Network Layer (Chapter 4) Evaluation Flashcards

A set of vocabulary flashcards covering the operation, management, and configuration of network layer protocols including NAT, ICMP, RIP, OSPF, and BGP based on the Chapter 4 evaluation.

NAT (Network Address Translation)

A mechanism used by computers on a local network that allows them to be addressable from the Internet by sharing a single public IP address assigned by the ISP, where hosts are differentiated by ports.

NAT Table

A stored relationship table used by a NAT-enabled device to map incoming and outgoing datagrams between NAT IP/Ports and original IP/Ports.

Tunneling

A mechanism to achieve compatibility between IPv4 and IPv6 by inserting IPv6 datagrams into the payload field of IPv4 datagrams so they can be communicated between IPv4 routers.

ICMP (Internet Control Message Protocol)

A network layer protocol used for connectivity analysis and error testing, capable of obtaining information such as RTT and reachable networks.

ping and traceroute

Known analysis tools that employ the ICMP protocol to perform network connectivity tests.

show ip route

A Cisco router command used to visualize the routing table.

Wildcard Mask

Also known as an inverse mask, it is a bitmask indicating which parts of an IP address are relevant for the execution of a specific action.

ifconfig

A command used in the Linux operating system to obtain the private IP address of a computer.

curl ifconfig.me

A command used in the Linux operating system to obtain the public IP address of a computer.

ip route 192.168.20.0 255.255.255.0 10.10.10.2

The Cisco configuration command on router R1 to establish a static route towards PC2's network via the next hop address $10.10.10.2$.

RIP (Routing Information Protocol) Configuration

A routing process enabled in Cisco routers using the router rip command followed by network statements for each directly connected network.

OSPF (Open Shortest Path First) Configuration

A routing protocol configuration using the router ospf [process-id] command, where networks are identified by address, wildcard mask, and assigned to a specific area (e.g., area 0).

BGP (Border Gateway Protocol) Configuration

A configuration used to enable connectivity between different autonomous systems (AS) using the neighbor [IP] remote-as [AS-number] command and redistribute protocol.