OSI
Open Systems Interconnect Stack
TCP/IP
TCP/IP Stack
Application
Application Layer
Handles interaction between the user and the application. TLS/SSL encryption is also handled at this layer.
Protocols at this level:
- SMTP
- FTP
- DNS
- HTTP
- POP
- HTTP
- SSH
- NTP
What software/hardware operate at this layer?
Web browsers, such as chrome, operate at the application layer.
Transport
Transport Layer
This layer is responsible for end-to-end error free transmission of data.
Protocols at this level:
- SCTP
- TCP
- UDP
What software/hardware operate at this layer?
Gateways (not covered in the CIE A Level)
Internet
Internet Layer
Responsible for delivering packets from host to destination using IP addresses.
Protocols
- IP
- ARP
- RARP
- ICMP
- IGM
What software/hardware operate at this layer?
Routers function at this layer
Network Link
Network Link Layer
This layer utilizes hardware addresses and is responsible for the physical transfer of data from node to node.
What software/hardware operate at this layer?
Hubs, Switches & Bridges operate at this layer
TCP vs UDP
TCP vs UDP
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