Chap. 1 The basics- Sound, Electrical, Signal, Electromagnetic Spectrum

Transcription

1 WCDMA and CDMA2000 Protocol CDMA 이동통신실무 2006, 08, 04 Jae-Hyun Kim Homepage: Wireless Information and a Network Engineering Research Lab. School of Electrical and Computer Engineering Ajou University

2 목 차 3GPP/3GPP2 소개 3GPP W-CDMA 프로토콜 3GPP W-CDMA 프로토콜세부기능 3GPP W-CDMA W MAC 3GPP W-CDMA W RLC 3GPP W-CDMA W RRC 3GPP2 CDMA2000 프로토콜 3GPP2 CDMA2000 프로토콜세부기능 3GPP2 CDMA2000 MAC 3GPP2 CDMA2000 LAC MAC 프로토콜연구이슈 (QoS) CDMA 시스템및네트워크구조 2

3 3GPP2 CDMA2000 프로토콜구조 -. 일반 -. 서비스엔티티및인터페이스구조 -. 채널구조

4 일반 동기식 IMT-2000 방식의표준화 3GPP2(3rd Generation Partnership Project 2) 에서규격을정의 미국의 TIA (Telecommunication Industry Association) 한국의 TTA (Telecommunications Technology Association) 일본의 ARIB (Association of Radio Industries and Business) 중국의 CWTS (China Wireless Telecommunication Standard) CDMA2000 을공동으로규격정의 동기식 CDMA2000 시스템의무선네트워크 IS-2000 표준프로토콜스택 계층 1 - PHY (Physical Layer) Air interface( 변복조, 코딩등 ), 상위계층 PDU 처리 계층 2 (Data Link Layer) MAC (Medium Access Control), LAC (Link Access Control) 멀티미디어지원, 높은효율성, 서비스품질관리 계층 3 (Application Layer) 단말기나기지국의동작에대한실제적인프로토콜을담당 메시지의처리, 통화절차나핸드오프과정등에대한행동을규정 호처리, 데이터프로토콜의상위계층, 음성신호처리 4

5 일반 계층 2 MAC 계층 Multiplexing, RLP(radio link protocol), QoS등의기능수행 LAC 계층 재전송기능, 어드레싱, 인증, 메시지구분수행 LAC 계층에서는시그널링에만적용되고일반트래픽에는적용되지않음 계층 3 시그널에서오는신호들은공통채널 (Common Channel) 로매핑 계층 3 시그널링은 SRBP와 LAC을통과하여상위계층 3 시그널링엔티티로이동 LAC 기능은데이터의정확한전달을위한오류제어음성이나데이터들은트래픽채널 (Traffic Channel) 로매핑 음성서비스는 Multiplexing과 QoS Delivery를통과, 물리계층에서 FCH로전달데이터서비스 오류제어를위한 RLP (Radio Link Protocol) 과 QoS Delivery를통해전달 5

6 일반 그림 5-1. CDMA2000 에정의된 protocol stack 6

7 서비스엔티티및인터페이스구조 CDMA2000 무선구간프로토콜스택 사용자평면 (User Plane) 과제어평면 (Control Plane) 구분 3 계층 2계층 IS-95 의계층 2는단순히 acknowledgment 처리 CDMA2000 에서는계층 2가 MAC 과 LAC 으로구분 MAC 과 LAC 의기능이강화된이유 처리하는서비스의다양한종류 QoS 관리가다름 CDMA2000 에서는계층관리평면 (layer management plane) 을따로정의 일종의자원관리관점에서처리하기위한평면 계층간통신의의미를명확히하기위하여프리미티브를정의 상위계층에서하위계층으로전송하는경우하위계층에서상위계층으로전송하는경우하위계층에서특정상태를보고하는경우 7

8 서비스엔티티및인터페이스구조 대문자는물리채널의미 소문자는논리채널의미 트래픽은 dedicated channel 로전송 시그널링은 dedicated channel 또는 common channel로처리데이터들은어떤경우에상위계층시그널링을거쳐서전송되는경우가있는데이것은 Data Burst Message라는특별한메시지를통해서전송되는경우 (SMS 메시지서비스 ) 그림 5-2. 단말기의 service entity 및 service interface 구조 8

9 채널구조 그림 5-3. CDMA 2000 에서지원하는순방향채널종류 9

10 채널구조 CDMA2000 에서지원하는순방향채널종류 파일럿신호 (PICH: Pilot Channel) 송신다이버시티 (Diversity) 를위한 OTD (Orthogonal Transmit Diversity) STD (Space Time Diversity) 방식제공 동기채널 (SYNCH: SYNC Channel) 방송채널 (BCCH: Broadcast Control Channel) 호출채널 (PCH: Paging Channel) 긴급호출채널 (QPCH: Quick Paging Channel) 통화채널 FCH (Fundamental Channel) 패킷멀티미디어통신 SCH (Supplemental channel) 통신도중에전송할데이터트래픽이증가하는경우에추가적인 SCH 할당사용 10

