What does OSI Layer 7 (Application) do?

OSI Layer 7 (Application) provides the protocols for process-to-process communication — the interface between user applications and the network (HTTP, FTP, SMTP, DNS, etc.). It is about the protocols, not the apps themselves.

Layer 7 = Application Layer

Provides protocols for process-to-process communication - the interface between user applications and network services.

NOT about applications themselves - about the protocols they use!

Common protocols:

• HTTP/HTTPS (web)
• FTP (file transfer)
• SMTP/POP3/IMAP (email)
• DNS (name resolution)
• DHCP (IP assignment)

Memory tip: Layer 7 is the "App layer" - where applications talk to the network.

Go deeper:

• Application layer — the protocols (HTTP, FTP, SMTP, DNS) and how OSI's L7 differs from TCP/IP's Application layer.