Core Concepts: Multiplexing (Mux)¶

Multiplexing, or "Mux," is a powerful feature in protocols like VLESS and VMess that significantly improves performance by reusing a single underlying TCP connection for multiple data streams.

What is Mux?¶

Imagine a single-lane road versus a multi-lane highway.

• Without Mux (Single Lane): Every time your browser wants to download a new piece of a website (an image, a script, etc.), it has to create a brand new connection. This involves a slow and costly process called a TCP and TLS handshake for every single request.

• With Mux (Multi-Lane Highway): The client opens one single, robust connection to the server (the highway). Then, all subsequent data streams (the cars) travel through this existing connection simultaneously.

Why is it Important?¶

Enabling Mux has several key benefits:

• Reduced Latency: By eliminating the need for repeated handshakes, Mux drastically reduces the time it takes to start new requests. This is especially noticeable on websites with many small assets.
• Improved Throughput: It leads to more efficient use of the network connection, which can improve overall download and upload speeds.
• Evasion Potential: In some cases, the traffic pattern of a Mux-enabled connection can look different from standard VPN traffic, which may help with avoiding detection.

Enabling Mux with python-v2ray¶

Our library provides two flexible ways to enable and configure Mux.

Method 1: Per-Config (via URI)¶

This is the most precise method. The custom mvless protocol scheme allows you to enable Mux and set its concurrency directly within the configuration link.

from python_v2ray.config_parser import parse_uri

# Example mvless URI with Mux enabled
uri = "mvless://UUID@example.com:443?mux=ON&muxConcurrency=8&type=ws#MyMuxConfig"

params = parse_uri(uri)

if params:
    print(f"Mux Enabled: {params.mux_enabled}")
    print(f"Mux Concurrency: {params.mux_concurrency}")

Mux Enabled: True
Mux Concurrency: 8

Method 2: Global Setting (via ConnectionTester)¶

You can apply a default Mux configuration to all Xray-compatible proxies that don't already have Mux enabled in their URI. This is done by passing a mux_config dictionary to the test_uris method.

from python_v2ray.tester import ConnectionTester
from python_v2ray.config_parser import parse_uri

# Define your global Mux settings
global_mux_settings = {"enabled": True, "concurrency": 8}

# This standard vless config does NOT have Mux defined in its URL
uris = ["vless://UUID@example.com:443?type=ws#StandardVless"]
parsed_configs = [parse_uri(uri) for uri in uris]

# Initialize the tester
tester = ConnectionTester(vendor_path="./vendor", core_engine_path="./core_engine")

# Pass the global config to the tester
# The tester will now apply these Mux settings to the 'StandardVless' config
results = tester.test_uris(
    parsed_params=parsed_configs,
    mux_config=global_mux_settings
)

Priority Rules¶