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VPN & privacy glossary
Short, plain-language definitions of the terms that come up when you read about VPNs, encryption, censorship, and network privacy. Each entry is 400-600 words and links to deeper reading.
Hysteria vs VLESS Reality
Hysteria 2 is built on QUIC, which runs over UDP; VLESS Reality uses modified TLS, on TCP with Xray's RAW transport. No independent head-to-head test was found. On design, the choice turns on whether your network passes UDP and how much packet loss it has.
Shadowsocks vs Trojan-GFW
Both are censorship-circumvention tools. Shadowsocks is older and more entropy-detectable. Trojan does real TLS handshakes but uses your own certificate.
VLESS Reality vs Shadowsocks
Both target DPI-heavy markets. Shadowsocks (2012) is older and increasingly detected. VLESS Reality (2023) survives where Shadowsocks fails.
VLESS Reality vs Trojan-GFW
Both perform real TLS handshakes. Trojan uses your own certificate; Reality uses a third party's. Reality survives Certificate Transparency comparison; Trojan increasingly does not.
VLESS Reality vs WireGuard
WireGuard is faster and simpler. VLESS Reality survives DPI in censored markets where WireGuard is blocked. Different tools for different networks.
What is active probing
Censorship technique where censors send their own probes to suspected proxy servers to verify the server is or is not a VPN, then block based on the response.
What is Reality (Reality protocol)
A transport for VLESS that performs a real TLS handshake to a real public site, forwarding that site's actual certificate so DPI sees ordinary HTTPS.
What is Shadowsocks
A SOCKS5-style proxy with stream encryption, created in 2012 to bypass China's Great Firewall. Predecessor to VLESS Reality and other modern censorship-circumvention protocols.
WireGuard vs L2TP/IPsec
L2TP is legacy. WireGuard is modern, faster, simpler, and more secure. Use WireGuard. The only reason to consider L2TP is legacy compatibility.
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