Once upon a time, there were two kingdoms at war. One of them had more starships and access to magnetic monopoles. For the purpose of this question, they could have been another exotic particle. Little railguns on drones can shoot these particles ar a speed of 3 km/s. The starships have no means to detect the monopoles. Monopoles of opposite magnetic charge attract each other and produce a lot of energy when coming in contact. (This is theoretical and not experimentally proven. Another possibility is that new monopoles might be created after the collision. I am ignoring that.) So the railguns fire a monopole with one sign, followed by another of opposite sign with a small delay but higher speed, so that it can catch up for a devastating explosion in the target. A single shot has 50% chance to destroy or disable a starship. Each drone can deliver a single shot before it has to return to the mothership. The starships can create, as they travel, wormholes restricted to a million kilometres length. These are primarily used to escape when attacked. All ships block wormholes in a range of a lightsecond, so they can't be used for attack.
Below are some numbers I obtained from Google based on existing systems and some guesswork:
- Radar can detect drones at 5 km distance
- Drone camera can see as far as half km
- Plasma engines of the starships sped is 20 km/s
- Reaction time for crew 2s,
- Four drones per standard ship, but could be less if they have seen battle
- Drones have no radar but can talk to starships and starfighters
- radar has 3000 km range to detect a starship
- Starfighters have a top speed of 26,000 km/h. They are not that good at attacking starships.
The standard weapons are high energy beams ten times less effective than monopoles, but they can kill drones with a single shot
Fleets/combat groups are made up of around twelve ships depending on how much battle they have seen. Non standard ships are less common by a factor of five. Some of them are far more expensive than standard ships.
So the types of ships:
- Standard ships, four drones, no starfighters, can generate one hologram that fools drones half of the time.
- Drone carrier ships, 40 drones, no starfighters
- Starfighter carriers, carry up to sixty starfighters, max two per fleet
- Shield ships generate plasma shields. On average twenty shots are needed to destroy such a ship. She can be used to protect other ships. You can't have more than two shielders in a given fleet due to cost.
- Radar ships, the only ships that can detect drones, no more than two per fleet
- Hologram ships, generate up to ten holograms of starships and use other tech to fool drones. No more than two per fleet.
- Hospital, minesweepers, minelayers, one of each per fleet.
- Cargo civilian ships. Have no means to defend themselves but can escape through wormholes. Around twenty in a convoy.
How do you defend a convoy, being the weaker side without access to monopoles?
My first attempt is as follows: Mines are placed around each wormhole jump point. There is one of each specialist ships in a fleet. A shielder protects the starfighters carrier. The hologram generator places holograms at the edge of the fleet. All the standard ships cluster around the radar ship.
FOOTNOTES There has been a lot of fuss in the comments. Of course, not every number is correct or valid for some definition of it. We don't even know if monopoles exist. The main idea is that we have mosquitoes, birds, and aircraft. That is in terms of detection, speed, size. We can bend the rules by introducing magical stealth. I am not doing that. Besides someone already answered so I can't edit the figures to not invalidate the answer. So there we are.