📘 OSPFv2 vs OSPFv3 and IPv6 Overview for PCNSE Exam

1. OSPFv2 vs OSPFv3

Feature	OSPFv2	OSPFv3
IP Version Support	IPv4	IPv6
Addressing	Uses IPv4 addresses	Uses IPv6 addresses; utilizes link-local addresses for neighbor discovery
Authentication	Built-in OSPF authentication	Relies on IPv6's IPsec for authentication
LSA Types	Types 1-5, 7	Includes new LSA types: Link-LSA (Type 8) and Intra-Area-Prefix-LSA (Type 9)
Configuration	Configured using network statements	Configured directly on interfaces
Multiple Instances	Not supported	Supports multiple instances per link

Address Length: 128 bits, represented in hexadecimal.
Address Types: Unicast, Multicast, and Anycast.
Address Notation: Uses colon-separated hexadecimal; leading zeros can be omitted, and consecutive sections of zeros can be compressed using "::".
Link-Local Addresses: Required for network operations; automatically assigned to interfaces.
Routing: OSPFv3 is used for dynamic routing in IPv6 networks.
Transition Mechanisms: Dual-stack, tunneling, and translation methods are used to facilitate IPv4 and IPv6 coexistence.

Understand the differences between OSPFv2 and OSPFv3, especially in terms of configuration and operation.
Be familiar with IPv6 addressing, notation, and the significance of link-local addresses.
Know how to configure and verify OSPFv3 on Palo Alto Networks firewalls.
Be aware of how IPv6 impacts security policies and routing configurations.