1490, which is simply a multiprotocol encapsulation method over Frame Relay. RFC 1490 is a
specification for putting type codes into the Frame Relay headers and the ability to forward
different protocols over Frame Relay. It covers both bridged and routed traffic. RFC 1490 was
first supported in Cisco IOS version 10.3(1).
left, which is trying to reach 192.168.200.1. The router strips the data link header Ethernet
encapsulation. It then looks at Layer 3 and recognizes it is an IP packet. The router looks at the
IP header, finds a destination address of 192.168.200.1, and says it is not a directly connected
interface. It looks in the IP routing table for the most explicit match, finds the next hop (in this
case, Router B or 192.168.1.2), and an interface to send the data out on (Serial 0). This has to
go via Frame Relay to Router B.