Speeding Up Your Network with Google BBR

Google’s BBR (Bottleneck Bandwidth and Round-trip propagation time) is a congestion control algorithm that can significantly improve network performance. In this post, I’ll guide you through enabling BBR on your Linux system to boost network speeds.

What is BBR?

BBR is a TCP congestion control algorithm developed by Google that optimizes network throughput and reduces latency. Unlike traditional loss-based congestion control algorithms, BBR uses bandwidth and round-trip time measurements to build a model of the network, allowing for better utilization of available bandwidth.

Prerequisites

Before we begin, ensure you have:

• A Linux system with root access
• A kernel version 4.9 or newer

Step 1: Check if BBR is available in your kernel

First, let’s check if BBR is available in your system:

sudo sysctl net.ipv4.tcp_available_congestion_control

If BBR is available, you should see something like:

net.ipv4.tcp_available_congestion_control = reno cubic bbr

If BBR is not listed, you may need to load the module:

sudo modprobe tcp_bbr

Verify the module is loaded:

lsmod | grep bbr

Step 2: Configure the system to use BBR

Now, we need to configure the system to use BBR. Create or edit the sysctl configuration file:

sudo nano /etc/sysctl.conf

Add the following lines at the end of the file:

net.core.default_qdisc = cake
net.ipv4.tcp_congestion_control = bbr

Note: The cake qdisc (queue discipline) works well with BBR. Alternatively, you can use fq if cake is not available.

Step 3: Apply the changes

Apply the new settings:

sudo sysctl -p

Step 4: Verify BBR is enabled

To confirm BBR is now active:

sudo sysctl net.ipv4.tcp_congestion_control

You should see:

net.ipv4.tcp_congestion_control = bbr

Benefits of Using BBR

• Higher throughput: BBR can achieve higher network throughput compared to other congestion control algorithms.
• Lower latency: It reduces bufferbloat and maintains lower latencies.
• Better performance on lossy networks: BBR handles packet loss more efficiently than traditional algorithms.
• Improved experience: Faster downloads, smoother streaming, and better overall connection stability.

Conclusion

By enabling Google’s BBR algorithm on your Linux system, you can significantly improve your network performance. BBR is particularly effective for high-bandwidth, high-latency connections, but it can benefit almost any network environment.

Remember that kernel updates may reset these settings, so you might need to reapply them after major system updates.