ET-M4 O&M Router <ATM/IP Converter> Mur OSS Server O&M Router X Core MP Backplane CBC Network (IP) CBS

27. Redundant example with ET-MFX ET-MFX board redundancy

28. Some Iu-BC Network Example IuBC Host IuBC Host IuBC Host IuBC Host IuBC Host IuBC Host CBS NW Address Translation NW Address Translation Area 1 Area N

29. O&M

30. New/Modified MO structure

31. Each UtranCell can be associated with a new Cell Broadcast Service Area used towards the CBC node. SAC for the CB SA is set by parameter cellBroadcastSac Existing SA towards CN (CS and PS domain) is not affected. Parameter setting (1/3) cellBroadcastSac

32. Scheduling of CTCH on S-CCPCH is controlled by parameter ctchOccasionPeriod. The setting of ctchOccasionPeriod is a trade off between max CBS throughput and UE battery usage in idle mode and URA_PCH state. ctchOccasionPeriod CTCH CTCH S-CCPCH ctchOccasionPeriod ...... Parameter setting (2/3)

33. cbcIpAddress Four field of digits, separated by dots. Each field may consists of three digits. The value of each field shall be in the range 0….255 sourceIpAddressValidation Filter for IP source address validation in the RNC If it set to “true” filter will avoid the establishment of connections from other IP addresses Parameter setting (3/3)

34. No impact on KPIs New pm counters pmNoReceivedSABPMsgs : Number of received SABP messages over Iu-Bc pmNoSentSABPMsgs : Number of sent SABP messages over Iu-Bc pmNoRejectedTcpConnections : Number of rejected TCP connections because of disallowed source IP address pmNoDiscardedCbsMsgOrders : Number of discarded CB message orders per cell pmNoDiscardedBmcMsgs : Number of discarded BMC PDU’s per cell. Each BMC PDU contains one BMC CB message. pmBmcTrafficVolume : Accumulated BMC payload (bytes) per cell Observability (1/2)

35. New GPEH events CBS_MESSAGE_ORDER_DISCARDED – triggered each time counter pmNoDiscardedCbsMsgOrders is stepped. New events for all SABP messages transmitted over Iu-BC: SABP_WRITE_REPLACE SABP_WRITE_REPLACE_COMPLETE SABP_WRITE_REPLACE_FAILURE SABP_KILL SABP_KILL_COMPLETE SABP_KILL_FAILURE SABP_RESET SABP_RESET_COMPLETE SABP_RESET_FAILURE SABP_RESTART SABP_ERROR_INDICATION Observability (2/2)