ITN Chapter 6 Quiz Online

The network layer is primarily concerned with passing data from a source to a destination on another network. IP addresses supply unique identifiers for the source and destination. The network layer provides connectionless, best-effort delivery. Devices rely on higher layers to supply services to processes.

The data link layer indicates to the network layer the MTU for the medium that is being used. The network layer uses that information to determine how large the packet can be when it is forwarded. When packets are received on one medium and forwarded on a medium with a smaller MTU, the network layer device can fragment the packet to accommodate the smaller size.

If there are two or more possible routes to the same destination, the metric is used to decide which route appears in the routing table.

A hop is an intermediary Layer 3 device that a packet has to traverse to reach its destination. In this case, the number of hops a packet has to traverse from PC-1 to PC-4 is three, as there are three routers from source to destination.

The command to use for this activity is show ip interface brief in each router. The active and operational interfaces are represented by the value “up” in the “Status” and “Protocol” columns. The interfaces in R1 with these characteristics are G0/0 and S0/0/0. In R2 they are G0/1 and S0/0/0.

A default gateway address allows a switch to forward packets that originate on the switch to remote networks. A default gateway address on a switch does not provide Layer 3 routing for PCs that are connected on that switch. A switch can still be accessible from Telnet as long as the source of the Telnet connection is on the local network.

NAT or Network Address Translation is the process of modifying the IP packet header information on packets going outside the corporate network. Corporate networks typically use private addresses on the inside LAN and need a public address to be able to communicate through the WAN.

A host can ping the loopback interface by sending a packet to a special IPv4 address within the network 127.0.0.0/8.

When a router receives a packet, the router will decrement the Time-to-Live (TTL) field by one. When the field reaches zero, the receiving router will discard the packet and will send an ICMP Time Exceeded message to the sender.

The IOS image is typically stored in flash memory. If the image is not in flash memory when the router boots, the router bootstrap program can look for it on a TFTP server.

The Flow Label in IPv6 header is a 20-bit field that provides a special service for real-time applications. This field can be used to inform routers and switches to maintain the same path for the packet flow so that packets will not be reordered.

The setup mode can be interrupted at any time using the Ctrl-C key combination.