4.1.1 - IPv4 Datagram Header

Flashcards about IPv4 Datagram Header and related protocols

Ethernet

Operates at the Physical and Data Link layers of the OSI model (layers 1 and 2).

Internet Protocol (IP)

Provides logical network addressing and forwarding at the Network layer (layer 3).

32-bit source and destination addresses

What two fields does the IPv4 header contain for addressing?

Internet Control Message Protocol (ICMP/1)

Used for status messaging and connectivity testing.

Internet Group Messaging Protocol (IGMP/2)

Used with multicasting.

Generic Routing Encapsulation (GRE/47)

Used to tunnel packets across an intermediate network, as in some VPN implementations.

Encapsulating Security Payload (ESP/50) and Authentication Header (AH/51)

Used with the encrypted form of IP (IPSec).

Enhanced Interior Gateway Routing Protocol (EIGRP/88) and Open Shortest Path First (OSPF/89)

Protocols used by routers to exchange information about paths to remote networks.

Version field

Indicates the version of Internet Protocol in use.

Length fields

Indicate the size of the header and the total packet size.

Protocol field

Describes what type of data is encapsulated in the payload.

6 for TCP and 17 for UDP

What are the IP protocol type values for TCP and UDP?