2 IP Networking
WHAT IS IP?
IP (Internet Protocol) is an agreed standard that defines how devices communicate over the Internet or
other Internet-like Ethernet network.
IP is part of a 7-layer architecture consisting of
• Physical Layer (Layer 1)
• DataLink Layer (Layer 2)
• Network Layer (Layer 3)
• Transport Layer (Layer 4)
• Session Layer (Layer 5)
• Presentation Layer (Layer 6)
• Applications Layer (Layer 7)
PHYSICAL LAYER (LAYER 1)
This refers to the electrical impulses (or light signal or radio signals) carried on the cable (or fiber, air or
other physical medium). For IP, the physical layer is usually Ethernet.
DATALINK LAYER (LAYER 2)
This is where data packets are translated to and from bits, which can be transferred on the Physical Layer
NETWORK LAYER (LAYER 3)
Layer 3 provides switching and routing to create paths for data to be transmitted from node to node
within the network. This is the layer that gives IP its name.
TRANSPORT LAYER (LAYER 4)
This layer is responsible for end-to-end error recovery and flow control, enabling transparent transfer of
data between hosts.
SESSION LAYER (LAYER 5)
The Session layer manages exchanges (conversations) between the “applications” on each host.
PRESENTATION LAYER (LAYER 6)
This layer translates between application and network formats, so that communication independent of
data representation such as ASCII, GIF, JPEG etc.
APPLICATIONS LAYER (LAYER 7)
Everything at layer 7 is application-specific, such as Telnet, FTP, WWW browsers, HTTP etc.
To Next Page
Loading...
Need help?
General
