ECOLANG - Communications Language for Ecological Simulations Network

This document describes the communication language used in one multiagent system environment for ecological simulations, based on EcoDynamo simulator application linked with several intelligent agents and visualisation applications, and extends the initial definition of the language. The agents actions and perceptions are translated into messages exchanged with the simulator application and other agents. The concepts and definitions used follow the BNF notation (Backus et al. 1960) and is inspired in the Coach Unilang language (Reis and Lau 2002).

💡 Research Summary

The paper presents ECOLANG, a formal communication language designed for the EcoSimNet framework, which integrates the EcoDynamo ecological simulator with multiple intelligent agents and visualization tools. ECOLANG adopts a Backus‑Naur Form (BNF) syntax, extending it with curly braces for repetition and square brackets for type annotation, thereby enabling concise description of complex message structures. Each message follows the template <MESSAGE> ::= message(<ID> <SENDER> <RECEIVER> <MSG_CONTENT>), where <ID> is a sequential integer generated by the sender, and <SENDER> and <RECEIVER> are string identifiers of the participating applications.

Four principal categories of messages are defined: Connection, Definition, Action, and Perception. Connection messages manage session establishment and termination (connect, disconnect), acknowledgement (accept), and discovery of peer agents (ask_agents, known_agents). Definition messages convey static information about the simulation environment, including region specifications (land or water, with quality and sediment attributes), geometric definitions (points, rectangles, circles, arcs), and model metadata such as dimensions, morphology, and species composition. These messages support creation, deletion, and query operations (define, delete, get_regions, get_region) and provide corresponding result messages that echo the original request identifier.

Action messages enable agents to request operations from the simulator. They are split into domain‑specific actions (e.g., seed, inspect, harvest for shellfish production) and generic simulation control actions. Domain actions carry parameters such as region name, time stamp (either now or Unix epoch seconds), bivalve type, weight specifications, and density. Generic actions cover model lifecycle (open_model, close_model, get_model, save_conf), execution control (initialise, run, stop, pause, step), specification manipulation (get_classes, select_classes, get_variables, set_variable_value, get_parameters, set_parameters, get_time, set_time, subdomain), and result registration (output_file, select_variables, log, trace). Every action is tagged with an <ACTION_ID> that matches the <ID> of the originating request, ensuring a one‑to‑one correlation between request and response.

Perception messages deliver the outcomes of actions and unsolicited simulator events. They include seed_result, inspect_result, harvest_result for domain actions, and a suite of system‑level results (model_result, exec_result, specs_result, reg_result, event_msg). Each perception references the original <ACTION_ID> and reports success or failure (ok/failed) together with any relevant data, such as harvested weight, variable values, or parameter sets.

The protocol emphasizes consistency and traceability through the mandatory use of identifiers, explicit success flags, and detailed payload definitions. It also provides versioning information, header files, library and DLL specifications, and dependency listings, facilitating implementation across diverse programming environments. By formalizing the exchange of actions and perceptions between agents and the EcoDynamo simulator, ECOLANG enables reliable, extensible, and interoperable communication in complex ecological simulation scenarios, thereby supporting researchers and developers in constructing, experimenting with, and visualizing sophisticated ecosystem models.