Data Management, Transaction Models and Enabling Technology for Mobile Commerce. In this discussion… Introduction Enabling Technology Data Management Transaction Models Query Processing Recovery. Introduction. E-commerce applications run on fixed, reliable networks.
Data Management, Transaction Models and Enabling Technology for Mobile Commerce
The WAP Architecture for Mobile Commerceprovides a scalable and extensible environment for application development for mobile devices in wireless environment. Each layer of the architecture is accessible by the layers above, as well as by other applications and services
Fig 1: WAP Architecture
Wireless Application Environment (WAE): for Mobile Commerce
Provides interface to build and run applications of wireless environment
Wireless Session Protocol (WSP):
Offers both connectionless and connection oriented services and Responsible for long-lived session state, sessions suspend and resume with session migration, reliable and unreliable data push.
Wireless Transaction Protocol (WTP):
Provides unreliable and reliable one-way and two-way requests and transactions, asynchronous transactions and data unit concatenation.
Wireless Transport Layer Security (WTLS): for Mobile Commerce
Provides data integrity, privacy, authentication and protection to the upper layers.
Wireless Datagram Protocol (WDP):
Operates above the bearer services supported by the different networks and offers a consistent service to the upper layer protocols.
e.g. short message, circuit-switched data, and packet data.
GPRS (General Packet Radio Service) for Mobile Commerce
Fig 2: GPRS Architecture for Mobile Commerce
Table 1: GPRS Interfaces for Mobile Commerce
3. Data Management for Mobile Commerce
Global data management : for Mobile Commerce network level issues such as location, addressing, replication, broadcasting etc.
Local data management: energy efficient data access management and query processing at the user level
Fig 3: Mobile database architecture for Mobile Commerce
Data access management for Mobile Commerce
Broadcast data organization is known as for Mobile Commercebroadcast program or broadcast schedule.
Fig 4: Broadcast programs for Mobile Commerce
Broadcast Disks: for Mobile Commerce (Acharya et al) uses cyclic, non-flat dissemination architecture.
Data Indexing: for Mobile CommerceExtra meta-data is added to data objects so that clients only need to selectively tune to broadcast channel to extract the desired data.
Data Replication and Consistency Management: for Mobile Commerce
- reduces access time
- transparency of mobility
- selection of data and service stations
- updation of database
- consistency management
4. Transaction Models for Mobile Commerce
Kangaroo Transaction Model for Mobile Commerce(Dunham et al)
Fig 5: Kangaroo Transaction Model for Mobile Commerce
Isolation-Only Transactions for Mobile Commerce(Satyanarayan et al)
Two-tier Model for Mobile Commerce(Gary et al)
Team Transaction model for Mobile Commerce(Gore and Ghosh)
Fig 6: Team Transaction Model for Mobile Commerce
Multi-database Transactions for Mobile Commerce(Yeo and Zaslavsky)
Fig 7: Architecture of MDSTPM for Mobile Commerce
Toggle Transactions for Mobile Commerce(Dirckze and Gruenwald)
PRO-MOTION for Mobile Commerce(Crysanthis)
Fig 8: PRO-MOTION System Architecture for Mobile Commerce
Table 2: Comparison of Transaction Models for Mobile Commerce
5. Query Processing for Mobile Commerce
Query By Icons for Mobile Commerce(Antonio Massari)
Fig 9: QBI Architecture for Mobile Commerce
Query Processing using Summary Databases for Mobile Commerce(Madria et al)
Query Processing using Summary Databases for Mobile Commerce(contd..)
Fig 10: Mobile Database Environment with Summary Databases for Mobile Commerce
6. Recovery for Mobile Commerce
Recovery Protocols for Mobile Commerce( M. M.Gore and R. K. Ghosh)
1.Timeout protocol: executed by MSS. MSS maintains a timer to measure the inactivity period of mobile host and initiates rollback for the transaction on timeout.
2.Disconnect protocol: executed by mobile host due to resource problems (like battery discharge, weak signal etc.).
3. Hand-off protocol: executed by mobile host, when it switches from one MSS to another MSS. Mobile host sends it’s new MSS address to the old MSS and conveys old MSS information to the new MSS while switching from cell to cell.
4. Migration protocol: In this protocol migration information and new settings of mobile host are communicated to the old MSS by the new MSS, before timeout or disconnect protocol execution at old MSS
Fig 11: Mobile Transaction Recovery Protocols for Mobile Commerce
Recovery Guarantees for Mobile Commerce(Martin and Krithi Ramamritham)