Lets consider you are brand new to this game. You know nothing about it. You're looking here because your GM or someone in power needs you to learn basic defense. I'm going to assume you just started, in a brand new server and that there are lots of active players around.
There are three types of players in the AE universe.
1.) Offensive (Zerg)
2.) Defensive (Sim)
3.) Farms (Farms)
The first will in the early stages of the game, try to rush out fleet in order to OCC bases for pillages/trades for players who don't know what they're doing leaving their bases vulnerable. They will have ok defenses but will not invest heavily as they have fleet to liberate their bases.
The second will sim away - totally focus on economy and defending their bases. They believe that if you do not attack anyone and have a lot of defense that people will leave you alone.
The third will provide you with a lot of money.
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Some people don't like putting up turrets or even a simple photon turret for a defense. People like this are the ones that are usually targeted (Farms), because people who do this generally either have little fleet that can get blown away, or even have a large fleet though it's so badly composed that too gets blown away. Some defenses are better then others, though I will review each.
You have to understand that the best defense is low econ/high defenses. But this will not bring you in any money, and it will hinder you. There are effective ways to do this, but you have to be a very active and knowledgable player. In order to first understand base defense, you need to have some goals.
[*] Planetary Rings By Level 30
[*] Photon Turrets By Level 20
[*] Ion Turrets by Level 15
[*] A single fighter on every base, and Laser Turrets by Level 10
Now to know if you're base is profitable, here is a pillage chart. This is what other players get if they successfully attack your base.
BarracksBase Econ Pillage Bonus
10 54
20 216
30 486
40 864
50 1350
60 1944
70 2646
80 3456
90 4374
100 5400
110 6534
120 7776
130 9126
140 10584
150 12150
160 13824
170 15606
180 17496
190 19494
200 21600
They are equivalent to having five corvettes. (Totally useless)
Generally for --
Laser Turrets
When you're coming out of level protection at level 10, you will probably only have these unlocked. You should build a set of these on each of your planets until you get missiles for better defense. You will probably have trade routes too, so you should build a fighter so that your TR's cannot be plundered.
Generally for lv 10
Missile Turrets
Your finally getting too some ok defenses, though these are still generally bad for you to get if you are beyond level 15. These are good against small and medium units, which can stop most corve and destro attacks that you would experience during this level which makes these a valuable but not that effective turret.
Generally for lv 10-15
Plasma Turrets
These are better defenses for the newly founded player, once you reach these you should tear down any other defense structure and build up some of these. However - they do not last you that long until you make double Ions. Sometimes skipping this defense can save time and money.
Generally for lv 15-20
Ion Turrets
These will make any attacker think twice about attacking your base, as they are starting to become powerful deterrents for shaking off base attacks. Past level 20 however, these are sort of dull. As you enter level 20, you have to be aware of the fact that anyone to up to level 29.99 can attack you. The difference in economy/fleet/technology is VERY different at the early stages, especially for this level jump. You will want to make sure you get to the next turret as quickly as possible.
Generally for lv 15-20
Photon Turrets
The best turrets for the new player, pair these up with some ion turrets and you should be all set for awhile. Make sure to stay on-top of making some ships paired with your turrets by now, because you should be in a phase were you can start building fleet by now. These defenses will generally hold up, and is the first turret to defend you from a single battleship.
Generally for lv 20-25
Disruptor Turret
Getting the tech and such for this you will have a nice defense for future battles. These are nice for the generally average player because of the fact that it can fend off against fighter drops and the fact that it can defeat a dread by itself.
Generally for lv 25-30
Deflection Shields
These are ok defenses if you pair it up with disrupter turrets. These can stop smaller ships in their tracks if their the only defense you have on your base. They can also stop big shields like battleships, though they can't stop a nicely teched dread and on their own they definetly cannot stop a titan. I do not recommend building shields, they are a big waste of energy, and an investment you could be providing for planetary rings. The only thing shields do is increase the size of the fleet required to take the base.
Generally for lv 25-30
Planetary Shield
One of the best defenses, by themselves they can stop fighter drops, they can also stop a single dread, perhaps 2 or 3 if you have good tech. (That would also include Fighters in hangers) If your pshield is nicely teched it should also be able to stop a titan if you have fleet and CC's on your planet(s). You should remember however, if this is the only thing on your base that it can get shield-raped. This can be done by attack/repair by these bigger ships, so it is unwise to leave a lone shield on a planet.
Generally for all lv's past 30
Planetary Ring
The best defense for your planets, once you get the nessacary tech for these you should build these on your planet. These can stop titans dead in their tracks, and if you have duel rings built on your planet you can stop a levi with relative ease. once you get 3 or more more on your planet, you should be able to stop most fleets coming to your planet.
Your Main Goal for all Planets.
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++Great Combinations For Defense (Turrets)++
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Photon + Ion Combo *Lv 15-20*
This stops most of the small ships that are at your level that most people build. Once you get to level 25 you should be able to tech up some different Turrets for your planet.
Disrupter + Deflection Combo *Lv 25-30*
A nice combination in order to stopa titan if tuned the right way. in order to do this properly you should build two of each on your planet. This is also a combo to stop fighter drops because of the brute force behind the disrupter turrets.
Pshield + Pring Combo *lv 30+*
Stops almost everything in its tracks if you double up on both structures. A fleet on your planet combined with these will scare most agressors as most people don't want to break rings but older players do not have a problem with tackling such bases.
Note: In war - no one cares about profit and it is easy to make any base profitable with enough fleet. Remember that just because you have a lot of turrets doesn't mean that someone can't make it profitable. There are a lot of people that still do not know how to set up a proper defense and can easily get pillaged or kick farmed from a guild because they are way to easy of a target.
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These defenses are some of the best defenses, but that doesn't mean your all set yet. You still need basic fleet on your planet in order to stop attacks. Even if you have 5 Prings on your planet, if you don't have any fleet you are at a major disadvantage. Your trade routes are now available for people to pirate unless you have at least 1 fighter or ship at your base.
For fleet, there is truely only one defense ship: Fighters
Fighters are the most efficient ship in the AE world. Though, it goes exactly vice cersa. If you have 10k fighters but no turrets/shields, then your base can get dread/titan smashed. So all in all, you have to have a nice balance of fleet and turrets/shields to be efficent.
Your Ideal Goal:
2000 Fighters
1 Dread
3 Prings
Command Centers Note: Command centers do not help on the defensive, they only apply on attacking. These are generally only useful for a Stronghold base or a base that is occupied.
