Transcript Document
Wireless Communication CDMA EVDO Systems Dr. Mustafa Shakir Contents CDMA 1X Packet Data Service Functional Entities 1X Packet Data Service Status CDMA Evolution EV-DO Network Architecture EV-DO Channel structure PDSN As a access gateway , PDSN (packet data service node) provides the cdma2000 mobile station with services for Internet access or Intranet access. PDSN acts as an interface between Radio Network and Packet Data Network. Provides the mobile station with Simple IP access service or Mobile IP access service. In Simple IP,PDSN acts as a Network access server, while in Mobile IP,PDSN acts as Foreign Agent (FA) for Mobile Station. At the cdma2000 1x stage, the maximum access rate available for each subscriber is 153.6kbps, and at the cdma2000 1x EV-DO (Evolution Data Only) stage, the maximum access rate available for each subscriber will be as high as 2Mbps. PDSN acts as a client of AAA server. AAA AAA authenticates the script file information of the subscribers, authorizes data services, and Collects accounting information from PDSN, completes accounting. Authentication simple IP and mobile IP. Authorization subscriber configuration information. Accounting collecting billing data(both radio specific and IP network specific) for each packet data call. Home Agent HA(Home Agent) is responsible to maintain the current registration of the MS and redirections packets to the PDSN(FA). Performs authentication and authorization uses AAA server. Assigns MS home IP addresses after authentication by mobile IP protocol. Only uses in Mobile IP. CDMA2000 1x Packet Domain Access Method Simple IP Access Similar to the network access through dialing-up modem on the fixed telephone . Assigning dynamic IP addresses and accomplishing the data communication with MS as the calling party . Simple protocol, easily accomplish, but data communication will be interrupted when MS handoff between different PPP link. Access Method (Cont.) Mobile IP Access Providing a route mechanism in the internet. Assigning MS fixed addresses to connect to any sub-network. Accomplishing the data communication with MS as the calling party or the called party, and holding data communication when MS handoff between different PPP link. PDSN Mobile IP Access Signaling BTS User Data PDSN/FA BSC/PCF FW MS BTS IP Network FAAA HA FW APP Servers HAAA Contents CDMA 1X Packet Data Service Functional Entities 1X Packet Data Service Status CDMA Evolution EV-DO Network Architecture EV-DO Channel structure Service Status Service Status Active/Connected: There are traffic channels between Mobile Station (MS) and BS, and data can be exchanged between them. In this state, the A10 and PPP connections are kept. Dormant: There are no traffic channels between MS and BS. A10 and PPP connections remain. Null/Inactive: There are neither traffic channels nor A10 connections between MS and BS. Besides, there is no PPP connection between MS and PDSN. How to know? When Active, Dormant & Inactive 1. About “DRS” When a mobile terminal sends an origination request with a packet data service option specified, it will include the Data Ready to Send (DRS) bit. When DRS bit set to 1 to indicate that it has data to send. When DRS bit set to 0 to indicate that it has not data to send, just to update the network How to know? When Active, Dormant by & Inactive 2. About “packet data inactivity timer” In BSC or MS, they both have a packet data inactivity timer to identify whether there are data frame sent/received or not. The timer should be reset whenever non-idle Radio Link Protocol data frames are sent or received. If the packet data inactivity timer expires, the BSC or MS should release the traffic channel. Comparison of Wireless Systems (CDMA Evolution) 1 Gbps 100 Mbps Wi-MAX 10 Mbps WLAN CDMA2000 1xEVDO 1 Mbps UMTS Bluetooth 100 kbps GSM / GPRS Inside Office Inside Building Low Mobility Outside High Mobility Outside Contents CDMA 1X Packet Data Service Functional Entities 1X Packet Data Service Status CDMA Evolution EV-DO Network Architecture EV-DO Channel structure 1X EVDO Network Structure Source AN PCF PDSN IP Network AT A12 Target AN AAA AN AAA IP Network AT AN AT access terminal AN Access Network A12 authentication used by the AN to authenticate 1x EV-DO Access terminal Comparison of EVDO and 1x Networks HLR AAA MSC MS/AN BTSB BSCB ANAAA PCF PDSN Network Implementation