Background
A university campus network throttles bandwidth to 30 Mbps (about 3.75 MB/s), which makes downloading large files like games and models painfully slow. However, I accidentally discovered that in rare cases, certain resources are not throttled — for example, downloading installers from app stores or installing Python packages via Anaconda can reach around 20 MB/s, which is more than enough.
Recently, I came across a post about using the tool Download CDN Redirect IPv6 Toolkit (Steam/EPIC/BattleNet/UbiConnect/XboxPC) – Dogfight360 by the developer of Dogfight360 – Yuyicheng Personal Blog, which redirects Steam download requests to IPv6-capable CDNs and achieves full-speed downloads. After testing, it indeed works.
That gave me an idea: since IPv6 traffic isn’t throttled, is there a way to send all traffic over IPv6 and bypass the limit?
From what I’ve learned, some universities don’t charge for IPv6 traffic, so you can try this approach too. But if your campus network doesn’t support IPv6 or also throttles it, this method won’t help.
To test whether IPv6 is supported:
- IPv6 test (ipip.net)
- Or run this in the command line:
ping 2001:4860:4860::8888and see if it responds.
Principle
Use an IPv6 node to forward all local traffic over IPv6, thereby bypassing the speed limit. (Yes, it’s the same thing used for circumventing censorship.)
Specific Methods
Find a node that supports IPv6 directly
I recall seeing some “airports” (proxy providers) with this kind of node. If you’re interested, you can search for them yourself. Or maybe I misremembered.
Set up your own node
You’d better have a spare VPS. Make sure it supports IPv6.
Reference:
Then export the subscription and use it in V2rayN.
If you use Clash on a daily basis, you can use the following website to convert vmess nodes to a Clash configuration file.
v2ray to Clash node - v2rayse.com
Remember to enable the IPv6 option in Clash settings.
References
- Achieving Campus Network IPv6 Free-Traffic Internet Access and Circumventing Censorship | V2ray Tutorial: X-ui and v2rayN ~ Polaris Network (jixing.one)
- An Attempt to Bypass Campus Network Quotas Using IPv6 - Zhihu (zhihu.com)
- Up to 18 MB/s! How to Break the 3.6 MB/s TJ-WIFI Speed Limit Curse? (qq.com)