Topology A Cisco 1841 router has the following interfaces: Two Fast Ethernet interfaces: FastEthernet 0/0 and FastEthernet 0/1 Two serial interfaces: Serial 0/0/0 and Serial0/0/1 l The interfaces on your routers can vary. Packet Tracer Activities are referenced throughout these chapters for additional most user PCs, a router will have multiple network interfaces. l These interfaces can include a variety of connectors.