Overview

This Function shall be capable of providing the following facilities:

(1) The ability to take responsibility for maintaining the store of Travel Information Data.
(2) The ability to update the store contents with data that is received from the Produce Travel Information Function and the Travel Information Operator through the Provide Travel Information Operator Interface Function.
(3) The ability to output travel information to Travellers when a request is received through the Provide Traveller Information Interface Function.
(4) The ability to output travel information to the Output Travel Information Function at the request of the Travel Information Operator.
(5) The ability to provide data from the store to the Provide Travel Information Operator Interface Function as a result of a request from the Travel Information Operator.

Functional Requirements

(a) continuously monitor for the receipt of the updated travel information and request travel information data flows
(b) when the first of the data flows in (a) is received, load the new information into the store of Travel Information Data in the load travel information data flow, deleting any information that it replaces
(c) when the second of the data flows in (a) is received, get the required travel information from the store of Travel Information Data using the read travel information data flow and send it to the Provide Travel Information Interface function in the travel information response data flow
(d) when the output travel information data flow is received, get the requested information from the store of Travel Information Data using the read travel information data flow and send it to the Output Travel Information function in the travel information for output data flow
(e) when the request current travel information data flow is received, get all of the current information from the store of Travel Information Data using the read travel information data flow and send it to the Provide Travel Information Operator Interface function in the requested current travel information data flow.

Diagrams

Parent Higher Level Function

• 6.6 Provide Traveller Information

Input logical dataflows

• ptja_output_travel_information
• ptja_read_travel_information
• ptja_request_current_travel_information
• ptja_request_travel_information
• ptja_updated_travel_information
• ptja_update_other_travel_data

Output logical dataflows

• ptja_load_travel_information
• ptja_requested_current_travel_information
• ptja_travel_information_for_output
• ptja_travel_information_response

User needs