Network Throughput Calculator
Calculate TCP throughput, analyze network performance, and estimate file transfer times based on network parameters and conditions.
Network Throughput Calculator
Information
Network Throughput Overview
Network throughput refers to the amount of data successfully transmitted through a network connection within a given time period, typically measured in megabits per second (Mbps) or gigabits per second (Gbps). It is a key metric for measuring network performance and directly affects data transmission efficiency and user experience.
Key Metrics
- Link Bandwidth: Theoretical maximum transmission rate of network connection
- TCP Throughput: Actual transmission rate considering protocol overhead
- Effective Payload Rate: Net data transmission rate excluding all protocol headers
- Bandwidth Utilization: Ratio of actual throughput to link bandwidth
Influencing Factors
- Network Latency (RTT): Round-trip time affects TCP window efficiency
- Packet Loss Rate: Packet loss causes retransmission, reducing effective throughput
- TCP Window Size: Limits the amount of data transmitted simultaneously
- Protocol Overhead: Bandwidth consumed by protocol headers at various layers
- Network Congestion: Competition effects when multiple users share bandwidth
What is Throughput
Network throughput refers to the amount of data successfully transmitted through a network connection within a given time period, typically measured in megabits per second (Mbps) or gigabits per second (Gbps). It is a key metric for measuring network performance and directly affects data transmission efficiency and user experience.
Link Bandwidth: Theoretical maximum transmission rate of network connection
TCP Throughput: Actual transmission rate considering protocol overhead
Effective Payload Rate: Net data transmission rate excluding all protocol headers
Bandwidth Utilization: Ratio of actual throughput to link bandwidth
Network Latency (RTT): Round-trip time affects TCP window efficiency
Packet Loss Rate: Packet loss causes retransmission, reducing effective throughput
TCP Window Size: Limits the amount of data transmitted simultaneously
Protocol Overhead: Bandwidth consumed by protocol headers at various layers
Network Congestion: Competition effects when multiple users share bandwidth
How to Use
This calculator helps you analyze network throughput performance, identify transmission bottlenecks, and provide optimization recommendations. Please follow these steps:
Enter Link Bandwidth: Set the nominal bandwidth value of network connection
Set Round-Trip Time (RTT): Enter network latency time
Configure Packet Loss Rate: Enter network packet loss percentage
Specify File Size: Enter the amount of data to be transmitted
Adjust Advanced Parameters: Modify MTU, overhead and other parameters as needed
Click Calculate: Get detailed throughput analysis results
Formula
Network throughput calculation involves multiple factors. The following are the main calculation formulas and principle explanations:
MSS: Maximum Segment Size, usually MTU minus IP and TCP header size
RTT: Round-Trip Time, affects the efficiency of TCP acknowledgment mechanism
p: Packet loss rate, expressed as decimal (e.g., 0.01 represents 1%)
BDP: Bandwidth-Delay Product, equals bandwidth multiplied by RTT
Window Size: TCP window size, limits the amount of unacknowledged data
Applications
Network throughput calculator is suitable for various network planning, optimization and troubleshooting scenarios:
Quickly identify network transmission bottlenecks, improve troubleshooting efficiency
Scientifically evaluate network performance, provide data support for capacity planning
Optimize TCP parameter configuration, maximize network utilization
Quantitative analysis of transmission performance, support technical decision making
Educational training auxiliary tool, enhance theoretical understanding
Tips
Based on calculation results, the following are practical recommendations for improving network throughput performance:
FAQ
Why is actual throughput always lower than link bandwidth?
Actual throughput is limited by multiple factors: TCP protocol overhead, window limitations caused by network latency, retransmissions due to packet loss, and bandwidth occupied by protocol headers at various layers. These factors together determine the effective data transmission rate.
How does TCP window size affect transmission performance?
TCP window size limits the amount of data the sender can send before receiving acknowledgment. If the window is too small, the sender will frequently wait for acknowledgments and cannot fully utilize network bandwidth. The ideal window size should be at least equal to the Bandwidth-Delay Product (BDP).
What is Bandwidth-Delay Product (BDP)?
BDP is the product of bandwidth and round-trip time, representing the amount of data that can be accommodated in the network pipeline. It is an important reference for setting TCP buffer size to ensure the network pipeline remains fully loaded.
How significant is the impact of packet loss rate on throughput?
Packet loss rate has a significant impact on throughput. According to the Mathis formula, throughput is inversely proportional to the square root of packet loss rate. Even a small packet loss rate (such as 0.1%) can cause a significant drop in throughput, especially in high-latency networks.
How to choose the appropriate MTU size?
MTU size affects transmission efficiency. Larger MTU can reduce protocol overhead but may increase packet loss risk. Standard Ethernet MTU is 1500 bytes, Jumbo Frames can reach 9000 bytes. Selection should consider the support of all devices on the network path.
When calculation results show multiple bottlenecks, which should be prioritized?
Priority should be given to solving the most restrictive bottleneck. Usually in the following order: 1) Network quality issues (high packet loss rate); 2) TCP window size limitations; 3) Protocol overhead optimization. After solving the main bottleneck, the impact of other limiting factors will become more apparent.