Basic Terminology

 

Abbreviation	Meaning
L2	Link layer (e.g., Ethernet)
L3	Network layer (e.g., IP)
L4	Transport layer (e.g., UDP/TCP/ICMP)
BH	Bottom half
IRQ	Interrupt
RX	Reception
TX	Transmission

 

 

 

 

 

 

An individual package of transmitted data is commonly called a frame on the link layer, L2; a packet on the network layer; a segment on the transport layer; and a message on the application layer.