Q1) A router packet receives an IP packet with the TTL field set to 1. Will the router forward this packet?
In the IP datagram or packet as they are mentioned, the TTL is the field in the IPV4 header where it is thought of as an upper bound so that the IP datagram can exist in the Internet system and can be delivered and not discarded. The, TTL is set by the sender of the datagram and is reduced when it travels through every router in the network. If the TTL is set to zero before the datagram reaches the destination, then the datagram is discarded. The purpose of the TTL is to avoid situations where a undeliverable packets keeps circulating on the Internet indefinitely. Yes, here in the above case the router packet receives an IP packet with the TTL field set to 1, since the count is greater than 0, yes, the router will forward the packet.