11 채널구조 그림 5-4. CDMA 2000 에서지원하는역방향채널종류 11

12 채널구조 CDMA2000 에서지원하는역방향채널종류 액세스채널 (ACH: Access Channel) 엑세스요구 개선된형태의액세스채널 REACH (Reverse Enhanced Access Channel) 기지국에서통화요구 FCH (Fundamental Channel), SCH (Supplement Channel) 형태의 통화제공 12

13 3GPP2 CDMA2000 MAC -. 일반 -.. Multiplex 부계층 -. 접속채널절차

14 일반 3GPP2 C.S0003-A-2 규칙따름 MAC 계층내부의엔티티들과 MAC 계층과다른계층내의서비스인터페이스, 프리미티브들의교환포함 MAC 계층엔티티들의동작에대한표준절차설명 MAC 계층은 IS-95 에는정의되지않았으나 CDMA2000 에서정의된계층 CDMA2000 은고속데이터를근간으로한멀티미디어서비스에중점 CDMA2000 에서정의하는 MAC 무선데이터를위한 RLP 패킷데이터또는음성서비스를위한시그널링을처리하는 SRBP QoS, multiplexing 기능수행상위계층 MAC 계층의 RLP 엔티티 Multiplex 부계층 물리계층으로전송 RLP 는새로운데이터또는재전송데이터를처리하는엔티티간 peer to peer 로이루어짐 14

15 Multiplex 부계층 Multiplex 무선구간으로전송을돕기위하여상위계층에서생성된트래픽 ( 음성신호및데이터 ) 및제어신호를하나의프레임으로만드는역할 송신 Multiplex 부계층 다양한소스들 ( 상위계층시그널링, 데이터서비스및음성 서비스 ) 로부터정보결합 전송하기위하여물리계층 SDU(Service Data Unit) 들을생성 수신 Multiplex 부계층 물리계층에포함된정보들을분리 해당엔티티 ( 상위계층시그널링, 데이터서비스및음성 서비스 ) 에정보전달 15

16 Multiplex 부계층 QoS delivery Multiplexing 과동일한계층에위치함 동일한 QoS 끼리모아서처리하는역할 멀티미디어서비스를제공할경우에필수적인서비스별 QoS 관리 화상전화에서음성및영상신호는실시간처리는보장되어야 하지만어느정도오류는발생해도무방함 파일전송일경우실시간처리는보장되지않아도되지만오류가 발생하면안됨 16

17 Multiplex 부계층 RLP (Radio Link Protocol) 다양한종류의서비스를처리하기위해서는반드시 RLP 를사용 오류가발생한 RLP 프레임에대하여재전송하는방안정의 제어신호는반드시 SRLP (Signaling Radio Burst Protocol) 와 LAC 계층을사용 Multiplex 부계층의동작 상위계층에서발생한데이터를 Multiplex 부계층에서는별도의 LPM (Logical to Physical Mapping) table 을가지고무선구간으로 전송 고속데이터전송전용채널 (SCH: Supplemental Channel) 과시그널링전송이가능한 FCH(Fundamental Channel) 를구분처리 17

18 Multiplex 부계층 그림 6-1. Multiplex 부계층의동작 18

19 Multiplex 부계층 MuxPDU (Multiplex sublayer Protocol Data Unit) 상위계층에서수신한 SDU 와 Multiplex 부계층에부가한헤더정보 ( 포맷비트들 ) 로구성 프로토콜동작에서 MuxPDU 가다시하위계층에서는 SDU 가됨 고속데이터전송채널인 SCH 에대해서는별도로 LTU (Logical Transmission Unit) 단위로처리 FCH (Fundamental Channel) MuxPDU type 1 또는 MuxPDU type 2 를처리, 시그널링이전송 SCH (Supplemental Channel) MuxPDU type 3 이상이처리 Multiplex 부계층에서필요한정보를부가하여형성된 PDU 가 MuxPDU 가되며이 MuxPDU 가물리계층에서의 SDU 가됨 19

20 Multiplex 부계층 CDMA2000 의 Multiplex 부계층의가장큰특징중의하나가패킷데이터처리에중점 데이터전용채널인 SCH 를 Multiplex 부계층에서는 LTU 단위로 CRC 를붙임 물리계층의부담을줄이기위한일종의 Hybrid ARQ 방식 MAC 계층에서물리계층으로전송시고속데이터채널인 SCH 에대해서는전체적인재전송을줄이기위하여 LTU 단위로재전송 Multiplex Option 의표현방법 20

