# Choosing a BNG: chassis, MikroTik or software

The broadband network gateway is where every subscriber session lives, so the platform an ISP chooses sets its cost, its scale ceiling and how it operates. There are three realistic choices, and they suit different operators.

27 September 2026

[ISP & Network Operators](https://netavo.com/insights)

## What a BNG does, and why the choice matters

A BNG terminates subscriber sessions, PPPoE, IPoE or L2TP, authenticates each one against RADIUS, assigns addresses, enforces the subscriber's speed, applies carrier NAT and accounts for usage. It is the busiest and most load-bearing box an ISP runs. The platform you build it on decides your capital cost, how you scale, how long you wait for capacity, and how much of the system you control.

## Three ways to build a BNG

| Platform | Strengths | Trade-offs |
| --- | --- | --- |
| Chassis router | Very high port density and capacity, deep-buffer line cards, mature feature set | High capital cost and per-subscriber licensing, long lead times, vendor lock-in |
| MikroTik | Low cost, quick to start, familiar to many small operators | CPU-bound termination, scales by adding boxes, limited deterministic CGNAT logging |
| Software BNG on x86 | Commodity servers, scales on cores and NICs, integrated CGNAT, operational flexibility | You size and operate the hardware; raw port density is lower than a chassis |

## Matching the platform to the operator

A chassis earns its place where raw port density and deep buffering are the deciding factors, and the budget and lead times are acceptable. MikroTik is a reasonable start for a small network, until session counts, CGNAT scale or deterministic logging begin to strain it. A software BNG on standard x86 suits an operator that wants to scale on commodity hardware, keep integrated CGNAT, and avoid per-subscriber licensing, accepting that it sizes and runs the servers itself.

Netavo BNG is a software BNG for x86: it terminates PPPoE, IPoE and L2TP, includes carrier-grade NAT, and scales to large subscriber counts on standard servers. If you are weighing a move from an existing platform, the Netavo BNG site has detailed guides on [replacing a chassis BNG](https://netavobng.com/engineering/chassis-bng-to-software) and [outgrowing a MikroTik edge](https://netavobng.com/engineering/mikrotik-to-netavo), and a full [engineering library](https://netavobng.com/engineering) on the data-plane and protocol detail.

## Common questions

### What access protocols does Netavo BNG terminate?

Netavo BNG terminates PPPoE, IPoE and L2TP sessions, authenticating each subscriber against RADIUS and assigning IPv4 and IPv6 addressing.

### Does a software BNG include CGNAT?

Netavo BNG includes integrated carrier-grade NAT with deterministic port blocks, so NAT is part of the same platform rather than a separate appliance.

### Do I have to replace everything at once?

No. A BNG migration can be staged, running the existing and new platforms side by side and moving subscribers in groups. The Netavo BNG migration guides cover this in detail.

## Related services

### [ISP BNG & CGNAT Systems](https://netavo.com/services/bng)

Netavo BNG, a carrier-grade x86-based BNG and CGNAT platform for internet service providers.

### [ISP Network Services](https://netavo.com/services/isp)

IP transit, backhaul and L2TP broadband for internet service providers and network operators.

## Weighing up a BNG platform?

Tell us about your access model and subscriber numbers, and an engineer will talk through whether a software BNG fits and how a migration would be staged.

[Work with us](https://netavo.com/work-with-us)

Source: https://netavo.com/insights/choosing-a-bng