Introduction
The most critical system for a battleship is the combat system, which integrates all of the essential information of a combat situation to aid the commander in analyzing information about the battle and making decisions about tactics. All information related to the battle, including astronomical and hydrological data, as well as data from radar, sonar, sensors, and weapons systems, will be sent to the situation room for further analysis.

Generally speaking, combat systems can be divided into two categories, depending on whether the control system is centralized or distributed on the battleship. Centralized control systems are easy to maintain and are less complicated, but they are slow to process data from many sources simultaneously, and can easily cause the ship's communication system to fail once the system is damaged. As far as applying distributed control systems to a combat system is concerned, such systems are more sophisticated, and must maintain a faster computing speed. However, they will not cause the entire ship's operations to be suspended while other parts of the system are damaged. For this reason, distributed control systems are widely used in new generation combat systems.

A complete combat system includes a combat information platform, computing system, and sub-systems, such as radar system, weapons system, sonar system, direction system, and communication system. Information from these systems is integrated in the situation room to form the well-known C4ISR system, which works with an Ethernet network. In the situation room, integrated information is compared and analyzed with the existing combat database to provide more accurate information to the commander.

On battleships, combat systems are required to work under a severe strain in order to defeat the ship's adversaries. Information from various systems needs to be gathered and integrated in real-time to improve reaction speed. In short, a combat system cannot be allowed to fail. For this reason, a reliable redundant communication network is necessary.

Recommended Solution
Since a battleship's combat system is so important, the network used to communicate with all related systems needs to be more robust. The network structure that applies to a combat system is designed with a dual Gigabit redundant Turbo ring to provide redundancy for both the network and switch. On the device level, each controller or PLC is connected to two Ethernet switches from different ring topologies. If one of the networks or switches is damaged, the other network or switch will act normally to back up the damaged element. In addition, a broad bandwidth with fiber Gigabit ring can completely satisfy the long-haul and high transmission demands of a combat system.