21 Multiplex 부계층 Multiplex Option Rate set, Maximum date block, Date block size, MuxPDU type, Format Descriptor (16 비트 ) Max_Data_Block - Multiplex 부계층에서적용되는실제데이터의크기를 비트단위로정의 Data_Block_Size - Rate set 1( 또는 Rate set 2) 을기본크기로하여 2 배 크기를 double size 라함 멀티미디어서비스의경우에는 variable Data_Block_Size 형태가사용 MuxPDU type - 물리계층에서어떻게데이터가섞여져있는지를정의 MuxPDU type 1 : IS-95 의 rate set 1 의형태로무선구간으로전송 MuxPDU type 2 : 14.4Kbps 계열의 rate set 2 의형태로무선구간으로전송 21

22 접속채널절차 (Access Channel Procedures) 접속절차 단말기에서기지국에접속하기위한것 응답메시지를전송, 시스템에등록수행, 시스템에등록수행, 전화를 걸기위한발신, 데이터호접속등에적용 랜덤접속 (Random Access) 다른단말기와접속과정에서충돌이발생 충돌발생시단말기는임의의시간뒤에재접속을시도하는방식 고정된시간뒤보다는임의의시간을지연시키는것이확률적으로 충돌이적게발생 22

23 접속채널절차 (Access Channel Procedures) 그림 6-2. 접속절차 -#1 23

24 접속채널절차 (Access Channel Procedures) 시스템접속을위한최소의단위는 Access Probe 프리앰블 (preamble) 기지국에서다음정보인메시지를쉽게인지할수있도록안내역할 실제데이터 Access Probe 가모여서하나의 Access Sequence 를이룸 Access Sequence 사이는랜덤지연 (random delay) 랜덤지연은충돌발생고려 Access Sequence 들이모여서 Access Sub-Attempt 을이룸 Access Sub-Attempt 들이모여서다시 Access Attempt 가됨 모든절차는 F-PCH 또는 F-BCCH 로전송되는 System Overhead Information 인 Access Parameter Message 에정의 24

25 접속채널절차 (Access Channel Procedures) 그림 6-3. 접속절차 -#2 25

26 접속채널절차 (Access Channel Procedures) Access Probe 사이에도랜덤지연을사용 다른단말기의접속시도와충돌을방지하기위한것 하나의 Access Probe 를기지국에전송한후응답을받지못할경우다시 송신전력을증가시켜재전송 이의최대송신전력역시 System Overhead Information 에정의 단말기에서송신전력을높임 높은에너지잡음 (Interference) 작용 제어 필요 CDMA2000 에는대부분접속채널에 Reverse Pilot Channel 이포함 IS-95 보다시스템접속률이훨씬높음 단말기가시스템에접속을시도하는순간부터전력제어 (Power Control) 이적용 기본적으로시스템의도움없이단말기가자체적으로수행하는 Open Loop Power Control 이적용 26

27 참고문헌 1 of Revision A of TIA/EIA/IS 진한도서, IMT-2000 이동통신원리, 김현욱외 3 인 27

28 용어정리 ACH Base station (BS) Blank data block CCCH Configured Multiplex Option Csch Data Block DCCH Dedicated Dsch Dtch DTX EACAM Access Channel A fixed station used for communicating with mobile stations. Depending upon the context, the term basestation may refer to a cell, a sector within a cell, an MSC, or other part of the wireless system A data block that contains no service information bits Common Control Channel The multiplex option number stored in the Service Configuration Record for a physical channel Common Signalling Channel. A point to multipoint logical channel that carries Upper Layer Signalling traffic over a common physical channel Upper Layer Signalling traffic over a common physical channel The unit of information exchanged between the multiplex sublayer and a service or Upper Layer Signalling Dedicated Control Channel An attribute of the forward or reverse physical or logical channel, implying that the channel can only be used by a single user Dedicated Signalling Channel. A point-to-point logical channel that carries Upper Layer Signalling traffic over a dedicated physical channel Dedicated Traffic Channel. A point-to-point logical channel that carries data or voice traffic over a dedicated physical channel Discontinuous Transmission Early Acknowledgement Channel Assignment Message. 28

29 용어정리 EACH Event Enhanced Access Channel A stimulus generated outside of an entity that triggers some procedure within the entity F-BCCH F-CACH F-CCCH FCH Forward Broadcast Control Channel Forward Common Assignment Channel. Forward Common Control Channel Fundamental Channel F-CPCCH F-CPCSCH f-csch f-dsch f-dtch Fill MuxPDU Forward Common Power Control Channel. The physical channel that carries Common Channel power control information on the forward link. Forward Common Power Control Sub-channel. The physical sub-channel that carries Common Channel power control information on the forward link Forward Common Signalling Channel. A csch that carries information from the base station to the mobile station Forward Dedicated Signalling Channel. A dsch that carries information from the base station to the mobile station Forward Dedicated Traffic Channel. A dtch that carries information from the base station to the mobile station A MuxPDU that is not associated with any service, used as filler when assembling a Physical Layer SCH SDU 29

