Windows VPN Guide: Full Tunnel vs Split Tunneling Compared

Choosing a Windows VPN is rarely about which client to install. Two questions matter far more: which apps should go through the route, and whether that route holds up during evening peak hours. On desktop these become two independent choices — full tunnel versus split-tunnel rules — layered on top of two ways of capturing traffic, the system proxy and a TUN virtual adapter. Below we compare access layers, clients and protocols, game and office app compatibility, and autostart, then close with an order for picking routes and plans by use case.

Full Tunnel and Split Tunneling: What Each Mode Covers

Full tunnel sends every packet outside the local network through the route, DNS resolution included. The upside is zero rule maintenance — install it and go. The cost is that local sites also take the long way round, so real-world speed depends on the quality of the return path.

Split tunneling (rule mode) decides by domain, IP range, process or geo database: requests that match a direct rule use the local connection, everything else goes through the route. Local sites connect directly, overseas sites use the route, and two DNS resolvers each handle their own side. The finer the rules, the more maintenance they need — but the difference in everyday browsing is noticeable.

The key difference between the two comes down to DNS and UDP. Under system proxy mode, DNS is usually resolved by the application itself, so queries land on the local ISP; in TUN mode the client takes over DNS and, with a mechanism such as fake-ip, resolution stays consistent with the exit. To check your current exit, open the What Is My IP page and see whether the region matches the route label you selected.

Three Common Access Layers on Windows

Windows has no single switch. Different clients capture traffic at different layers, and coverage varies widely. The table below lists three common approaches by access layer.

The access layer only decides which traffic gets captured; the route type decides how that traffic travels. Direct connects straight from the local exit to the destination; relay forwards through a third location first, which is cheaper but shares bandwidth; IEPL runs over a dedicated international Ethernet channel that does not compete for public internet egress, so evening peak stability is usually better — at a higher price.

Clients and Protocols: Four Checks After Importing a Subscription

Windows clients fall into two broad groups: system-level VPN clients, and rule-based clients that import a subscription link. Common examples of the latter include v2rayN, Clash Verge Rev and NekoRay — different interfaces, same flow: copy the subscription link, create a subscription, update nodes, select a route. On protocol support, Shadowsocks, VMess, Trojan and VLESS are the baseline; Hysteria2 and TUIC run over QUIC and need a newer core version.

• ✅ Subscription pulled in full: the node count matches the route list, and a manual update shows new nodes.
• ✅ Rules are working: open a local site and the connection page should show DIRECT rather than the route.
• ✅ DNS is captured: in TUN mode, DNS queries should point to the client, not the local ISP.
• ✅ Auto-connect is enabled: otherwise you have to click it manually after every restart.
• ❌ Don't run two proxy clients at once: the system proxy and TUN fight over the same traffic, and the usual symptom is a connection that works but pages that won't load.
• ❌ Don't post your subscription link in public: the link works as an account credential.

No protocol is universally better; the differences lie in transport and in the situations each one suits.

Game and Office App Compatibility

Most games ignore the Windows system proxy setting, so a client that only sets the system proxy has no effect on them at all. To route a game, you need TUN mode to capture all traffic, or a client that supports per-process rules where you can point at the game executable. Games with anti-cheat are sensitive to virtual adapters, so test in single-player mode first to confirm the game still launches.

UDP is the second hurdle. Voice chat and real-time matches run on UDP and must be allowed in your rules. Hysteria2 and TUIC are QUIC-based protocols, so on networks where UDP is rate-limited they are actually less stable than TCP-based options such as VLESS and Trojan.

In office settings the conflicts come mostly from routing. With a corporate VPN and a subscription client running at the same time, internal domains can be sent through the route by split rules, and the symptom is intranet systems that won't open. Printers and NAS devices on the LAN are the same story: exclude private network ranges in your rules.

rules:
  - DOMAIN-SUFFIX,corp.internal,DIRECT
  - IP-CIDR,10.0.0.0/8,DIRECT,no-resolve
  - IP-CIDR,172.16.0.0/12,DIRECT,no-resolve
  - IP-CIDR,192.168.0.0/16,DIRECT,no-resolve
  - GEOIP,CN,DIRECT
  - MATCH,PROXY

Rules match from top to bottom and stop at the first hit. Putting internal domains and private ranges first keeps them from being caught by geo rules further down.

Autostart and Background Running

There are three ways to start on boot, in ascending order of reliability.

1. The client's built-in launch-at-login and auto-connect. Simplest to set up; the drawback is that when the client starts slowly, network-dependent apps fire off their requests first.
2. Windows Task Scheduler. Set the trigger to at logon and tick run with highest privileges, and TUN mode no longer needs a permission prompt on every start.
3. Run TUN as a service. Some clients can install a service, which the system starts before logon — a good fit for machines that stay on for long periods.

If the tray icon says connected after boot but the browser can't open pages, first check whether the proxy switch in Windows settings is stuck on an address written by a previous crash. When a client crashes it has no time to reset the system proxy to direct, and the leftover value stays in force until you turn it off manually.

Choosing a Route by Use Case: Decision Order

Reduced to a single decision chain, the options above rarely lead you wrong if you work through them in order.

1. Start with coverage. Browser only? The system proxy is enough. Whole machine? Choose TUN.
2. Then pick the mode. Full tunnel if you want zero fuss; split tunneling if you visit a lot of local sites and care about speed.
3. Then choose the exit region. Pick by where the service you need is located — physical distance is not the same as speed, and the quality of the return path matters more.
4. Then the route type. IEPL dedicated lines for stability at peak hours, relay if the budget is tight, direct for short tasks.
5. Then the protocol. Games and voice need UDP, so favour protocols that support it; for browsing only, TCP- and TLS-based options such as VLESS and Trojan are less trouble.
6. Finally the plan. Pick by your actual monthly usage among the three tiers: ¥9.9/60GB, ¥18/250GB and ¥28/500GB. If your usage is irregular, switch to a data pack starting at ¥158/300GB — use it until it runs out, it doesn't expire.

VPNUJ's specs make a useful reference: 110+ countries, 160+ routes, no limit on simultaneous devices, sign-up needs only a username and password with no email address, and the privacy stance is no logging.

This article deliberately lists no speed-test numbers. The same route performs very differently in different regions and at different times of day, so someone else's screenshot tells you little. A more reliable approach is to fix the access layer and route type in the order above, then verify each item on your own network.