The Use case starts whenever a train enters a station in a section, which is equipped with data loggers. The relays integrated with tracks/signals and points at the station transmit the raw data to the data logger, which in turn is networked to a central server at the divisional control. Whenever detection of a train on the track occurs or a signal device is operated, the data logger logs the event and transmits the data to the divisional control. The interface software will map the individual events received from the data logger and map to COA application specific events
This raw data (in hexadecimal or any other format) contains information like RelayId, LineId, Data Logger Id, Sequence Numbers, Record Id , Timestamp and Status/Value. This information would be mapped to relevant details required by COA application like arrival time/departure time/run through time, line no and station id.
Train Linking
The sequence of steps to link a train entering into a section equipped with data loggers is as follows
• Train enters into the station equipped with data loggers
• Raw data is generated by data logger equipment and gathered by the interface
software
• COA application extracts the relevant raw data, refines the same and stores them in
data logger interface tables after mapping
• A pre scheduled process extracts this information from the data logger interface
tables and trigger the appearance of a dot on the chart at the station representing the beginning of the section.
• User then links the train to the dot on the chart by entering the train id.
In the event of the non-working of data logger equipment, the system shall have the provision of turning off this option and switch to the manual mode of train ordering through the Train Ordering screen. The system shall also generate suitable alerts informing the user about the event of non functioning of data logger equipment and also intimate the resumption of functioning of the same.
6.0 Assumptions
• Datalogger equipment is assumed to installed on a complete board in continuous
fashion.
3 Operational Concepts and Scenarios
Distributed Architecture:
The system would be implemented initially on two pilot divisions of Southern Rly and ultimately across the IR territory covering approximately 80 control offices. The entire geographical area is divided into various sub-areas for operational and administrative control. Each divisional control office is more or less independent of other divisions and requires interaction with adjoining divisions only for incoming trains and a major portion of the data generated is thus consumed within the division. Therefore a division should be able to work independently even if adjoining divisions’ systems are down through a
distributed architecture. A divisional level illustration of COA implementation is depicted below
COA Application will have an integrated approach where there will be multiple divisional implementations each of which will have individual physical storage. Certain amount of data will be passed across using the messaging via CAS. Each division will comprise of a 2 servers interconnected with each other with clustered database. And each division will have a storage in which the physical data will be stored.
The system is based on the three-tier architecture comprising of the Presentation, Business and Data Layers.
Business Layer: This layer captures the business rules as classes/components that can be reused across application. As a whole this layer houses the full logic of the application developed in C#
Data Layer: This layer the repository of information/data of the whole application in a centralized place, which can be accessed from the business rules. This layer implements the concept of both physical and logical independence of data and would be in Oracle 10g.
Physical Architecture:
The Client Desktop will have windows xp to access the application server. The application server, which will have Windows 2003 server, serves the data and passes on to the database and inturn it passes to the Storage where the physical data would be stored. Some part of the data would be passed from the storage to the CAS via Messaging.
Highly Available System:
24x7 availability to users with minimum down time is an important requirement of Control Office Application. The system is highly critical and thus would be having a very high redundancy to ensure non-stop operation. The system would give priorities to certain important requests and be scalable enough to increase the number of clients without degrading performance. Although, the interface with other divisions allied systems is asynchronous, the system would be near real time so that the response is compromised only to a limited extent.
The exchange of information within the division as well as with other divisions and allied systems would be highly reliable. The divisional servers shall be in cluster with fail over features
Evolutionary MIS:
The Control Office Application would have a robust database to cater to any changes in the database design in preliminary stages of its development. Any decision to introduce new data structures or modifications to existing data structures would be easily addressed. There is, therefore, a requirement for evolutionary MIS and scalability of the Control Office Application. The divisional Control Room Operations software shall be developed on a
Security of the System
The system will have various security levels namely Application Level Security, Database Security and Physical Security.
The security of COA shall be the responsibility of shall be at two levels.
Central Level
The Central Security Administrator(CSA) shall be responsible for creating and modifying the users for the central level referential and timetabling data
Divisional Level
The Divisional Security Administrator shall be responsible for the security of COA and other divisional level interfaces
Physical Security
The Divisional/Central Security Administrator shall be responsible for the physical security of the system
Their responsibilities shall include
o Maintenance of security of Database Servers by keeping it locked and
prohibiting entry of any unauthorized person to prevent thefts and other untoward incidents
o Access to the database server shall be protected by password and
only the System Administrator shall be aware of the same.
o Maintenance of multiple power supply connections for uninterrupted
power supply
Database Security
The following measures shall be taken for ensuring database security
• Role based access
Only the Divisional Security Administrator shall have access to the database directly. All the other users shall access the database through the application.
• Encryption of Stored Data
Certain important and sensitive data shall be stored in encrypted format to prevent unauthorized access.
• User Maintenance
The DSA shall create userids of of various roles such and each of the roles shall have tasks associated with it. Access shall thus be controlled by role based security. E.ach role shall have a list of tasks associated with it. New roles can be created by the DSA which may have additional tasks associated with it. Tasks are in turn are mapped to various functionalities provided by the COA frontend application.
4 Interface Requirements
The COA Application would have a user friendly GUI interface with rapid data entry capability and actions through a minimum of keystrokes /clicks. The User Interface and design is liable to changes, at least initially, on account of addition or modification in functionality as the system has to be implemented at various locations with varied kind of operations