Internet Protocol Version 6 (IPv6)
===================================

This section covers the IPv6 protocol, its routing methods, and addressing mechanisms. IPv6 resolves limitations in IPv4, such as address exhaustion, and introduces new features for more efficient networking, including simplified headers, improved multicast, and integrated security support.

.. toctree::
   :maxdepth: 1
   :hidden:
   :includehidden:

   IPv6/ipv6
   IPv6/IP_Routing_Protocols
   IPv6/IPv6_Addressing

.. list-table::
   :widths: 20 60 20
   :header-rows: 1

   * - Category
     - Description
     - Use Case
   * - IPv6 Basics
     - Introduction to IPv6, including its address structure, packet format, and differences from IPv4.  
       *Highlights features like larger address space, simplified header, and auto-configuration.*
     - Future-ready internet and enterprise networking.
   * - IP Routing Protocols
     - Describes routing protocols adapted or designed for IPv6.  
       *Includes OSPFv3, RIPng, EIGRP for IPv6, IS-IS, and MP-BGP.*
     - Efficient and scalable IPv6 routing in modern networks.
   * - IPv6 Addressing
     - Explains IPv6 address types and assignment methods.  
       *Includes unicast, anycast, multicast, link-local, global unicast, and unique local addressing.*
     - Device identification, service discovery, and traffic routing in IPv6 networks.

.. tab-set::

   .. tab-item:: IPv6 Basics

      **RFC:** RFC 8200 (Obsoletes RFC 2460)

      **Main Features:**

      - 128-bit address space (e.g., 2001:0db8::1) allowing trillions of unique addresses
      - Simplified and fixed-size header (40 bytes) compared to IPv4
      - No need for NAT — end-to-end connectivity and global addressing
      - Built-in support for IPsec, mobility, and auto-configuration (SLAAC)
      - Eliminates broadcast; uses multicast and anycast instead
      - Enhanced quality of service (QoS) with Flow Label field

      **Use Cases:**

      - Modern enterprise and ISP networks
      - IoT and mobile systems requiring a large address pool
      - Future-proofing infrastructure for global internet growth

      **Alternative Protocols:**

      - IPv4 – Legacy version still widely deployed
      - MPLS – Protocol-independent forwarding
      - IPX – Deprecated Novell protocol

      .. panels::
         :container: container pb-4
         :column: col-lg-12 p-2
         :card: What You Will Learn in This Section

         **Let us learn more about IPv6 Basics:**

         * :ref:`Learnings in this section <IPv6_step1>`

         * :ref:`Terminology <IPv6_step2>`

         * :ref:`Version Info <IPv6_step3>`

         * :ref:`IPv6 Version&RFC Details <IPv6_step5>`

         * :ref:`IPv6 Basic Setup on Ubuntu using IPv6 <IPv6_step20>`

         * :ref:`IPv6 Basic Setup on Ubuntu using IPv6 <IPv6_step21>`

         * :ref:`IPv6 Protocol Packet Details <IPv6_step6>`

         * :ref:`IPv6 Usecases <IPv6_step7>`

         * :ref:`IPv6 Basic Features <IPv6_step8>`

         * :ref:`IPv6 Feature : 128-bit Addressing <IPv6_step9>` 

         * :ref:`IPv6 Feature : Simplified Header Structure <IPv6_step10>`

         * :ref:`IPv6 Feature : Multicast Support <IPv6_step11>`  

         * :ref:`IPv6 Feature : Stateless Address Autoconfiguration (SLAAC) <IPv6_step12>`  

         * :ref:`IPv6 Feature : Improved Security <IPv6_step13>`

         * :ref:`IPv6 Feature : Flow Label Field <IPv6_step14>`

         * :ref:`IPv6 Feature : Extension Headers <IPv6_step15>`   

         * :ref:`IPv6 Feature : Hop Limit <IPv6_step16>` 

         * :ref:`IPv6 Feature : Classless Addressing <IPv6_step17>` 

         * :ref:`IPv6 Feature : Efficient Routing <IPv6_step18>` 

         * :ref:`Reference links <IPv6_step19>`

         .. button-link:: ./IPv6/ipv6.html
            :color: primary
            :shadow:
            :expand:

            Jump to "IPv6 Basics"
.. tab-set::

   .. tab-item:: IP Routing Protocols

      **RFCs:**

      - OSPFv3: RFC 5340
      - RIPng: RFC 2080
      - EIGRP for IPv6: Cisco implementation
      - IS-IS for IPv6: RFC 5308
      - MP-BGP: RFC 4760

      **Main Features:**

      - IPv6-ready versions of major routing protocols
      - **OSPFv3:**  
        - Supports IPv6 prefixes, per-link operation
      - **RIPng:**  
        - UDP port 521, simple distance-vector protocol
      - **EIGRP for IPv6:**  
        - Cisco proprietary, similar to EIGRPv4
      - **IS-IS:**  
        - Uses TLVs for IPv6 reachability
      - **MP-BGP:**  
        - Supports both IPv4 and IPv6 route advertisement

      **Use Cases:**

      - Dynamic IPv6 routing in enterprise and ISP networks
      - Transition from IPv4 to IPv6 with dual-stack routing
      - Scalable and policy-based route distribution

      **Alternative Protocols:**

      - Static routing – For small or controlled environments
      - IPv4 routing protocols – Used during IPv4/IPv6 coexistence

      .. panels::
         :container: container pb-4
         :column: col-lg-12 p-2
         :card: What You Will Learn in This Section

         **Let us learn more about IPv6 Routing:**

         .. button-link:: ./IPv6/IP_Routing_Protocols.html
            :color: primary
            :shadow:
            :expand:

            Jump to "IPv6 Routing Protocols"
.. tab-set::

   .. tab-item:: IPv6 Addressing

      **RFCs:** RFC 4291, RFC 4193, RFC 4862, RFC 6724

      **Main Features:**

      - 128-bit hexadecimal addresses using CIDR notation
      - **Unicast:** One-to-one communication
      - **Multicast:** One-to-many; replaces broadcasting
      - **Anycast:** One-to-nearest communication
      - **Special addresses:**  
        - ::1 (loopback)  
        - :: (unspecified)  
        - fe80::/10 (link-local)  
        - fc00::/7 (unique local)  
        - 2000::/3 (global unicast)
      - Stateless Address Autoconfiguration (SLAAC)

      **Use Cases:**

      - Host and router identification in IPv6 networks
      - Automatic address assignment and service discovery
      - Secure and efficient traffic routing

      **Alternative Protocols:**

      - IPv4 – Simpler, but less scalable
      - DHCPv6 – Stateful IP assignment
      - NDP – Replaces ARP for neighbor discovery

      .. panels::
         :container: container pb-4
         :column: col-lg-12 p-2
         :card: What You Will Learn in This Section

         **Let us learn more about IPv6 Addressing:**


         .. button-link:: ./IPv6/IPv6_Addressing.html
            :color: primary
            :shadow:
            :expand:

            Jump to "IPv6 Addressing"