OSPF - Open Shortest Path First ================================ .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is OSPF?** OSPF (Open Shortest Path First) is a link-state routing protocol used to find the best path for packets as they pass through a set of connected networks. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does OSPF work?** OSPF routers exchange link-state advertisements (LSAs) to build a complete map of the network topology. Each router then uses Dijkstra's algorithm to compute the shortest path to each destination. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What are the different OSPF areas?** * Backbone Area (Area 0): The core of an OSPF network. * Regular Area: Connects to Area 0 and can contain routers and networks. * Stub Area: Limits external route advertisements. * Totally Stubby Area: Further restricts routing information. * NSSA (Not-So-Stubby Area): Allows limited external routes. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What are OSPF router types?** * Internal Router: All interfaces in the same area. * Backbone Router: At least one interface in Area 0. * Area Border Router (ABR): Connects two or more areas. * Autonomous System Boundary Router (ASBR): Connects OSPF to other routing protocols. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow Topics in this section, * :ref:`Learnings in this section ` * :ref:`Terminology ` * :ref:`Version Info ` * :ref:`OSPF Version&RFC Details ` * :ref:`OSPF Basic Setup on Ubuntu using OSPF ` * :ref:`OSPF Basic Setup on Ubuntu using OSPF ` * :ref:`OSPF Protocol Packet Details ` * :ref:`OSPF Usecases ` * :ref:`OSPF Basic Features ` * :ref:`OSPF Feature : Link-State Protocol ` * :ref:`OSPF Feature : Hierarchical Design ` * :ref:`OSPF Feature : Fast Convergence ` * :ref:`OSPF Feature : Cost-Based Metric ` * :ref:`OSPF Feature : Supports VLSM and CIDR ` * :ref:`OSPF Feature : Multicast Updates ` * :ref:`OSPF Feature : Authentication Support ` * :ref:`OSPF Feature : DR BDR Election ` * :ref:`OSPF Feature : Equal-Cost Multipath (ECMP) ` * :ref:`OSPF Feature : Scalable and Extensible ` * :ref:`Reference links ` .. _OSPF_step1: .. tab-set:: .. tab-item:: Learnings in this section * In this section, you are going to learn .. _OSPF_step2: .. tab-set:: .. tab-item:: Terminology * Terminology .. _OSPF_step3: .. tab-set:: .. tab-item:: Version Info * Version Info .. _OSPF_step5: .. tab-set:: .. tab-item:: OSPF Version&RFC Details .. csv-table:: :file: ./OSPF/OSPF_Version_RFC_details.csv :widths: 10,10,10,30 :header-rows: 1 .. _OSPF_step20: .. tab-set:: .. tab-item:: OSPF Basic Setup on Ubuntu using IPv4 * Setup .. _OSPF_step21: .. tab-set:: .. tab-item:: OSPF Basic Setup on Ubuntu using IPv6 * Setup .. _OSPF_step6: .. tab-set:: .. tab-item:: OSPF Protocol Packet Details **OSPF Hello Packet** .. csv-table:: :file: ./OSPF/OSPF_Packetdetails1.csv :widths: 10,20,30,10 :header-rows: 1 **OSPF Database Description (DBD) Packet** .. csv-table:: :file: ./OSPF/OSPF_Packetdetails2.csv :widths: 10,20,30,10 :header-rows: 1 **OSPF Link-State Request (LSR) Packet** .. csv-table:: :file: ./OSPF/OSPF_Packetdetails3.csv :widths: 10,20,30,10 :header-rows: 1 **OSPF Link-State Update (LSU) Packet** .. csv-table:: :file: ./OSPF/OSPF_Packetdetails4.csv :widths: 10,20,30,10 :header-rows: 1 **OSPF Link-State Acknowledgment (LSAck) Packet** .. csv-table:: :file: ./OSPF/OSPF_Packetdetails5.csv :widths: 10,20,30,10 :header-rows: 1 .. _OSPF_step7: .. tab-set:: .. tab-item:: OSPF Usecases .. csv-table:: :file: ./OSPF/OSPF_Use_Cases.csv :widths: 10,20,30 :header-rows: 1 .. _OSPF_step8: .. tab-set:: .. tab-item:: OSPF Basic Features .. csv-table:: :file: ./OSPF/OSPF_Basic_Features.csv :widths: 10,10,30 :header-rows: 1 .. _OSPF_step9: .. tab-set:: .. tab-item:: OSPF Feature : Link-State Protocol **Link-State Protocol - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature1_Link_State_Protocol_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step10: .. tab-set:: .. tab-item:: OSPF Feature : Hierarchical Design **Hierarchical Design - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature2_Hierarchical_Design_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step11: .. tab-set:: .. tab-item:: OSPF Feature : Fast Convergence **Fast Convergence - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature3_Fast_Convergence_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step12: .. tab-set:: .. tab-item:: OSPF Feature : Cost-Based Metric **Cost-Based Metric - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature4_Cost_Based_Metric_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step13: .. tab-set:: .. tab-item:: OSPF Feature : Supports VLSM and CIDR **Supports VLSM and CIDR - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature5_Supports_VLSM_and_CIDR_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step14: .. tab-set:: .. tab-item:: OSPF Feature : Multicast Updates **Multicast Updates - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature6_Multicast_Updates_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step15: .. tab-set:: .. tab-item:: OSPF Feature : Authentication Support **Authentication Support - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature7_Authentication_Support_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step16: .. tab-set:: .. tab-item:: OSPF Feature : DR BDR Election **DR BDR Election - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature8_DR_BDR_Election_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step17: .. tab-set:: .. tab-item:: OSPF Feature : Equal-Cost Multipath (ECMP) **Equal-Cost Multipath (ECMP) - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature9_Equal-Cost_Multipath_ECMP_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step18: .. tab-set:: .. tab-item:: OSPF Feature : Scalable and Extensible **Scalable and Extensible - Testcases** .. csv-table:: :file: ./OSPF/OSPF_Feature10_Scalable_and_Extensible_TestCases.csv :widths: 10,10,30,20 :header-rows: 1 .. _OSPF_step19: .. tab-set:: .. tab-item:: Reference links * Reference links