Schedule Network Diagram

Schedule Network Diagram Guide for PMI-SP

What is a Schedule Network Diagram?

A Schedule Network Diagram is a graphical representation of the logical relationships (dependencies) between project schedule activities. It serves as a visual roadmap showing how activities connect and the sequence in which they must be performed to complete the project.

Why Schedule Network Diagrams are Important:

1. Visibility of Dependencies - They clearly show how activities relate to each other
2. Critical Path Identification - Help identify the sequence of activities that determine the project duration
3. Constraint Management - Enable visualization of schedule constraints and bottlenecks
4. Risk Assessment - Facilitate identification of schedule risks and potential delays
5. Communication Tool - Provide stakeholders with a clear view of project flow

Common Elements of Schedule Network Diagrams:

- Activities: Represented as boxes or nodes
- Dependencies: Shown as arrows connecting activities
- Milestones: Key events or checkpoints
- Duration Estimates: Time required for each activity
- Float/Slack: Available flexibility in activity timing

Types of Dependencies:

1. Finish-to-Start (FS): Most common - Activity B cannot start until Activity A finishes
2. Start-to-Start (SS): Activity B cannot start until Activity A starts
3. Finish-to-Finish (FF): Activity B cannot finish until Activity A finishes
4. Start-to-Finish (SF): Activity B cannot finish until Activity A starts (rare)

Network Diagram Methods:

1. Precedence Diagramming Method (PDM): Activities shown as boxes (nodes) connected by arrows
2. Arrow Diagramming Method (ADM): Activities shown as arrows, with nodes representing start/end points

Creating a Schedule Network Diagram:

1. Identify all project activities
2. Determine logical relationships between activities
3. Sequence activities based on dependencies
4. Draw the diagram showing these relationships
5. Analyze the diagram for the critical path and potential issues

Critical Path Method (CPM):

The critical path is the longest sequence of activities that must be completed on time for the project to finish on schedule. Activities on this path have zero float, meaning any delay will delay the entire project.

Exam Tips: Answering Questions on Schedule Network Diagram

1. Know Your Terminology: Understand terms like predecessors, successors, leads, lags, float, and critical path

2. Dependency Types: Memorize all four dependency types (FS, SS, FF, SF) and recognize when each is appropriate

3. Critical Path Calculations: Practice forward pass (early start/finish) and backward pass (late start/finish) calculations

4. Float Identification: Be able to calculate and interpret float values for activities

5. Network Logic: Understand how changes to one activity can impact the entire network

6. Common Question Types:
- Identifying the critical path in a given network
- Calculating project duration based on a network
- Determining float for specific activities
- Analyzing impacts of delays or changes
- Recognizing appropriate dependency types for scenarios

7. Diagram Analysis: Practice "reading" network diagrams to extract information quickly

8. Situational Application: Be ready to apply network diagram concepts to real-world project scenarios

9. Multiple Paths: Remember projects can have near-critical paths that require attention

10. Schedule Compression: Understand how fast-tracking (parallel activities) and crashing (adding resources) affect the network diagram

When taking the PMI-SP exam, carefully read each question related to Schedule Network Diagrams. Look for key information about dependencies, durations, and constraints before selecting your answer. Many questions will require calculation, so manage your time efficiently.