1 Overview of 3G Packet Data Salih Ergut 7/16/2003

2 Outline cdma2000 packet data architecture and network elements Simple IP/Mobile IP Packet Network Nodes State Machines MAC Layer Packet Data Call Flows 1x EV-DV (1xRTT Evolution for high-speed integrated Data and Voice) Motivation, goals and basic principles

3 Packet Data Architecture BSC MSCPSTNVLR HLR PCF PDSN AAA Packet Network Telephone Network Home Agent Home AAA SS7 Network

4 Simple IP vs. Mobile IP Mobile station’s IP address will be changed as the subscriber moves to different cells Mobile station will be able to use a constant IP even when moving across different cells BSC PCF PDSN Packet Network BSC PCF PDSN

5 Mobile IP Registration Mobile registers its care of address HA replies with lifetime PDSN (FA) Packet Network Home AgentBSS MIP-RRQ MIP-RRP Packet Data Tunnel (UDP over IP)

6 Packet Network Nodes PCF (Packet Control Function) A required IP element in cdma2000 networks Provides relay to mobile from PDSN Keeps track of registration lifetime expiration and ensures that the sessions are renewed as necessary Controls the available radio resources Buffers data received from PDSN until radio resources becomes available Controls dormancy PDSN (Packet Data Serving Node) PPP datalink layer to mobile is terminated Interfaces with PCF IP packets are routed In MIP network acts as a FA

7 Packet Network Nodes AAA (Authentication, Authorization, and Accounting) Stores accounting information and authenticates/authorizes mobiles Provides security to FA and Foreign AAA. HA (Home Agent) Establishes a secure packet-data tunnel with the FA to provide MIP services and routes the packets destined to the mobile to the FA Authenticates MIP registrations

8 Assign Complete Mobile Originated Packet Data Call MSC PDSN BSC / PCF Origination Base Station Ack CMServReq SCCP-CC Assign Request TCH Setup A11-RRQ A11-RRP User Packet Data PPP Link Establishment and Mobile IP Registration A8 /A10 setup Packet Network UCSD Ericsson ///

9 Control Plane – Signaling BSC/PCFPDSN A11 UDP IP Link Phys A11 UDP IP Link Phys

10 User Plane – Relay Mode BSC/PCFPDSN RS-232 RLP RS-232 GRE AIR Inter- face RLP AIR Inter- face IP Link Phys End Host IP PPP A10 IP PPP IP Link Phys IP Link Phys GRE IP Link Phys

11 User Plane – Network Mode BSC/PCFPDSN RS-232 RLP RS-232 GRE AIR Inter- face RLP AIR Inter- face IP Link Phys End Host IP SLIP or PPP A10 IP PPP IP Link Phys IP Link Phys GRE IP Link Phys SLIP or PPP IP PPP IP

12 MAC States (1/3) Active Mode and DTX Data traffic flows Reverse pilot is not gated MS and BS can discontinue traffic for frames (~200ms) without tearing down traffic channel Control/HoldDormant secondminute Active FCH Active SCH millisecond

13 MAC States (2/3) Control Hold Triggered when the data traffic is idle ~1-2 seconds Signaling only Power control is maintained Reverse pilot can be gated MS Stores radio information Control/HoldDormant secondminute Active FCH Active SCH millisecond

14 MAC States (3/3) Dormancy Triggered when data traffic is idle ~1-2 minutes Traffic channels and A8 (BSC-PCF) connection is released A10 (PCF-PDSN) connection and PPP is maintained Control/HoldDormant secondminute Active FCH Active SCH millisecond

15 Dormant Mode Initiation BSC initiates when inactivity timer is expired or RF failure occurred MS initiates when inactivity timer is expired or TCH is released Reactivation Initiated when network or MS has data to send Since PPP is maintained no extra control plane signaling required User data is exchanged after reactivation

16 Inter BSC – Intra PDSN HHO MSCPDSN Source BSC/PCF HO Required HO Command User Packet Data HO Request HO Request ACK HO Commenced Target BSC/PCF HO Direction Msg Null Fwd Traffic Rev Traffic HCM Tear Down Channels Clear Command Clear Complete A11 RRQ (Lifetime = 0) A11 RRP A11 RRQ A11 RRP Handoff Complete User Packet Data

17 Quality of Service Still standardization is continuing Air interface is bottleneck for an end-to-end QoS Some parameters are defined such as User’s priority level (14 possible levels) Minimum acceptable data rate (2x, 4x, …) Acceptable FER (1%, 2%, 5%, 10%)

18 1x EV-DV (1xRTT Evolution for high-speed integrated Data and Voice)

19 Motivation CDMA 1x supplemental channel scheduling is slow (~2-4 secs) and data rate is not satisfactory (~144 kbps) Forward link has priority due to asymmetric nature of the data applications Flexibility against short term and long term voice and data demands

20 Design Goals Backward compatibility with cdma2000 1x cdma2000 1x features, applications and services and voice/data capabilities are maintained Minimal effect on the terminals and infrastructure for cdma2000 1x customers increase battery life as a side goal

21 Design Requirements FL peak data rate > 2.4 Mbps RL peak data rate > 1.25 Mbps Average throughput in FL and RL > 600 kbps Peak data rate and average throughput is at least as much as 1X EV-DO

22 What’s needed? Radio resources should be optimally used Radio link control & resource allocation must be optimized

23 How is it achieved? (1/3) 1x overhead Residual power for 1x EV-DV 1xEV-DV overhead Power for 1x voice and data Base Station Power 100% Time Packet Data Common Channel is introduced

24 How is it achieved? (2/3) Left-over power is used, hence no power control Rate control (higher order modulation and coding) is used to maintained link quality Optimally schedule delay tolerant data Favor the user with good channel quality Serve users both in parallel (CDM) and serial (TDM) while TDM is preferred if possible

25 How is it achieved? (3/3) Fast sector switching Fast channel quality indicator send by MS Fast physical layer ARQ (Automatic Repeat Request) which also provides error correction

26 What’s next? Reverse link data enhancements are necessary to meet the requirements, i.e Mbps Common services and mobility with different type of network access technologies, such as Wireless LANs, DSL, satellites etc.

27 4G Higher data rates ~2-20 Mbps New air interface needs to be developed Potential candidate OFDM Smart antennas can form directed beams to increase strength of the desired signal A new spectrum needs to be assigned Software radio can transmit over different air interface technologies All-IP vision: base stations become an access router