RNC_in_Pool.ppt
- 1. RNC in Pool Rose-Marie Friberg, SPM WCDMA RAN RNCin Pool
- 2. Scope › Background › RNC in Pool W14B › RNC in Pool W15 › RNC in Pool W16 › Summary › Typical User Case W14B
- 3. Background RNC 3820 EvoC EvoC EvoC EvoC RNC 3820 RNC 3820 RNC 3820 RNC 3820 EvoC EvoC › The trend is that RNS become smaller and smaller. – Increased Iur signalling. – Functionality not supported over Iur ie. IFLS & MC – Complex network – Larger RNC is a high risk
- 4. ReduceComplexity › RNC in Pool addresses both size of RNS as well as redundancy RNC 3820 EvoC EvoC EvoC EvoC RNC 3820 RNC 3820 RNC 3820 RNC 3820 EvoC EvoC
- 5. ONE RNS ONE RNS RNC 3820 EvoC RNCin Pool W14B Larger RNS,Iu/Iur Redundancy
- 6. Iu/Iur redundancy RNC 1 FE BE FE BE BE RNC 2 BE BE BE INC RNC 3820 EvoC /RNC Iu/Iur Iub Iub FE FE FE FE RNC Node Cluster One RNC ID Requirement on RNC 3820: › Only GPB75 can be used (RNC 3820 R1.1 or R2) › FAJ 121 1670 Dynamic Iu/Iur signaling implemented
- 7. One Linkset • Round-robin algorithm on these associations towards RNC. • If any link is down the others will take the traffic. RNC in Pool
- 8. RNC Node 2 RNC Node 1 RBSrehoming Today Iub MC 1.x Current Allocation cell Iub Link Iub Link cell MC 2.z New Allocation cell Iub Link Iub Link cell Re-home RBS affects all cell relations (HO) in WCDMA/LTE/GSM networks – The change of Cell identity affects all neighboring cells – The change of Cell identity make it difficult to track traffic evolution Old Cell Id New Cell Id
- 9. RNC Node 2 RNC Node 1 RBSrehoming First stepin Cluster Iub MC 1.x Current Allocation cell Iub Link Iub Link cell MC 2.z New Allocation cell Iub Link Iub Link cell RNC Node Cluster Re-home RBS within cluster is almost a “re-module RBS” – Easy to move RBS between cluster members due to no change of Cell id – No impact on other traffic nodes (Iu/Iur, cell IDs, cell relations etc.) Step 1: Manual lock/unlock of Iub links for load balancing or maintenance Old Cell Id Old Cell Id
- 10. Connectivity GSM/WCDMA/LTE Mobile backhaul Mobile Core Switch Switch BSC RNC RNC MGW SGSN /MME MSC GGSN/ P/S-GW AGW RNC pool RNC Switch Site router router router router router router › Propagation delay: 4 ms › Delay variation: 5 ms › Packet Loss: 10-3 › NodeB Mix of ATM and IP › All other interfaces on IP › 10G interface for Iux
- 11. Handover between 2 cells SP Node Cluster CM1 CM2 ctxt LmCell LmCell User Plane Control Plane IP-ET IP-ET Iux On Iux: › The control signaling needed to add a cell and getting the cell information from the other Cluster Member. › When the CM1 gets the RBS IP address an IP host is chosen and an IP path is set to the RBS controlled by CM2. All User Plane traffic will use this path. › User plan does not pass the other RNC. On Iur: › Both control plane and User plane goes over Iur to the other RNC.
