I am new to switch and i was going through the article about the switches and in the article it says to allow traffic to pass through a particular port, then that port needs to be in the trunk mode. We bought a new 3750 Cisco Switch and the Switch is directly connected to 5 2950 switches and one Cisco Pix firewall and One internal router. An Engineer came and confiugred the same. All internet related traffic hits the switch and gets forwarded to the pix firewall which is working fine. The Enginner had made the ports that are connecting to 2950 switches as trunk port(vlan 10) and access-port for the port that is connecting to cisco pix and internal router with vlan as 30 and 60 respectively. How all vlan traffic can pass through to the Cisco Pix firewall which is connected to a port in the switch which is in access mode and vlan 30? Is there any link that points to some Lab Configuration of switches so that i could get a better understanding of the switch configuration.
Thanks in Advance