30 용어정리 F-PCH Frame duration IMSI LAC Logical Channel LPM LTU MAC Mobile station Mode A Mode B MS Multiplex Format Indicator Forward Paging Channel. The physical channel that carries Common Channel information on the forward link and that is backward compatible with the TIA/EIA-95-B Paging Channel The duration of a physical channel transmission interval; may be 5, 10, or 20 ms International Mobile Subscriber Identity Link Access Control. Entity that provides assured mode or unassured mode delivery of information across the air interface between the mobile station and the base station Logical connection between peer entities Logical-to-Physical Mapping. Information that is used by the multiplex sublayer for performing the logical-to-physical channel mapping Logical Transmission Unit. One or more Type 3 or Type 5 MuxPDUs with a 16-bit CRC Medium Access Control. Entity that controls the access to and from Upper Layer Signalling, Data Services, and Voice Services to Physical Layer resources A station that communicates with the base station Multiplex sublayer operational mode in which the Radio Configuration is less than or equal to Multiplex sublayer operational mode in which the Radio Configuration is greater than 2 Mobile station. A number that specifies the format of a MuxPDU. 30

31 용어정리 Multiplex Option MuxPDU Null MuxPDU Null Traffic MuxPDU PCCAM PDU Physical Channel Physical Layer SDU Primary Traffic Primitive QOF Used to specify the multiplex sublayer operation for a physical channel. Each Multiplex Option specifies the available data rates for the physical channel (FCH, DCCH or max SCH rate) Multiplex sublayer Protocol Data Unit. One or more data blocks combined according to multiplex option rules A MuxPDU that contains no bits A MuxPDU containing only the lowest negotiated transmit rate primary traffic data block with all bits set to 1 Power Control Channel Assignment Message Protocol Data Unit. An atomic set of data, header information, and control information that is provided by a service user to a service provider Radio transmission link An SDU that is generated by the Mux and QoS Entity that is accepted by the Physical Layer for transmission. Data bits from a service that has the traffic type in the Service Configuration Record set to Primary An abstract, atomic, implementation-independent representation of an interaction between a service user and its service provider Quasi-Orthogonal Function. Set of numerical sequences that are used in place of Walsh codes, and which have pair-wise low cross correlations, but which are less than perfectly orthogonal. 31

32 용어정리 QoS Quality of Service. Metrics that affect the quality of a data service that is delivered to an end user (e.g., throughput, guaranteed bit rate, delay, etc.) Rate Set 1 The set of data rates 9.6, 4.8, 2.7/2.4, 1.5/1.2 kbps, and all integral multiples of 9.6 kbps. Data rates of 2.7 and 1.5kbps are only applicable to reverse Radio Configurations 3 and 5 and forward Radio Configurations 3, 4, 6, and 7 Rate Set 2 R-CCCH R-CCCH slot The set of data rates 14.4, 7.2, 3.6, 1.8 kbps, and all integral multiples of 14.4 kbps. Reverse Common Control Channel Reverse Common Control Channel Slot The reverse Common Control Channel Slot with length RCCCH_SLOTs r-csch Reverse Common Signalling Channel. A csch that carries information from the mobile station to the base station r-dsch r-dtc RLP Reverse Dedicated Signalling Channel. A dsch that carries information from the mobile station to the base station Reverse Dedicated Traffic Channel. A dtch that carries information from the mobile station to the base station. Radio Link Protocol. Connection-oriented, negative-acknowledgment-based data delivery protocol 32

33 용어정리 SCCH Supplemental Code Channel The Physical Layer Supplemental Code Channel SCH Supplemental Channel. The Physical Layer Supplemental Channel SDU Secondary Traffic Service Data Unit. A set of data, header information, and control information that is accepted by a service provider from a service user Data bits from a service that has the traffic type in the Service Configuration Record set to Secondary. Signalling data block The unit of data exchanged between the multiplex sublayer and signalling Signalling Traffic Another name for the signalling information bits sr_id SRBP Service Reference identifier. A unique number assigned to each connected service option instance Signalling Radio Burst Protocol. An entity that provides connectionless protocol for Signalling messages 33

34 3GPP2 CDMA2000 LAC -. 일반 -.. Message Control 과 Status Block -.. LAC 계층내의세부부계층기능 -.. LAC 계층의처리절차예

35 일반 LAC (Link Access Control) 계층 3GPP2 C.S0004-A 규칙을따름 CDMA2000 의시그널링은기본적으로제어시그널링과실제 데이터가별도로처리되는방법을사용 제어평면 전체자원을관리 다양한서비스를처리하기위해제어, 감시, 결정 데이터평면 실제데이터가전송 실제동작을수행하기위해 PDU 를생성 상위또는하위계층으로전송 35

