D-Link DES-3326 User Manual page 110

24-port NWay Ethernet Switch User's Guide
The Ethernet header is 14 octets that include the source and
destination MAC address and a type code.
There is no relationship between the MAC address of a network
node and its IP address. There must be a database of Ethernet
addresses and their corresponding IP addresses.
Different protocol families can be in use on the same network.
The type code field allows each protocol family to have its own
entry.
A checksum is calculated and when the packet is received, the
checksum is recalculated. If the two checksums are different,
the packet is dropped.
Figure 5-14. Ethernet Packet Header
When a packet is received, the headers are removed. The
Ethernet Network Interface Card (NIC) removes the Ethernet
94 Switch Management and Operating Concepts