Culmen RADIUS & Quota Engine

Standalone authentication and fair-use enforcement for MikroTik networks. Deploy alongside your existing billing system.

What it does

• PPPoE authentication via RADIUS, with per-plan rate limits
• Daily fair-use quota with automatic throttle on breach
• Monthly quota layer on top of the daily meter
• Cache-exempt metering — traffic served from local caches runs at unlimited speed and is credited back, daily and monthly. Services you choose to count, such as paid streaming, run at full speed and still count
• Free windows — unmetered hours with their own speed ladder, applied and reverted on schedule
• Separate metering windows per plan type — a 24-hour window anchored at midnight for some plans, a partial-day window for others
• MAC binding, trust-on-first-use, resettable from the panel
• Subscription expiry, simultaneous-use limits and stale-session cleanup — expiry compared in the RADIUS server's own timezone, enforced on the expiry day itself, and disconnected on whichever router holds the session
• New accounts metered from their first minute — no free first day for anyone activated after the daily baseline
• Reject logging — failed authentications are recorded with a reason, and pruned on a schedule

The bit most implementations get wrong

Rate limits only apply at authentication time. Change a subscriber's rate in RADIUS without disconnecting them and nothing happens until they next redial — so the customer you just upgraded is still on the old speed, and the customer you just released from a throttle is still throttled. This engine issues a CoA disconnect in both directions, on throttle and on release, with tracked retries.

Why the meter is not RADIUS accounting

RADIUS interim updates arrive in five-minute lumps. At 380 Mbps one lump is about 14 GB landing at once — enough to throttle and disconnect a customer on a peak that has gone a minute later. The engine meters from the router's own queue counters every minute, carries the count across redials, and falls back to accounting only when the meter is stale. Usage climbs smoothly, and a throttle only ever lands on real use.