36 일반 LAC (Link Access Control) 계층 계층 3의 SDU (Service Data Unit) 을수신하여처리 MAC 계층에서들어온데이터를가공하여계층 3로전송 상위계층 3 PDU 를 LAC 계층에필요한기능을추가 하위계층으로전송될수록처음의데이터에많은기능을추가되어데이터크기가늘어남 하위계층인 MAC 계층에서처리하기쉽게해줌 몇개의부계층을정의하여이들을모두합하여 LAC 계층이라함 LAC 계층의기능 인증 (Authentication) 처리 재전송 (ARQ ; Automatic Repeat Request) 어드레싱기능 Utility (Protocol Discriminator, Pilot Strength Report) SAR (Segmentation and Reassembling) 36

37 일반 그림 7-1. LAC Data Unit 처리절차 37

38 일반 그림 7-2. CDMA2000 시스널링일반구조 38

39 Message Control 과 Status Block MCSB (Message control and Status Block) 각계층 3 메시지에대한다음과같은정보포함 MSG_TAG PDU의 length 메시지와관련되는 Unique instance identifier Assured mode 또는 unassured mode 전송의확인이필요한지여부 메시지의주소에대한 identity 계층 3로전달되는메시지가중복인지아닌지를알려줌 인증과정이필요한지의여부 적절한 SDU의구분 ( 예 ; 등록, 발신등 ) Logical 채널이 Encryption상태 Message의처음또는마지막비트를받았을때의 CDMA system time 우선순위와같은전송과정에서의지시사항 LAC계층으로부터비정상조건을알림 39

40 Message Control 과 Status Block 계층 3 와 LAC 계층간의정의된프리미티브 L2-Data.Request 계층 3에서계층 2로전달되는 Request로 PDU와 MCSB(Message Control Status Block) 를포함 L2-Data.Confirm 전송한 PDU를수신쪽에서제대로수신했음에대한 Acknowledgement를받았음을알려주는계층 2에서계층 3로전달되는 confirm 프리미티브로 MCSB가파라미터로포함 L2-Data.Indication 계층 2에서받은 PDU를 MCSB와함께계층3로전달하는 Indication 프리미티브 L2-Condition.Notification 계층 2에서확인한비정상이벤트등을계층 3으로보고하는 Indication 프리미티브 L2-Supervision.Request 계층 3서계층2로전달되는 Request로제어명령을포함하는프리미티브 40

41 LAC 계층내의세부부계층기능 LAC 계층 인증부계층, ARQ 부계층, 어드레싱부계층, utility 부계층, SAR 부계층으로구성 각부계층은단말기가 idle state 와 traffic state 에따라다르게적용 그림 7-3. LAC 계층내의세부부계층의종류 41

42 LAC 계층내의세부부계층기능 ARQ 부계층 계층 3의 PDU 를 LAC 부계층으로보낼때 mode 결정 assured mode : 수신단으로부터 acknowledgement 필요 unassured mode : 수신단으로부터 acknowledgement 필요하지않음 Authentication 부계층 r-csch 에서만사용 단말기가 PDU 를보낼때망에서보낸 RAND 값을이용한인증결과인 AUTHR 과 RANDC (Random Challenge value) 및통화횟수를나타내는 call history 파라미터를포함 만일인증을요구하지않을경우에는인증파라미터를포함하지않음 기지국에서는 r-csch 로수신된메시지에서인증파라미터를뽑아내고기지국에서인증 절차를수행할수있을경우에는인증절차를거쳐해당 PDU 의상위계층으로전달 기지국에서인증절차를수행할수없는경우에는인증파라미터를망구성요소로전달 42

43 LAC 계층내의세부부계층기능 어드레싱부계층 Common logical 채널에서만사용 메시지의수신또는송신단말기의 address 를포함 단말기가 address 형식으로는 IMSI, ESN 또는 TMSI 등이사용 Utility 부계층 모든 logical 채널에서포함 Logical 채널의종류에따라서추가하는필드의내용이다름 F-CSCH 와 R-CSCH 의 dedicated logical channel 로 PDU 를전송할 때 Utility 부계층은 message type field 만을포함 43

44 LAC 계층내의세부부계층기능 Utility 부계층 F-CSCH 로기지국이단말로 PDU 를전송할때 Utility 부계층은다음 필드를포함 Message type Field LAC Protocol ID Field Include mask field General page message common fieldextended-encryption field PDU padding field 44

45 LAC 계층내의세부부계층기능 Utility 부계층 R-CSCH 로단말이 PDU 를전송할경우에 Utility 부계층은다음 필드추가 Message type Field LAC Length Field LAC Protocol Field Include Mask Field Extended-Encryption Field LAC Padding Field Radio Environment Report Field PDU Padding Field 45

