There are two types of VLAN connection links and they are Access link and Trunk link.
This type of link is only part of one VLAN, and it’s referred to as the native VLAN of the port. Any device attached to an access link is unaware of a VLAN membership the device just assumes it’s part of a broadcast domain, but it has no understanding of the physical network.
Switches remove any VLAN information from the frame before it’s sent to an access link device.
Trunks can carry multiple VLANs. A trunk link is a 100- or 1000Mbps point-to-point link between two switches,between a switch and router, or between a switch and server. These carry the traffic of multiple VLANS from 1 to 1005 at a time.Trunking allows you to make a single port part of multiple VLANs at the same time.
Trunk links are required to pass VLAN information between switches. A port on a Cisco switch is either an access port or a trunk port. Access ports belong to a single VLAN and do not provide any identifying marks on the frames that are passed between switches.
HOW TO CONFIGURE TRUNK PORTS
SWITCH A: switchA(config)#vlan 10 switchA(config-vlan)#name SALES switchA(config-vlan)#exit
SWITCH B: switchB(config)#vlan 10 switchB(config-vlan)#name SALES switchB(config-vlan)#exit
SWITCH A: switchA(config)#interface fa0/1 switchA(config-if)#switchport access vlan 10
SWITCH B: switchB(config)#interface fa0/2 switchB(config-if)#switchport access vlan 10
TRUNK PORT ENABLING ON SWITCH A
SWITCH A: switchA(config)#interface fa0/14 switchA(config-if)#switchport mode trunk
TRUNK PORT ENABLING ON SWITCH B
SWITCH B: switchB(config)#interface fa0/14 switchB(config-if)#switchport mode trunk