Blockade

[thedoctorking]

What is the effect of blockade? How do you achieve a blockade? How do you prevent your enemies from achieving a blockade?

[Stelteck]

Being blockaged give points each turn to your ennemy, and can increase your unrest, leading to possible a revolution and terrible consequences.

To prevent a blockage, you must have enough ships in your home sea relative to your enemy ships.
To blockage someone, you must have enough ships in his home sea.

Each ship have a blockage value that you can see in ship's list. Only the class of the ship matter. (Best ships for blockage are B or BB, heavy ships). The quality of the ship is not taken into account. For blockage numbers matter.
You can sometimes avoid being blockaged by a stronger navy, by spamming cheap coastal battleships. (But do not send them in battle, they will be sinked).

[WLRoo]

A blockade is achieved when you have 110% of the blockade value in your opponents primary Home Sea Zone (where newly constructed ships appear).

Note that some nations get a modifier to their blockade strengths to represent their geographical location being more suited or less suited to establishing a blockade - Russia, stuck at the end of the Baltic Sea has a 0.7 multiplier whereas the UK, positioned with great access to the mouth of the Baltic Sea and good access to the Mediterranean Sea gets a 1.2 multiplier.

[mrchuck]

Each ship have a blockage value that you can see in ship's list. Only the class of the ship matter. (Best ships for blockage are B or BB, heavy ships). The quality of the ship is not taken into account. For blockage numbers matter.
You can sometimes avoid being blockaged by a stronger navy, by spamming cheap coastal battleships. (But do not send them in battle, they will be sinked).

CVs have nearly double the value (14 vs 8), and supercarriers probably more though I haven't seen one so far. Watch out for this.

[EvanJones]

I am not sure what is going on.

Is it:

A simple comparison of (modified) blockade strengths if minimum blockade number is met?

Or is it a comparison of naval strength [sic], where DDs add to it, etc., if minimum blockade number is met?

It makes a big difference, and I'd like to know the answer.