Learn Turkish: Güvenlik protokolü sadece kapıyı kapatmaktan ibaret değildir. - The security protocol doesn't consist solely of closing the door.

The word ibaret means "consisting of" or "made up of" and it always requires the preceding word or phrase to take the ablative case ending (-DAn). To express "consisting of doing something," you use the infinitive verb (-mAk) plus the ablative suffix, giving us kapatmaktan (from closing).

Why is the ablative suffix written as -tan instead of -dan in kapatmaktan?

This is a brief refresher on consonant assimilation. The infinitive kapatmak ends in the voiceless consonant k. This forces the standard ablative suffix -dan to change its first letter to a voiceless equivalent, becoming -tan.

Why does kapı take the accusative ending -yı here, even though the sentence ends with a form of "to be"?

The accusative suffix belongs to the action of closing (kapatmak), not the main sentence structure. Even when a verb acts as a noun (like an infinitive), it still governs its own objects. Because it refers to a specific door ("closing the door"), kapı takes the definite accusative suffix -yı.

Why is there an -ü at the end of Güvenlik protokolü?