Что такое маршрутизация в VPN: от пакета до сервера и обратно
Routing in a VPN is the process that determines which network interfaces and nodes your internet traffic will traverse after connecting to the VPN. Routing rules decide which data goes through the encrypted tunnel and which goes directly to your ISP. Flexible routing allows, for example, work traffic to go through the VPN while local traffic stays direct, improving speed. KelVPN uses modern routing mechanisms, including split tunneling and automatic best-node selection.
1. What Is Routing in Computer Networks
Routing is the process of choosing a path for network packets to travel from source to destination. In a regular network (without a VPN), your device learns the route to a website through the routing table stored in the operating system. Each routing table entry specifies: for which IP address or network packets should be sent through a particular gateway (e.g., your router) and which interface to use (Wi-Fi, Ethernet, mobile data).
When you connect to a VPN, the operating system adds new routes. By default, most VPN clients add a “default route” that directs all internet traffic into the VPN tunnel. Without this rule, packets to websites would go directly to the ISP, making the VPN useless.
2. What Happens to Routing When a VPN Connects
After establishing a VPN connection, the client creates a virtual network adapter (e.g., TUN or TAP). It is assigned an internal IP address from the VPN server’s range. The client then modifies the system routing table:
- A default route (0.0.0.0/0) is added through the virtual adapter, with a metric higher than the normal route. Now all packets go to the virtual interface, which encrypts them and sends them to the VPN server.
- If needed, exceptions are added — routes for the local network (to keep access to a printer or local NAS) or for specific IPs that should not go through the VPN.
- A route to the VPN server itself is added through the regular interface (otherwise the connection could not be established).
In decentralized VPNs like KelVPN, routing can be more flexible: the client may choose a chain of nodes and dynamically update routes when switching nodes.
3. Full-tunnel vs Split Tunneling
There are two main traffic routing modes in VPNs.
| Mode | Description | Advantages | Disadvantages |
|---|---|---|---|
| Full-tunnel | All device traffic goes through the VPN. | Maximum privacy, hides all activity from the ISP. | Speed may be lower, possible issues with local services. |
| Split tunneling | Only part of the traffic (e.g., browser) goes through the VPN; the rest goes directly. | Higher speed for local content, saves bandwidth, simultaneous access to local resources. | Risk of leaks if exceptions are misconfigured. |
Full-tunnel mode is simpler and safer for most users. Split tunneling is useful when you need some applications (e.g., a game client) to keep high speed while your browser uses the VPN to bypass blocks. KelVPN supports split tunneling with the ability to specify which apps or IP addresses go through the VPN and which go directly.
4. How Routing Affects Speed and Security
Improperly configured routing can lead to data leaks (e.g., DNS queries going directly to the ISP) or speed drops due to suboptimal paths. Here are the key aspects:
- Routing leaks: If the default route is not added or has a lower priority, some traffic may go outside the tunnel. Regularly check for IP and DNS leaks.
- Path optimality: Even with correct routing, packets may go through congested nodes. A good VPN client allows you to select a server with better routing.
- Route metrics: Operating systems use metrics to choose an interface. The VPN client must set a lower metric for the virtual adapter; otherwise traffic may bypass the VPN.
In KelVPN, routing is automatically configured on connection, and the built-in Kill Switch ensures that if the tunnel drops, internet access is completely blocked, preventing leaks.
5. Dynamic Routing in Decentralized VPNs
In traditional VPNs, the client connects to a fixed server. In decentralized networks (like KelVPN), routing can be dynamic: the client receives a list of available nodes, their load, ping, and builds a route in real time. If the current node becomes overloaded, the client automatically switches to another with minimal impact on the connection. This improves fault tolerance and ping stability (reduces jitter).
Such dynamic routing also helps bypass blocks: if a node’s IP is blacklisted, the client simply chooses another node.
6. How to Check Current Routing and Fix Problems
Users can view their system’s routing table.
- Windows:
route printin Command Prompt. Look for the0.0.0.0entry — it indicates the default route. The active default route should point to the VPN virtual adapter. - Linux/macOS:
netstat -rnorip route. Also look for the default gateway. - Android/iOS: direct access to the routing table is not available, but you can check your IP through any website — it should be the VPN server’s IP.
If you suspect a leak (traffic not going through the VPN):
- Check your IP at ipleak.net — if it shows your ISP’s IP instead of the VPN’s, routing is incorrect.
- Reconnect to the VPN.
- Enable Kill Switch (in KelVPN it is always on).
- Manually delete old routes (requires admin rights) — better to contact VPN support.
7. Routing in KelVPN: Flexibility and Security
KelVPN offers several advanced routing features:
- Automatic node selection: The client measures ping to available nodes and chooses the best one for speed and stability.
- Split tunneling: You can specify which applications go through the VPN and which go directly. Convenient for gaming and local services.
- Always-on Kill Switch: When the tunnel drops, internet is completely blocked, eliminating any leaks.
- IPv6 support: KelVPN properly handles IPv6 traffic, routing it into the tunnel or blocking it as needed.
Thanks to the decentralized network, routing in KelVPN does not depend on a single provider and is resilient to individual node failures.
8. Frequently Asked Questions About VPN Routing
Glossary
- Routing: The process of determining the path for packets in a network.
- Routing table: A set of rules in the OS that determines which interface and gateway to use for each destination.
- Default route: The rule for all destinations not explicitly listed (0.0.0.0/0).
- Full-tunnel: Mode where all traffic goes through the VPN.
- Split tunneling: Mode where part of the traffic goes through the VPN and part goes directly.
- Route leak: Unintentional sending of traffic outside the VPN tunnel due to routing errors.
- Route metric: A numerical parameter that determines route priority.
- Policy-based routing: Routing based on rules (by IP, port, application).
Conclusion: Manage Routing for Maximum Effectiveness
Routing is the “conductor” of your internet traffic. Understanding how a VPN changes routing tables helps you diagnose leak problems, configure split tunneling, and improve speed. Modern solutions like KelVPN automatically optimize routes, but knowing the basics allows you to solve non-standard situations yourself. Use full-tunnel mode for maximum privacy and split tunneling to balance speed and security.