46 LAC 계층내의세부부계층기능 그림 7-4. 순방향채널에서 LAC 계층의동작 46

47 LAC 계층내의세부부계층기능 순방향채널 User traffic logical channel 과 Signaling logical channel 로구분 User traffic logical channel 은 CDMA2000 에정의된트래픽으로음성신호가대표적인예 Signaling logical channel 은 LAC 계층을관할하는제어블록에의하여제어 Sync channel( 물리계층에존재 ) 은모든단말기에방송되는정보이므로별도의어드레싱처리를하지않으며 ARQ 도필요없음 단방향채널인 BCCH(Broadcast Control Channel) LAC 계층에서처리 반면 Common control channel, Paging channel 등은 common logical channel 로전송, 별도의어드레싱과 ARQ 를사용 대부분의제어신호는이경우에해당됨 LAC 계층에서처리되는채널은모두 logical channel 로서물리계층으로의매핑은 MAC 계층에서이루어짐 순방향채널에서 LAC 계층의한예로그림 7-4 같이순방향트래픽채널을보면, 트래픽상태에서는 ARQ, Utility 부계층만존재 47

48 LAC 계층내의세부부계층기능 그림 7-5. 역방향채널에서 LAC 계층의동작 48

49 LAC 계층내의세부부계층기능 역방향채널 User traffic logical channel 과 Signaling logical channel 로구분 역방향에서 Common logical channel 은 Access channel 이나 Enhanced access channel 을사용하는채널을말함 대부분의경우시스템등록, 음성호발신등과같은시스템 접속단계에서는어드레싱이필요 49

50 LAC 계층의처리절차예 먼저기지국측면에서트래픽데이터를계층 3 SDU 라고하고 ARQ 부계층에서 overhead 가붙고하위계층으로내려오면서계속해서 utility 부계층에서각각 LAC 계층의 overhead 가붙으면서 f-dsch 를통하여 MAC 계층으로전송된다. 기지국측면에서는각각반대의기능을수행하면서원래의트래픽데이터를단말로전송하게된다. 그림 7-6. 트래픽상태에서순방향채널의처리과정 50

51 LAC 계층의처리절차예 그림 7-7. 발신메시지처리절차 단말기에서상대방에게전화를걸거나무선데이터발신을위하여사용되는발신메시지 (origination message) 의처리과정먼저단말측면에서기본적으로발신메시지자체를계층 3 SDU라고하고인증부계층에서 overhead가붙어서계층3 SDU가 capsule화됨하위계층으로내려오면서계속해서arq 부계층, address 부계층, utility 부계층에서각각 LAC 계층의 overhead가붙으면서마지막단계에서 CRC가추가되어 r-csch를통하여 MAC계층으로전송기지국측면에서는각각반대의기능을수행하면서원래의메시지인발신메시지를 Base Station로전송하게됨 51

52 참고문헌 3GPP2 C.s0002-A, physical Layer Standard for CDMA2000 Spread Spectrum Systems, June, GPP2 C.S0003-A, Medium Access Control(MAC) Standard for CDMA2000 Spread Spectrum System, June GPP2 C.S0005-A Upper Layer (Layer 3) Signaling Standard for CDMA2000 Spread Spectrum System, June 2000 TIA/EIA.IS-735, Enhancements to TIA/EIA-41-D & TIA /EIA-664 for Advances Features in Wideband Spread Spectrum Systems, January Common Cryptographic Algorithms, Revision C, An EAR-controlled document subject to restricted distribution. Contract the Telecommunications Industry Association, Arlington, VA, USA. Interface Specification for Common Cryptographic Algorithms, Revision C, Contact the Telecommunications Industry Association, Arlington, VA, USA. ITU-T Recommendation E.212, Identification Plan For Land Mobile Stations, TIA/EIA-95-B, Mobile Station-Base Station Compatibility Standard for Dual- Mode spread Spectrum Systems, February TIA/EIA/TSB58-B, Parameter Value Assignments for CDMA2000 Spread Spectrum System, November,

53 용어정리 Access Attempt Access Probe Access Probe Sequence Access Sub-attempt Automatic Repeat Request (ARQ) Assured Mode The entire process of sending one message and receiving (or failing to receive) an acknowledgment for that message, consisting of one or more access sub-attempts. See also Access Probe, Access Probe Sequence, and Access Sub-attempt One Access Channel transmission consisting of a preamble and a message. The transmission is an integer number of frames in length and transmits one Access Channel message. See also Access Probe Sequence, Access Sub-attempt, and Access Attempt A sequence of one or more access probes on the Access Channel. Other than the reported pilot information, the same Access Channel message content is transmitted in every access probe of an access sub-attempt. See also Access Probe, Access Sub-attempt, and Access Attempt A sequence of one or more access probe sequences on the Access Channel transmitted to one pilot, containing the same message content other than the reported pilot information. See also Access Probe, Access Probe Sequence, and Access Attempt Technique for providing reliable delivery of signals between communicating stations which involves autonomous retransmission of the signals and transmission of acknowledgments until implicit or explicit confirmation of delivery is received Mode of delivery that guarantees that a PDU will be delivered to the peer. A PDU sent in assured mode is retransmitted by the LAC Sublayer, up to a maximum number of retransmissions, until the LAC entity at the sender receives an acknowledgement for the PDU. See also Confirmation of Delivery 53

