| Critical Path is another technique to do the Schedule | | | | Delaying activities on the critical path is as good as |
| Network Analysis. | | | | delaying the project duration! |
| Critical path is defined as the longest duration path | | | | There are 2 ways in which float of an activity can be |
| through a network diagram and determines the | | | | calculated. But before that let me inform you that first |
| shortest time to complete the project. We will shortly | | | | step in critical path method is to identify the Critical |
| learn on how to identify a critical path in a network. | | | | Path of the Network. Once the critical path is identified, |
| Float is another concept, which is quiet important in | | | | calculate the start date and end date of each of the |
| understanding the critical path. Float is calculated once | | | | activities on the critical path. |
| the network diagram is ready. There are three kind of | | | | As we have seen earlier, the float of the activities on |
| float that can be calculated. The first being the Total | | | | the critical path is zero…so they represent the overall |
| Float, which is the amount of time an activity can be | | | | project duration. Now, that you know the Project |
| delayed without delaying the project end date or an | | | | duration.Either you can go through the network starting |
| intermediary milestone. | | | | with time zero and keep on calculating the time |
| The second type of float is Free Float which is the | | | | required to complete each of the activity till you reach |
| amount of time an activity can be delayed without | | | | the last activity of the Project. This is also called |
| delaying the early start date of its successor(s) | | | | Forward pass. The starting time for each of the |
| activities. | | | | activity in this approach is called “Early Start” |
| The last type is Project Float which is the amount of | | | | and end time for each activity is called the “Early |
| time a Project can be delayed without delaying the | | | | Finish”. |
| externally imposed project completion date required by | | | | Or you can travel through the network from the |
| the customer or previously committed by the Project | | | | project end date and calculate the time required to |
| Manager.You can think of float as a cushion time | | | | complete each activity. This is called backward pass. |
| available to complete an activity. Float is also called | | | | The end date in this approach is called the Late Finish |
| slack.Now, let me ask you. What is the slack of the | | | | and the start date of the activity in this approach is |
| activities on the critical path? The answer is Zero. | | | | called the Late Start. |
| Because, there is no scope to delay activities in the | | | | The float of the activity is either the difference |
| critical path. Critical Path actually represents the | | | | between the Early Start and Early finish or the |
| Project duration. They actually add together to the | | | | difference between the Late Start and Late finish. |
| Project duration, so where is the scope for the delay? | | | | Both the differences work out to be the same. |