i want to learn about the protocols of networking like ospf , egb , egirp , the division of static and dynamic routing

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Network routing is the process of selecting paths in a network to send data packets. There are two main types of routing: static and dynamic. Static routing involves manually configuring fixed paths between routers. It's simple to implement for small networks and uses no additional resources. Dynamic routing, on the other hand, uses protocols like OSPF, EIGRP, and BGP to automatically learn and adapt to network changes. This makes it more scalable for large networks. In our diagram, the red arrow represents a static route that must be manually configured, while the green arrows show dynamic routes where routers automatically exchange routing information. Interior Gateway Protocols or IGPs are used for routing within a single autonomous system. OSPF, or Open Shortest Path First, is a link-state routing protocol where each router builds a complete map of the network topology. It uses Dijkstra's algorithm to calculate the shortest path to each destination based on cost, which is typically derived from bandwidth. OSPF routers exchange Link State Advertisements or LSAs to share information about their connected links. OSPF uses areas for scalability, with Area 0 serving as the backbone. EIGRP, or Enhanced Interior Gateway Routing Protocol, is an advanced distance-vector protocol that exchanges routing tables with neighbors. It uses the Diffusing Update Algorithm, or DUAL, to prevent routing loops and achieve fast convergence. EIGRP uses a composite metric based on bandwidth, delay, reliability, and load to determine the best path. Border Gateway Protocol, or BGP, is the routing protocol of the internet. Unlike interior gateway protocols like OSPF and EIGRP that operate within a single autonomous system, BGP is an exterior gateway protocol used between different autonomous systems. BGP is a path-vector protocol that stores the complete path of autonomous system numbers that a route traverses. This helps prevent routing loops in the complex internet topology. BGP makes routing decisions based on policies rather than just metrics. It uses various attributes for path selection, including local preference, AS path length, origin type, multi-exit discriminator, and preferring external BGP routes over internal ones. BGP uses TCP port 179 for reliable communication between peers. While it has slower convergence compared to IGPs, BGP is designed for stability and scalability across the global internet. In our diagram, we can see three autonomous systems exchanging routing information via BGP, with each AS advertising its networks along with the AS path information. When choosing a routing protocol, it's important to consider several factors. Let's compare the main protocols we've discussed. OSPF is a link-state protocol that uses cost as its metric and converges quickly, making it suitable for enterprise networks. EIGRP is a hybrid protocol with very fast convergence that uses a composite metric based on bandwidth, delay, reliability, and load. BGP is a path-vector protocol used primarily for internet routing between service providers, with slower convergence but greater stability. Static routing is manually configured, has no automatic convergence, but works well for small, simple networks. The choice of routing protocol depends on several factors: network size and complexity, convergence speed requirements, administrative control needs, and hardware capabilities. As networks grow from small to large, the routing requirements typically progress from static routing to interior gateway protocols like OSPF or EIGRP, and finally to BGP for connecting to other autonomous systems. To summarize what we've learned about network routing protocols: Static routing involves manually configuring routes and works well for small, simple networks with minimal changes. Dynamic routing uses protocols to automatically learn and adapt to network changes, making it suitable for larger, more complex networks. Interior Gateway Protocols like OSPF and EIGRP operate within a single autonomous system. OSPF is a link-state protocol that builds a complete network map, while EIGRP is a hybrid protocol that exchanges routing tables with neighbors. Border Gateway Protocol, or BGP, is the exterior gateway protocol that connects different autonomous systems and forms the backbone of internet routing. When selecting a routing protocol, consider factors such as network size, complexity, convergence requirements, and administrative control needs. As networks grow in size and complexity, routing solutions typically progress from static routing to IGPs like OSPF or EIGRP, and finally to BGP for connecting to other autonomous systems.