Lesson 1: IPv6 Introduction and Addressing
The lesson opens with the IPv4 exhaustion problem. There are only about 4.3 billion IPv4 public addresses, and the planet uses many times that number of devices. NAT delayed the crisis but did not solve it. IPv6 brings a 128 bit address space, which is large enough that every grain of sand on every beach could be addressed. You will then learn the eight group hexadecimal notation, the rules for compressing zeros with the double colon, the rules for unique local addresses, the role of multicast addresses, and the use of solicited node multicast for efficient neighbor discovery. By the end of the lesson, you can convert any long form IPv6 address into its compressed form and back, and you can identify the type of address by looking at its leading bits.
Lesson 2: IPv6 Address Distribution and GUA
IPv6 addresses follow a strict allocation hierarchy. IANA allocates large blocks to the Regional Internet Registries. The RIRs allocate smaller blocks to Local Internet Registries and large enterprises. The LIRs assign prefixes to service providers, and the service providers delegate prefixes to customers. This lesson walks you through the hierarchy, then focuses on the Global Unicast Address range, which is the IPv6 equivalent of public IPv4. You will see how a prefix like 2001 colon db8 colon slash 32 is carved into smaller customer blocks, how an enterprise plans its internal allocation, and how subnetting in IPv6 differs from IPv4. The lesson closes with practical addressing recommendations used by real service providers.
Lesson 3: GUA, Link Local and Host Communication
Every IPv6 enabled interface holds at least two addresses at the same time. One is the Global Unicast Address, used for communication beyond the local link. The other is the Link Local Address, used only for traffic between devices on the same segment. This dual address model exists for a reason. Local protocols, such as routing protocol hellos, must continue to work even when the global prefix changes. This lesson explains why link local addresses are mandatory, how hosts find each other on the local segment without broadcast, and how a packet flows from a host to a remote destination through the routed network. You will trace the journey of a packet from the source interface to the gateway, then onto the wider IPv6 internet, and you will understand the role of each address along the way.
Lesson 4: Neighbor Discovery Protocol (RS, RA, NS, NA)
ARP is removed in IPv6. Its job is replaced by the Neighbor Discovery Protocol, which uses four ICMPv6 message types. Router Solicitation, sent by a host to ask for routing information. Router Advertisement, sent by a router to share its prefix, its lifetime and its options. Neighbor Solicitation, sent to resolve a neighbor link layer address or to verify reachability. Neighbor Advertisement, sent as a response. This lesson walks you through each message with packet captures in the EVE-NG lab. You will see how a fresh host learns its prefix from a Router Advertisement, how SLAAC builds the host part of the address, how Duplicate Address Detection runs before any address is used, and how the four messages knit together to form the IPv6 local layer.
Lesson 5: DAD and IPv6 Header
Duplicate Address Detection ensures that no two devices on the same link can share the same address. Before a host begins to use a new address, it sends a Neighbor Solicitation to its own address. If a reply arrives, the address is duplicate and is not used. This is a small but critical safety mechanism, and the lesson explains it in detail. The second half of the lesson dissects the IPv6 header field by field. You will compare the IPv6 header with the IPv4 header, see the fields that were removed, understand why fragmentation has moved out of the main header, and learn how extension headers are chained when extra processing is required. By the end you can read a raw IPv6 packet and explain every field.
Lesson 6: IPv6 Routing with OSPFv3
OSPF for IPv4 is well known. OSPFv3 is its IPv6 cousin, with some quiet changes inside. This lesson explains why a new version of OSPF was created. The first reason is that OSPF was tied to IPv4 in its packet format. The second reason is the protocol designers used the opportunity to clean up a few legacy issues. You will see how OSPFv3 uses link local addresses for adjacency, how the LSA types were renumbered and rethought, and how IPv6 prefixes are carried inside the LSAs. You will then walk through full OSPFv3 configuration on Cisco routers in EVE-NG, neighbor formation, route exchange and verification with show commands.
Lesson 7: BGP Address Families and Transition Technologies
BGP was designed in the IPv4 era, but the protocol designers had the foresight to make it extensible. The Multiprotocol BGP extension, written as MP-BGP, lets a single BGP session carry many types of routes. IPv6 unicast is one of those address families. This lesson explains the address family concept, configures BGP for IPv6 in the lab, and shows neighbor formation and prefix exchange with show commands. The second half introduces transition technologies, which is the family of techniques that allow IPv4 and IPv6 to coexist. You will see the high level shape of tunneling techniques and translation techniques, and how an enterprise plans the move from a pure IPv4 network toward an IPv6 ready future.
Lesson 8: Dual Stack and NAT64
Dual Stack is the simplest transition strategy. A device runs IPv4 and IPv6 side by side, and traffic flows over the version that the destination supports. This works well as long as both stacks are healthy, but it doubles the operational load. NAT64 solves a different problem. When an IPv6 only client wants to reach a service that is reachable only on IPv4, NAT64 translates between the two protocols, with help from DNS64 for name resolution. This lesson walks through the configuration of NAT64 in the EVE-NG lab, verifies the translation in real time, and closes with guidance on when to deploy Dual Stack and when NAT64 is the right answer. The lesson finishes the course with a clear roadmap for taking the next steps in your IPv6 journey.