54 용어정리 Authentication Authentication Response (AUTHR) Base Station Broadcast channel Call History Parameter (COUNT) Code Division Multiple Access (CDMA) Confirmation of Delivery Electronic Serial Number (ESN) A procedure used by a base station to validate a mobile station s identity An 18-bit output of the authentication algorithm. It is used, for example, to validate mobile station registrations, originations and terminations A fixed station used for communicating with mobile stations. Depending upon the context, the term base station may refer to a cell, a sector within a cell, an MSC, or other part of the cellular system. See also MSC When the channel name is written with lower case letters, it refers to the logical channel on which system overhead information is transmitted by the base station. The logical broadcast channel can be mapped to the physical Paging Channel or to the physical Broadcast Channel A modulo-1 64 event counter maintained by the mobile station and Authentication Center that is used for clone detection A technique for spread-spectrum multiple-access digital communications that creates channels through the use of unique code sequences A notification sent by the LAC Sublayer to Layer 3 at the sender, when the LAC entity at the sender receives the acknowledgment for a specific PDU sent in assured mode A 32-bit number assigned by the mobile station manufacturer, uniquely identifying the mobile station equipment 54

55 용어정리 Emergency Call Encapsulated PDU Encapsulated PDU Fragment ESN F-csch F-dsch Full TMSI International Mobile Station Identity (IMSI) IMSI_M IMSI_O IMSI_S A call placed by a mobile station user to request emergency assistance, typically to an emergency services or public safety provider. The method used by a mobile station to identify a call as an emergency call is outside the scope of this document A LAC PDU together with the associated length and CRC SAR parameters A portion of the encapsulated PDU which is limited in size to the available capacity of Lower Layer frames, and is transferred at the interface between the LAC SAR Sublayer and the MAC Sublayer See Electronic Serial Number Forward common signalling logical channel Forward dedicated signalling logical channel The combination of TMSI_ZONE and TMSI_CODE. The full TMSI is a globally unique address for the mobile station A method of identifying stations in the land mobile service as specified in [10]. MIN-based IMSI using the lower 10 digits to store the MIN Operational value of IMSI (either IMSI_M or IMSI_T) used by the mobile station for operation with the base station A 10-digit number derived from the IMSI that is encoded as a 34-bit value. IMSI_S generally corresponds to the last 10 digits of the IMSI 55

56 용어정리 IMSI_S1 IMSI_T A 24-bit value that corresponds to the last 7 digits of IMSI_S True IMSI not associated with MIN. Could be 15 digits or fewer Interface Control Information Data passed between adjacent layers in the protocol stack, together with the SDU, to assist a layer to properly encapsulate/decapsulate the SDU. An example of interface control information in this document is the MCSB LAC PDU LAC protocol data unit transferred between peer Utility Sublayers on the mobile station and the base station LAC Sublayer See Link Access Control Sublayer Layering A method of organization for communication protocols in which the transmitted or received information is transferred conceptually in pipeline fashion within each station, in well-defined encapsulated data units between coordinated processing entities ( layers ). A layer is defined in terms of its communication protocol to the peer layer in the other station and the services it offers to the next higher layer in its own station 56

57 용어정리 Layer 1 (L1) Layer 2 (L2) Layer 3 (L3 Link Access Control (LAC) Sublayer Logical Channel Lower Layers Layer 1 (Physical Layer) provides for the transmission and reception of radio signals between the base station and the mobile station Layer 2 provides for delivery of signalling messages generated by Layer 3 (see below). Layer 2 consists of two sublayers: the LAC Sublayer and the MAC Sublayer (see below). Layer 2 makes use of the services provided by Layer 1. Layer 3 originates and terminates signalling messages according to the semantics and timing of the communication protocol between the base station and the mobile station. Layer 3 makes use of the services provided by Layer 2 The LAC Sublayer is the upper sublayer of Layer 2. It implements a data link protocol that provides for the correct transport and delivery of signalling messages generated by Layer 3. The LAC Sublayer makes use of the services provided by the Lower Layers (Layer 1 and the MAC Sublayer) A communication path between stations, described in terms of the intended use of, and access to, the transferred data, and direction of transfer. A logical channel can be mapped to and from one or more physical channels. In this document, channel names beginning with lowercase letters specify logical channels In this document, layers below the LAC Sublayer (e.g., Layer 1 and the MAC Sublayer) 57

