In this article, we learn about what is dynamic routing, how dynamic routing works, key features, Characteristics, types of dynamic routing protocols, advantages of dynamic routing and disadvantages of dynamic routing.
What is Dynamic routing
In computer networking, dynamic routing is an adaptive technique where routers automatically pick up, exchange, and update network path information without a network administrator’s active assistance. Static routing, in which routes are manually configured, differs greatly from this procedure. For data packets to get from their source to their destination effectively, dependably, and on schedule, dynamic routing is essential.
Routing that automatically adapts to variations in traffic or network architecture is known as dynamic routing. In order to locate all networks within the network, maintain consistent routing tables, and identify the most effective route for packets to take in order to get to their destinations, routers use routing protocols. Dynamic routing protocols allow routers to interact with their neighbors when a network isn’t physically connected to them. They do this by exchanging and updating information about known networks in their routing tables.
You can also read Cisco VLAN Troubleshooting Commands And VLAN Issues
How Dynamic Routing Works
The core functionality of dynamic routing revolves around the following steps:
Routing Protocols: To interact with one another, routers use routing protocols like RIP, OSPF, and BGP. These protocols control the distribution and sharing of data among network nodes.
Routing Table Updates: Routers automatically update their routing tables, which are logical data structures that store routes, by exchanging information about network paths. The process may begin with a manual start for the table of the first router, but it thereafter moves forward automatically using dynamic routing algorithms.
Path Selection: Using a variety of measures, such as hop count, link speed, bandwidth, delay, or total cost, routers determine the optimal route to a destination.
Adaptation to Changes: The dynamic routing protocol recognizes when a network condition changes, such as when a link fails, there is congestion, or new devices are added. After that, it automatically notifies every router about the occurrence, causing them to transmit fresh update messages and recalculate their routes. Dynamic routers can reroute traffic in real-time this capacity. For instance, if a path like R1->R2->R5->R9->R10 fails at R9, it may dynamically create a new way like R1->R2->R5->R8->R10. Performance and continuity are thus guaranteed.
Network Convergence: Network convergence is the result of this information sharing and recalculating process. In this condition, the network’s routers all function with a precise and consistent representation of the updated topology. In order to reduce the amount of time that routers may make poor routing choices, rapid convergence is preferred.
Key Features and Characteristics
Dynamic routing offers several distinguishing characteristics:
- Automatic It requires minimal administrator input to discover and adjust routes.
- Adaptive It can dynamically change paths in response to evolving network conditions.
- Scalable It is well-suited for large, complex, and constantly changing networks, making management easier than with static routing.
- Efficient It finds the most optimal path based on predefined metrics.
- Resilient It automatically recalculates the best route around network outages, ensuring traffic continues to flow even if primary links fail.
- Load Balancing Many dynamic routing protocols can automatically load balance traffic across multiple equal-cost routes, and some, like EIGRP, can even balance across unequal-cost paths.
You can also read IP Connectivity Requirements, How it Works, and Importance
Types of Dynamic Routing Protocols
Dynamic routing protocols are generally categorized into three main types:
Distance-Vector Protocols
- These protocols use “distance,” which is frequently determined by hop count, to identify the optimal path.
- Sometimes referred to as “routing by rumour,” they occasionally forward their complete routing table to neighbors who are directly connected.
- RIP (Routing Information Protocol) is one example, with a maximum hop count of 15. Another example is IGRP.
- Distance-vector protocols use techniques like Split Horizon, Route Poisoning/Poison Reverse, Triggered Updates, and Hold-down Timers to reduce the possibility of routing loops.
Link-State Protocols
- By employing these protocols, routers create a comprehensive topological map of the network (or a designated region), giving every router in that region a uniform picture.
- When the network topology changes, they issue Link-State Advertisements (LSAs), which are tiny, incremental updates.
- They may use cost, latency, or bandwidth as measurements.
- IS-IS and OSPF (Open Shortest Path First) are two examples. To choose the best course of action, OSPF employs algorithms such as Dijkstra’s Shortest Path First.
Hybrid Protocols
- These protocols incorporate elements of link-state and distance-vector methodologies.
- Instead of using recurring broadcasts, they usually use distance vectors with more precise measurements and initiate updates in response to topology changes.
- Cisco’s proprietary EIGRP (Enhanced Interior Gateway Routing Protocol) is one example. The Diffusing Update Algorithm (DUAL), which EIGRP uses for path selection and loop-free routing, combines load, bandwidth, latency, and dependability in its metrics.
Advantages of Dynamic Routing
- Ease of Configuration (for large networks) While initial setup can be complex, dynamic routing is generally easier to configure and manage in large, complex networks as routes are learned automatically.
- Automatic Rerouting It automatically finds alternative routes if a primary path fails, enhancing network resilience.
- Optimized Path Selection It is highly effective at selecting the best route to a destination and discovering remote networks.
- Scalability It is suitable for large, intricate, and constantly changing network environments.
- Reduced Manual Intervention It significantly reduces the need for manual configuration and updates, leading to fewer human errors.
- Reliability Sharing network information among routers makes them more reliable and efficient.
Disadvantages of Dynamic Routing
- Higher Resource Usage Dynamic routing protocols consume more network bandwidth, router CPU, and RAM due to the continuous exchange of routing updates and complex calculations. This often necessitates more powerful hardware.
- Lower Security It generally provides less security than static routing because it tends to reveal all known network information.
- Configuration Complexity While automating route learning, the initial setup and troubleshooting of dynamic routing protocols can be more intricate than static routing.
- Less Administrative Control The “best route” is determined by the routing protocol’s algorithm, giving administrators less direct control over path selection.
- Higher Maintenance It can require higher maintenance compared to static protocols.
You can also read Basic VLAN Configuration: Guide To Setting Up A Virtual LAN