EGP / IGP :: Distance Vector / Link State :: Dynamic Routing Protocols :: OSPF EIGRP BGP RIP IS-IS

Summary

This video provides an in-depth exploration of dynamic routing protocols, covering Interior Gateway Protocols (IGPs) like RIP, EIGRP, OSPF, and IS-IS, as well as Exterior Gateway Protocols (EGPs) like BGP. The video distinguishes between IGPs, used within a single autonomous system for faster, more responsive routing, and EGPs, which share routes between autonomous systems with a focus on stability, security, and control. Additionally, it explains the differences between distance vector protocols (RIP, EIGRP) and link state protocols (OSPF, IS-IS), highlighting the trade-offs in speed, resource usage, and failure recovery. The video concludes by offering guidance on selecting the best protocol for different network environments.

Takeaways

• 😀 Dynamic routing protocols enable routers to automatically share routes with one another.
• 😀 There are two main types of dynamic routing protocols: Interior Gateway Protocols (IGPs) and Exterior Gateway Protocols (EGPs).
• 😀 IGPs, such as RIP, EIGRP, OSPF, and ISIS, are designed for use within a single autonomous system (AS).
• 😀 EGPs, like BGP, are used for route sharing between different autonomous systems, such as between companies and ISPs.
• 😀 IGPs are optimized for speed and responsiveness, quickly adjusting routes in the event of a failure.
• 😀 EGPs are designed for stability and security, often limiting updates to avoid flooding the internet with minor failure events.
• 😀 BGP allows companies to influence routing decisions and manage their IP address space with more control than IGPs.
• 😀 Link state protocols, like OSPF and ISIS, have knowledge of the entire network topology and converge quickly in case of a failure.
• 😀 Distance vector protocols, such as RIP and EIGRP, only know about their direct neighbors and can be slower to react to failure events.
• 😀 EIGRP is considered a hybrid protocol because it combines features of both distance vector and link state protocols.
• 😀 Modern routers can handle the additional resource costs of link state protocols, making them more feasible for today's networks.

Q & A

What is the main purpose of dynamic routing protocols?

The main purpose of dynamic routing protocols is to allow routers to automatically share routes with each other, making network management more efficient by reducing the need for manual updates.

What are the main differences between IGPs and EGPs?

IGPs (Interior Gateway Protocols) operate within a single autonomous system (AS), such as RIP, EIGRP, OSPF, and ISIS, and are tuned for speed and responsiveness. EGPs (Exterior Gateway Protocols), like BGP, operate between different ASes, focusing on stability, security, and control of route selection across the internet.

What defines an Autonomous System (AS)?

An Autonomous System (AS) is a set of routers or networks under a single administrative control, usually within one organization or a group of interconnected companies, where routing is managed internally.

How do IGPs handle route sharing within a network?

IGPs, such as EIGRP or OSPF, allow routers within the same AS to share routes and respond quickly to network changes, ensuring that if a failure occurs, routers can rapidly update their routes to maintain connectivity.

Why are EGPs like BGP designed for stability and security?

EGPs are designed for stability and security because they manage routes between different autonomous systems, and they need to prevent unnecessary updates from propagating through the internet. BGP, for example, helps control which routes are accepted and ensures the integrity of the routing process.

What is the key difference in how IGPs and EGPs respond to failures?

IGPs are designed to respond quickly to failures within an AS, with routers rapidly adjusting routes to ensure continuity. EGPs, on the other hand, are slower to react to failures and typically limit the scope of updates to avoid flooding the entire internet with small issues.

What is the function of BGP in internet routing?

BGP (Border Gateway Protocol) is the primary EGP used on the internet to exchange routing information between different autonomous systems. It helps control the flow of traffic by determining the best path based on policies, preferences, and network stability.

What is the advantage of Link State Protocols over Distance Vector Protocols?

Link State Protocols, such as OSPF and ISIS, have a complete map of the network topology, which allows them to converge faster and better handle network changes. Although they require more resources, they can quickly adapt to failures by using alternative routes.

What are the characteristics of Distance Vector Protocols?

Distance Vector Protocols, such as RIP and EIGRP, have knowledge only of the next hop router. They are simpler and use fewer resources but are slower to converge and less efficient at reacting to network failures compared to Link State Protocols.

Why is EIGRP considered a hybrid protocol?

EIGRP is considered a hybrid protocol because it combines elements of both Distance Vector and Link State protocols. It uses features like faster convergence and partial network knowledge, which are typically associated with Link State protocols, while maintaining the simplicity of Distance Vector protocols.