58 용어정리 Mapping Medium Access Control (MAC) Sublayer Message Message Control and Status Block (MCSB) Mini PDU Mobile Country Code (MCC) Mobile Network Code (MNC) Mobile Identification Number (MIN) Mobile Station In this context, the technique for forming associations between logical and physical channels The MAC Sublayer is the lower sublayer of Layer 2. It implements the medium access protocol and is responsible for transport of LAC protocol data units using the services provided by Layer 1. Signalling data unit transferred between the base station and the mobile station. In this document, it should be interpreted as the Layer 3 PDU or the LAC SDU In this 1 document, a parameter block representing the interface control information transferred between Layer 3 and the LAC Sublayer. The MCSB is also used to carry relevant information within the LAC Sublayer A PDU that carries a Layer 3 mini message. The total length of a mini PDU is 48 bits. A mini PDU may not be fragmented, and is carried in a 5 ms physical frame. See also Regular PDU A part of the E.212 IMSI identifying the home country. A part of the E.212 IMSI identifying the home network within the home country The 34-bit number that is a digital representation of the 10-digit number assigned to a mobile station A station in the Public Cellular Radio Telecommunications Service intended to be used while in motion or during halts at unspecified points. Mobile stations include portable units (e.g., hand-held personal units) and units installed in vehicles 58

59 용어정리 Mobile Station Identification Number (MSIN) MSC Multiplex Layer National Mobile Station Identity (NMSI) Number Assignment Module (NAM) PACA PACA Call Physical Channel A part of the E.212 IMSI identifying the mobile station within its home network Mobile Switching Center Protocol Layer situated between Layer 2 and Layer 1 on dedicated channels that is responsible for multiplexing Layer 2 SDUs from multiple sources (user traffic, such as voice or data packets, and signalling traffic) onto the same physical channel, according to priority and QoS criteria A part of the E.212 IMSI identifying the mobile station within its home country. The NMSI consists of the MNC and the MSIN A set of MIN/IMSI-related parameters stored in the mobile station Priority Access and Channel Assignment A priority mobile station originated call for which no traffic channel or voice channel was immediately available, and which has been queued for a priority r-csch assignment A communication path between stations, described in terms of the radio characteristics such as coding, power control policies, etc. In this document, channel names beginning with uppercase letters specify physical channels 59

60 용어정리 Primitive Protocol Data Unit (PDU) Protocol Stack QoS Random Challenge (RANDC) r-csch r-dsch Regular PDU An atomic, well-defined conceptual method of transferring data and control information between two adjacent layers and sublayers. It is conventionally represented as a function invocation, with the data and control information passed as parameters Encapsulated data communicated between peer layers on the mobile station and the base station Conceptual model of the layered architecture for communication protocols (see Layering) in which layers within a station are represented in the order of their numeric designation and requiring that transferred data be processed sequentially by each layer, in the order of their representation. Graphically, the stack is drawn vertically, with the layer having the lowest numeric designation at the base Quality of Service A 32-bit value held in the mobile station. It is used, in conjunction with SSD_A and other parameters, to validate mobile station originations, terminations and registrations Reverse common signalling logical channel (analogous to Access Channel in [11]) Reverse dedicated signalling logical channel (analogous to Reverse Traffic or Fundamental Channel in [11]) A PDU that carries a Layer 3 message other than a mini message. The length of a regular PDU is variable. A regular PDU may be fragmented, and fragments of a regular PDU are carried in 20 ms physical frames. See also Mini PDU 60

61 용어정리 SAR Service Access Point (SAP) Service Data Unit (SDU) Sublayer System Identification (SID Temporary Mobile Station Identity (TMSI) TMSI Zone Unassured Mode Upper Layers Segmentation and Reassembly Conceptual point at the interface between two adjacent layers where services are provided to the upper layer and data and protocol information is exchanged between layers Data transferred between adjacent layers in the protocol stack. Unless specified otherwise, in this document SDU refers to the Layer 3 service data unit transferred to or from the LAC Sublayer A protocol layer of finer granularity within another protocol layer or sublayer. The LAC Sublayer itself may be seen as having several sublayers A number uniquely identifying a cellular or PCS system A temporary mobile station identification assigned by the base station The administrative zone that allows the TMSI to be reused. The TMSI_CODE has to be unique within a TMSI zone but may be reused in a different TMSI zone. The TMSI zone is identified by the field TMSI_ZONE Mode of delivery that does not guarantee that a PDU will be delivered to the peer. The LAC entity at the receiver does not acknowledge a PDU sent in unassured mode General reference to Layer 3 and the layers above it 61