- 12. ONE RNS ONE RNS EvoC EvoC RNC 3820 EvoC RNCin Pool W15-W16 Iub LinkRedundancy, 2EVO Controllers
- 13. RNC Node 2 RNC Node 1 Iub LinkRedundancyW15B Iub/IP Redistribution of IubLink/cell to secondary allocation MC 1.x Primary Allocation cell Iub Link Iub Link cell MC 1.y Secondary Allocation cell Iub Link Iub Link cell MC 2.z Secondary Node Allocation cell Iub Link Iub Link cell MC 2.w Primary Allocation cell Iub Link Iub Link cell Iub/ATM RNC Node Cluster Same Cell Id
- 14. ONE RNS RNCin Pool W16 Larger Clusters,Iub Link Balancing
- 15. RNC Node Cluster Load Balancing on Pool level Load Balancing on Node level Cell Load Iub LinkBalancing W16 Rejection margin RNC 1 RNC 2 RNC 3 RNC 1 RNC 2 RNC 3
- 16. › RNC in Pool W14B support easy capacity increase by adding new EvoC to existing RNC 3820 – Without adding new RNS – Iub redundancy can be achieved by using scripts › RNC in Pool W15A support easy capacity increase by adding new EvoC to existing EvoC › RNC in Pool W15B to add automated redundancy for Iub links › RNC in Pool W16 to automate load balancing over the pool › RNC in pool will simplify network – less RNS Summary
- 17. TypicalUse CaseW14B › A large number of RNC 38x0 RNC 3820 RNC 3810 RNC 3820 RNC 3820 RNC 3820 RNC 3810 RNC 3820
- 18. › Add an EvoC in pool with existing RNC 3820 – No new RNS – no impact on Core network RNC 3820 RNC 3810 RNC 3820 RNC 3820 EvoC RNC 3820 RNC 3810 RNC 3820 TypicalUse CaseW14B
- 19. › Add an EvoC in pool with existing RNC 3820 – No new RNS – no impact on Core network › Re-home RBS to pooled RNS RNC 3820 RNC 3810 RNC 3820 RNC 3820 EvoC RNC 3820 RNC 3810 RNC 3820 TypicalUse CaseW14B
- 20. › Add an EvoC in pool with existing RNC 3820 – No new RNS – no impact on Core network › Rehome RBS to pooled RNS › Reduce no of RNC RNC 3820 RNC 3820 RNC 3820 EvoC RNC 3820 TypicalUse CaseW14B
Editor's Notes
- #2: 1
- #3: 2
- #7: The pool members work as peers and both nodes take and execute Iu/Iur traffic. Iu/Iur redundancy is achieved by that all RNC in the Pool get the same RNC id. With the feature Dynamic Iu and Iur Signaling (FAJ 121 1670) in both nodes the Signaling Front Ends will act as one signaling destination point code. The prerequisite on the RNC 3820 is that all GPB’s are GPB75 and that the Feature FAJ 121 1670 Dynamic Iu and Iur signaling is implemented. This feature is default in EvO Controller 8200. Since they have the same RNC id the connection toward the Core is the same as for a single RNC today. The difference is that its a bigger node with more physical links. MSC and other nodes sees the pool as one node / RNS. OSS see the 2 RNC’s as 2 nodes but they have the same RNC id and share the neighboring cells. The existing grouping mechanism in OSS common Explorer will be used to visualize the node cluster. It will be possible to add RNC nodes to an OSS group a.k.a. cluster.
- #8: By defining the same RNC id and Signaling destination point code in both nodes the links will act as one linkset where a round robin mechanism will send 1/3 of the traffic to the RNC 3820 and 2/3 to the Evo Controller 8200. If any of the links are down the other lin.ks in the linkset will even share the traffic
- #9: Re -homing of a RBS today means that all cells will change Cell identity. That will affect all neighboring cells as well as the data up in the Core Network.
- #10: Re-homing between the Pool members means that the cell will keep its identity even if the Iub link is moved to the other RNC. That means no impact on other nodes outside the pool and no impact on the cell relations. This simplifies if Iub links needs to be moved to better balance load between the pool members. Iub link redundancy can be achieved by defining same Iub link, cell and cell relation data in both RNC's and then use scripts to fast unlock/lock the Iub links.
- #11: The Iux interface is replacing the Iur interface between the pool members. Iux is an internal interface and set up by using normal VLAN functionality and connected via site routers. The requirement on the Iux interface is the same as for the Iur interface regarding delay and delay variation. That means that the RNC’s in the pool can be geographic separated as long as a god QoS can be provided.
- #12: Iux is used for control signaling between the pool members. The user plan is not moved when a handover is made to a cell in the other pool member. So no user data is sent over Iux which means that traffic over Iux is reduced compared to over Iur.
- #14: The automated Iub redundancy means that Iub link, cell and cell relation data automatic will be synced between the pool members. If one RNC fails that triggers the other RNC to unlock the Iub links that belonged to the failing RNC. This feature do not require any changes or have any impact on the RBS. Since already from the beginning both RNC are sean as one with one RNC id from the RBS side. A RNC failure will be seen as a short drop of contact on the RBS side.
- #16: The cell load balancing mechanism automatic distribute IP/Iub links over the pool to get optimal performance and simplify management. Constant monitoring is made on the RNC's cell load and a warning will be issued when a threshold is reached and rebalancing is needed The re-balancing based on latest monitored data will be made on a regular basis or when a threshold is reached. It is made by lock/unlock RBS (Iub links) between boards or between nodes. This means that the nodes will adept to changes in the traffic over time. The ATM based Iub links is part of each nodes load balancing calculations and can be reallocated within each node but not between. That means that in case of a complete node failure they will not have redundancy.
- #17: RNC in Pool W14B support easy capacity increase by adding new EvoC to existing RNC 3820 - Without adding new RNS - Iub redundancy can be achieved by using scripts RNC in Pool W15A support easy capacity increase by adding new EvoC to existing EvoC RNC in Pool W15B to add automated redundancy for Iub links RNC in Pool W16 to automate load balancing over the pool RNC in pool will simplify network – less RNS
- #22: 21