Hi Router is a layer 3 device in OSI model.So when WAN encapsulation is done, Router is used. When a PC dial in to ineternet, frame that is passed to ISP, whether it is a WAN encapsulated frame or ethernet frmae. Please give the details.

hi VTP advertisements are sent over factory default VLAN (VLAN1) using multicast frames. Why multicast frames why not broadcast frames.

hi Switch has different ports. I want to know that either each port in a switch has MAC address or switch has only one MAC address. When STP makes calculations which MAC address will it use?

Dear Sir, In switch ,every ports has different MAC address or one combine MAC address of switch.Is this true? When we talk about switch'MAC address in STP calculations. Which MAC address STP take either one of the port's MAC address in switch...