Per-interface 4G monitor: live view of how much your mobile carrier will charge

If you use PingArmor with USB tethering as backup, have you ever wondered exactly how much each interface consumed in this session? The carrier bills the chip’s plan for every byte transmitted — so knowing what went out through 4G is the difference between consciously managing the data cap and being surprised on the bill.

Without visibility during the session, it’s impossible to notice a bandwidth leak while it’s happening. That’s why PingArmor now shows bytes per interface live — on the dashboard while you’re playing, and on the final report when you disconnect.

On the dashboard: bytes in real time

Below each interface in the “NETWORK INTERFACES” card, two new lines appeared: arrows up (TX, sent) and down (RX, received). The number updates every 2 seconds.

The example shows exactly the bug scenario from the start: tunnel running on Ethernet, and 4G secondary (Android USB tethering) consuming data even on “standby”. Even if it’s only 22 KB of upload, the carrier starts billing on any byte transmitted.

The yellow “4G” badge marks interfaces flagged as mobile data (more on this below). It’s a visual warning: anything that shows up on that line is coming out of your 4G/5G plan.

How it works

The reading uses a native Windows API called GetIfEntry2 — the same one Task Manager queries to show network consumption. PingArmor reads the counter once when you click “Connect” (session baseline) and then every 2 seconds. The delta between the two readings is what appears on screen.

No extra privileges: GetIfEntry2 has worked in user mode since Vista. Nothing needs to be authorized by Windows — it’s just reading a counter the adapter driver already keeps.

No external network polling: zero packets leave your PC to collect this info. It’s not a speedtest, not a traceroute, nothing that generates traffic. It’s just reading a number the network driver already maintains.

In setup: mark the interface as “limited data plan”

On the configuration screen, each interface now has a new checkbox: “This interface has a mobile data cap”.

The checkbox controls the 4G badge on the dashboard. Checked = it appears and reminds you that data there costs money. Unchecked = it disappears, even if PingArmor auto-detected the interface as cellular.

You’re in charge of the override. If your home Wi-Fi is metered (some rural plans still are), tick the checkbox manually. If your USB tethering is just for testing and has no cap, untick it and the badge stops bothering you.

USB tethering auto-detection

When you plug your Android phone into the PC and enable “USB tethering”, Windows creates an interface called “Realtek RTL USB Remote NDIS” or “Samsung Mobile USB Modem” (name varies). To Windows, it’s just another Ethernet adapter — same type as the regular network cable.

PingArmor looks at the adapter description and, if it finds words like “RNDIS”, “Mobile”, “USB” or “Wireless WAN”, marks it as cellular automatically. This pre-judgment shows up as a checked-checkbox suggestion in setup — but, as we said, you decide.

For real Wi-Fi, classification is straight: IF_TYPE_IEEE80211 (71 in Win32 convention). Cable: IF_TYPE_ETHERNET_CSMACD (6). Newer 5G with native modem: IF_TYPE_WWANPP (244) + keyword “5G”/“NR” in description.

On the final report: shareable as text

When you disconnect, the Session Report opens automatically (if there was at least one failover) or can be opened via “View report” on the stats card. It now includes a “PHYSICAL INTERFACES” section with the session total.

Clicking Share, the text goes to the clipboard formatted like:

PingArmor — Session Report
Duration: 00h32 | 0 saves
Data: 26.1 KB TX / 0 B RX
Ping: 0ms (avg) / 4ms (peak)

Physical interfaces:
Ethernet ↑ 5.2 MB ↓ 84.7 MB
Ethernet 3 ↑ 39.7 KB ↓ 43.8 KB [4G]

Paste it straight into WhatsApp, Discord, or the clan chat. Whoever helps you with diagnostics (or whoever you want to impress with your save count) gets everything formatted.

Where to look (and why)

PingArmor is designed to minimize secondary usage as much as possible. When everything’s fine, all traffic goes through the primary — the secondary only kicks in during real failover (primary going down). In normal use, a few KB will always show up there (link probe + monitoring keepalive). That’s small and expected.

High volume on the secondary without an active failover is the warning sign. If you notice it, two leads to investigate:

1. Process order

The correct order to open things is:

1. Open PingArmor
2. Connect the tunnel (status goes to “Protected”)
3. Open the game

Reversing it (game before tunnel) doesn’t directly cause extra consumption on the secondary, but it leaves the game vulnerable: the TCP socket binds to the physical IP instead of the tunnel; if failover hits, the game connection drops and reconnects. Each reconnect generates a bit more traffic and, depending on the server, can log you off your character. Easy fix: close the game and reopen with the tunnel already connected.

2. Tibia Global legacy behavior (already adjusted)

Earlier versions of the app left wide routes (0.0.0.0/1 + 128.0.0.0/1) active on the tunnel even after you closed the Tibia client, and any failover from that point on funneled the entire web traffic (browser, Discord, Windows updates) through 4G. The behavior affected only Tibia Global; RubinOT never had that path active.

Already adjusted: the wide routes are now automatically removed 30 seconds after the Tibia client closes. If you reopen Tibia, they come back in up to 2 seconds. You don’t have to do anything — update to the new version and the new behavior is already active.

3. Phone still plugged in after closing PingArmor

This is the most common “phantom” 4G usage scenario. While PingArmor is running, it controls interface metrics (primary with priority, secondary only for failover). But the moment you close the app, Windows reverts to treating both interfaces normally, with equal or similar metrics. If the phone stays plugged in via USB, any background app — Discord, Windows Update, Steam/Origin game updates, a browser left open — can pick the 4G route without you noticing.

Recommended routine when you’re done playing:

1. Close PingArmor (or at least disconnect the tunnel)
2. Unplug the phone from USB (or disable tethering on the phone)

That’s the only way to guarantee the system has no option left to fall back on 4G while you’re not looking.

Privacy

All of this counting is 100% local. The bytes read by GetIfEntry2 stay inside the app — no PingArmor server is notified. No server-side telemetry was added. If you go offline after playing, the history doesn’t leak anywhere.

The only thing that leaves your PC is what you manually copy to the clipboard and paste wherever you want.

See it before it becomes a bill

With the live view, you can notice within one hour if the secondary interface is transmitting unusually high data even with the main game using Ethernet. Just disconnect, check the cause, and avoid the charge at month’s end.

If you use PingArmor in passive mode with USB tethering, open the app and watch the numbers while you play. It’ll feel like paranoia until the day it matters.

Update

Auto-update grabs the new version automatically. If it hasn’t yet, go to /en/download and grab it manually. The feature works on any Windows 10/11 — no extra requirements.

Got a question? Check the FAQ or get in touch at [email protected]. And if you’re the kind of person who likes knowing why decisions get made, take a look at how the app protects your game during failover — that’s the other half of the story.