ETRI Proprietary-1-

Layer 2 Mobility for Real Time Packet Data Service in All IP

Network3GPP2 All IP Ad Hoc

Boulder, COJuly 17~19, 2000

E T R I

Jae-Young Ahn , Kyung-Sik Kim, Sang-Ho Choi

Phone : + 82-42-860-3817

E-mail : jyahn@nice.etri.re.kr

ALLIP-20000717-036

ETRI Proprietary-2-

Background

▣ Motivation◈ In current 3G cdma2000 Packet Data Service Reference Model(PN-4286), Da

ta Link Layer(PPP or HDLC) should be reestablished in case of changing serving PDSN(Mobile-IP FA)

– It results serious degradation or interruption of service

◈ TSG-P already suggested the need of simple link layer protocol with the following properties: (P00 20000605-010, Qualcomm)

Simplicity in protocol and with minimal state Improved data transparency (minimize byte escaping, bit stuffing, etc.) Low header overhead on the transport QoS support Negotiation of compression (header and/or payload)

Protocol should be extensible

◈ As long as 3GPP2 All IP is highly related to PN-4286, All IP AdHoc is also required to investigate the feasibility of new link layer protocol improving L2 mobility not in PN-4286, but in All IP Network

ETRI Proprietary-3-

L2 Mobility in All IP MM domain

▣ PS domain in All IP Network experiences more serious problems on L2 Mobility because of temporal attribute of multimedia service ◈ Serious burst data loss in case of time-sensitive application(e.g. packetized Serious burst data loss in case of time-sensitive application(e.g. packetized

Video or Voice)Video or Voice)

◈ Resource waste due to retransmission and large buffer due to congestionResource waste due to retransmission and large buffer due to congestion In case of Best-effort Application (e.g. simple data )In case of Best-effort Application (e.g. simple data )

▣ No Contribution about Layer 2 (L2) mobility in All IP AdHoc

▣ L3 Mobility could be deleted or restructured because of its potential redundancy between L2 and L7 mobility◈ L2 is becoming a bottleneck in view of handoff performance

▣ Focusing on L2 Mobility concerned with All-IP Requirements◈ Use of PPP in All IP network protocol based on current 3GPP2 All IP NAM i

s to be problematic along with the progress of All IP standardization

◈ Specially unsatisfied results on Editor’s Accepted(Revised) Requirement Items in case of handoff (e.g. No interruption of service , etc.)

ETRI Proprietary-4-

Possible types of MS in All IP Network

▣ Assume that there are:

◈ Type 0 MS– 2G cdma MS

◈ Type I MS– 3G cdma2000 MS

CS Voice and Image PS Packet Multimedia Data( Packetized voice, image and data)

◈ Type II MS– Pure All IP Multimedia MS (Wireless SIP or H.323 VoIP)

PS Multimedia data(Packetized Voice, Image and Data) => RTP/UDP/IP

ETRI Proprietary-5-

L2 Mobility of MS Type I

▣ Use of PPP for link layer between MS and PDSN◈ In hand-off between PDSNs, require PPP reestablishment

◈ Real time packet data => Intolerable data loss– In Current cdma2000 System for packet data => No solution

◈ Best-effort Application => Needs retransmission and sufficient buffer

◈ Complex Header Compression due to PPP frame format and Various RLP Instances

▣ Evaluation◈ Insufficient capacity for Real-time Multimedia services

– Only usable for simple packet data service

◈ Only one detour depending on PDSN coverage planing– PDSN capacity is to be the major hurdle

– Depending on operator’s policy

ETRI Proprietary-6-

L2 Mobility for MS Type II

▣ Upgrade of link layer protocol means a room for upgrading L2 Mobility for All IP

▣ Use of PPP for All IP Network means the easy migration from 3G legacy network but the same problems are remained

▣ Improve of L2 Mobility by using non-PPP protocol is required to support real-time multimedia service ◈ Advantage

– Possible smooth and fast handoff for real time packet data

◈ Disadvantage– It may need the modification of the air interface protocols

– It may need authentication procedure instead of CHAP extension

– It may need modification of TR45.6 functions

– Needs the increased cost for evolution

ETRI Proprietary-7-

Smooth Handoff Aspect on Type II MSs

▣ Using PPP ◈ Need of MS which can control multiple PPP session for the support of

function similar to soft handoff

◈ Need of the solution for complex header compression

▣ Using non-PPP◈ Need of new protocol for Type II MS and network entities

◈ Need of new solution for loose header compression

ETRI Proprietary-8-

Conclusion

▣ Justification ◈ upgrading L2 mobility results improvement of handoff performance consistent w

ith Lucent contribution (ALLIP-20000717-020) “requirement sec. 6.1.9.Mobility Management”

– (e.g. Access Network Mobility with no service interruption)

◈ In order to support real-time service in All IP, L2 Mobility protocol should me improved as well as L7 and L3 Mobility management

– L3 MM functionality can be controlled in conjunction L2 upgrade, since L3 MM has potential redundancy in IP MM domain

▣ Conditions for further improvement◈ Handoff performance of the new protocol for L2 mobility should be enough to s

upport QoS requirement for real time service including packetized video and voice

◈ Reliability for real time packet data is to be improved as well

ETRI Proprietary-9-

Suggestions

▣ CRs to 3GPP2 All IP Ad Hoc Requirement v0.4.0◈ In section 6.2.1 , add item b)” The all-IP network IP MM domain should sup

port link layer handoff for real-time multimedia, in a way of maximizing handoff performance

◈ In section 6.3.4 , correct item d)”The All IP Network IP Multimedia domain shall support hard handoff between two RANs of the same technology, by means of L2 mobility

◈ In section 6.3.4 , add item e)” Handoff performance of L2 mobility should be enough to support QoS requirement for real time service including packetized video and voice

▣ Suggestions on 3GPP2 All IP Ad Hoc NAM◈ NAM is to be prepared in a way of supporting improved L2 mobility (Possib

ly in regarding of restructuring the duplication of L2/L3 Mobility Management) for real time packet data service