New Training: OSPF Foundation Concepts
In this 10-video skill, CBT Nuggets trainer Keith Barker covers the fundamental components and functions of OSPF for IPv4, including link-state advertisements (LSAs), normal areas, network types, summarization, and filtering. Gain an understanding of Type 1, Type 2, Type 3, Type 4, and Type 5 LSAs. Watch this new Cisco training.
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This training includes:
1.3 hours of training
You’ll learn these topics in this skill:
Introducing OSPF Foundations
Router LSAs (Type 1)
DRs, BDRs, and Others
Network LSAs (Type 2)
ABRs and Summary LSAs (Type 3)
ASBR and External LSA Type 5
Type 4 LSAs
OSPF Full Adjacencies
A Brief Introduction to OSPF
OSPF is a core routing protocol. It's primarily used with autonomous systems, and as such, is a basis on which IP routing is performed. OSPF is a basic principle that aspiring network admins need to understand in the same way that system integrators need to understand how a BIOS works.
OSPF stands for Open Shortest Path First. That name should offer a big clue in what this protocol does. OSPF uses a special algorithm for locating the shortest available path between point A and point B in a network. That algorithm is called Dijkstra’s Shortest Path First algorithm. Once that path is identified, networking equipment will use it to route traffic through a network.
Though OSPF is a common protocol, it will differ slightly depending on whether it is being implemented in an IPV4 or IPV6 network. Both IPV4 and IPV6 use different standards of the OSPF protocol.
It's important to note that though OSPF will attempt to utilize the shortest network path for routing traffic, this may not always be the case for software-defined networks. In theory, the shortest path is typically the fastest. Software-defined networks build on top of that idea but instead send traffic through the fastest available path. Sometimes the shortest path may include delays that incur too much latency in communication. In this case, software-defined networks may opt for a longer path instead that offers faster routing.