Network+/Standards/OSI Model/OSI Components

This table shows the OSI model layers and the components that operate at each layer.

OSI Layer Purpose TCP/IP Layer Protocol Packet Data Unit Address Device Troubleshoot
Application Interface (API) Application HTTP, SMTP, etc. Message - - Wireshark
Presentation Formatting, Encryption, Compression Application HTTP, SMTP, etc. Message - - Wireshark
Session Authentication, Authorization Application HTTP, SMTP, etc. Message - Gateway NSLOOKUP, NBTSTAT, Wireshark
Transport Reliability Transport TCP, UDP Segment (TCP), Datagram (UDP) Port Firewall TELNET, NETSTAT, Wireshark
Network Addressing, Routing Internet IP, ICMP Packet IP Address Router IPCONFIG, PING, TRACERT, Wireshark
Data Link Logical Link Control, Media Access Control Link Ethernet, Wi-Fi, PPP, etc. Frame MAC Address Switch, Bridge, Access Point Lights on device, ARP, Wireshark
Physical Transmission Link CAT 5, RJ-45, etc. Bit - Hub, NIC, Cable Lights on device

One easy way to remember OSI layer is to think:[source?]

A - All

P - People

S - Seem

T - To

N - Need

D - Data

P - Processing