Difference between Hierarchical and Flat routing protocol

1. Hierarchical Routing Protocol:
Hierarchical Routing is the method of routing in networks that is based on hierarchical addressing. Most transmission control protocol, Internet protocol (TCPIP). Routing is based on two level of hierarchical routing in which IP address is divided into a network, person and a host person. Gateways use only the network a person tell an IP data until gateways delivered it directly. 
It addresses the growth of routing tables. Routers are further divided into regions and they know the route of their own regions only. It works like a telephone routing. 
Example –
City, State, Country, Continent. 

2. Flat Routing Protocol:
In flat routing protocol, if any node needs to transmit data, it first searches for a valid route to the base station and then transmits the data. Nodes to the base station may drain their energy quickly. 
They are the flat networks in which every incoming packet is sent out on every outgoing line except the one it arrived on. Vast numbers of duplicate packets are generated. It is good for small networks and offers high reliability. 
Example –
Routing Information Protocol, Interior Gateway Routing Protocol. 

Difference between Hierarchical and Flat Routing Protocol :

Hierarchical Routing Protocol	Flat Routing Protocol
It is simple but non-optimal routing.	Routing can be made optimal but with an added complexity.
It is a Channel Reservation-based scheduling.	It is a Contention-based scheduling.
Collisions is avoided.	Collisions over-head in attendance.
Overhead of cluster information all over the network.	Routes form only in the regions that have data for transmission.
Fair channel allocation.	Fairness is not guaranteed.
In this, Energy Dissipation is consistent.	In this, Energy Dissipation depends on traffic patterns.

Hierarchical Routing Protocol:
Advantages:

1. Scalability: Hierarchical routing protocols are highly scalable as they divide the network into smaller segments or areas, reducing the number of routing tables and updates required for each router. This makes the network more efficient and reduces the overall traffic on the network.
2. Better Traffic Control: Hierarchical routing protocols can handle traffic more effectively than flat routing protocols. The hierarchical structure allows for better traffic control and avoids unnecessary routing updates and loops.
3. Easy to Manage: The hierarchical structure of these protocols makes them easier to manage and maintain. The network can be divided into manageable segments, making it easier to troubleshoot and diagnose issues.

Disadvantages:

1. Complexity: Hierarchical routing protocols can be more complex than flat routing protocols. The additional layers and segments require more configuration and can be more difficult to implement.
2. Latency: The additional layers and segments can introduce latency into the network. This can cause delays in data transmission, which can be problematic for real-time applications.

Flat Routing Protocol:
Advantages:

1. Simplicity: Flat routing protocols are simpler than hierarchical protocols. They are easier to configure and require less maintenance.
2. Lower Latency: Flat routing protocols have lower latency than hierarchical protocols. This is because there are no additional layers or segments that introduce delays.
3. Flexibility: Flat routing protocols are more flexible than hierarchical protocols. They can be used in a variety of network topologies and can adapt to changes more easily.

Disadvantages:

1. Limited Scalability: Flat routing protocols are not as scalable as hierarchical protocols. As the network grows, the routing tables and updates required for each router can become unmanageable.
2. Less Traffic Control: Flat routing protocols have less traffic control than hierarchical protocols. This can lead to unnecessary routing updates and loops, which can increase network congestion and reduce network efficiency.
3. Difficult to Troubleshoot: Flat routing protocols can be difficult to troubleshoot and diagnose issues. With no hierarchical structure, it can be difficult to isolate issues and determine their source.