What is the major difference between EIGRP and OSPF?

1. OSPF is an Open Protocol whereas EIGRP is a Cisco propriety protocol.

2.  OSPF is merely a link state protocol whereas EIGRP shows characteristics of both link state and distance vector protocol.

3. OSPF calculates the metric using cost but EIGRP uses bandwidth, load, delay and reliability to calculate the metric.

4. Max Hop count of OSPF is unlimited whereas max hop count of EIGRP is100 by default and max255.

 5. OSPF works on DIJKSTERA algorithm but EIGRP work on Bellmen-Ford algorithm.

EIGRP :

1.Distance vector 

2. Fast Convergence

3. Better Timers

4. Multicast224.0.0.10

5. Unequal path load balancing

6. No compatible with multi-vendors Routers environment 

7. Limited network visibility

8. Auto Summarization

OSPF:

1.Link State

2.Slow Convergence 

3.DR/BDR

4. Musticat224.0.0.5

5. Used in Multi-vendor environment  

6. have full network visibility in a area

7. No summarization 

OSPF:1.
use cost as metric.(cost=10^8/bandwidth)2.
use multicast addressing224.0.0.5 &224.0.0.63.
administrative distance =110 EIGRP:1.
Use bandwidth, delay, reliability to calculate metric.2.
multicast address224.0.0.103.
AD=90

The most important difference is that OSPF is open standards and EIGRP is Cisco Proprietary.

OSPF:1.No backup route , every time run SPF algorithm to calculate backup route2.
use multicast addressing224.0.0.5 &224.0.0.63.
administrative distance =1104.
Equal cost load balancing5.
use cost as metric.(cost=10^8/bandwidth) EIGRP:1.
Having backup route and immediately switch if primary fails (primary = successor , backup = feasible successor)2.
multicast address224.0.0.103.
administrative distance=904.
Unequal cost load balancing5.
Use bandwidth, delay, reliability to calculate metric.