It is the preferred option. It requires no specific configuration. Just make sure that in Configuration->RADIUS, Mikrotik-Rate-Limit is enabled (this is the default).

Optionally, a percentage can be specified to scale the policy limits. One can keep limits in the BQN below those of the PPPoE servers. The goal is to enforce the plans in the BQN and have the PPPoE servers as backup and to limit local traffic that does not go through the BQN (for example, direct traffic between subscribers in the same access area).  The scaling percentage is defined in the field Rate-Limit Scaling % in Configuration->Radius (by default,100%, i.e., no scaling).

For example, with a percentage of 80%, a 125 Mbps limit in RADIUS will be converted to a 100Mbps limit in the BQN (125*0.8).

The percentage is applied to all speed parameters of the policy (limit, burst speed and burst threshold).

And that’s all. You can now check policies and subscribers.

Mikrotik-Rate-Limit Field Format

For information purposes, the AVP field Mikrotik-Rate-Limit is described. The Mikrotik RADIUS client will automatically codify this field according to its configuration. The format is as follows:

rx-rate[/tx-rate] [rx-burst-rate[/tx-burst-rate][rx-burst-threshold[/tx-burst-threshold] [rx-burst-time[/tx-burst-time][priority] [rx-rate-min[/tx-rate-min]]]]

where:

• rx-rate: rate limit in uplink.
• tx-rate: rate limit in downlink.
• rx-burst-rate: burst rate in uplink.
• tx-burst-rate: burst rate in downlink.
• rx-burst-threshold: burst threshold in uplink(average speed not to be exceeded before granting a new burst).
• tx-burst-threshold: burst threshold in downlink(average speed not to be exceeded before granting a new burst).
• rx-burst-time: uplink burst duration, in seconds.
• tx-burst-time downlink burst duration, in seconds.
• priority: ignored.
• rx-rate-min: ignored.
• tx-rate-min: ignored.

Speed can be given in Mbps (M) or Kbps (K). For example, a policy with a downlink limit of de 20Mbps, an uplink limit of 15Mbps, burst of double the limit, thresholds equal to the limit and a burst duration of 5 seconds, would be:

15M/20M 30M/40M15M/20M 5/5

If no burst is required, the values are set to zero:

15M/20M 0K/0K 0K/0K0/0

And if the limits are symmetrical, it is enough to specify one of them (the other will take the same value). For example, a symmetrical 15Mbps (in both downlink and uplink).

15M 0K 0K 0

The BQN creates dynamically a policy, if it does not exist yet, using the parameters in this field. A policy name in the BQN cannot have spaces, so spaces are replaced by an underscore (“_”). For example, the policy from RADIUS “20M/40M 0K/0K 0K/0K 0/0” will be converted to “20M/40M_0K/0K_0K/0K_0/0”in the BQN. The policy name is limited to 31 characters (if the limits is exceeded, the name will be truncated). For example, “20000K/40000K40000K/80000K 20000K/40000K 5/5” will lead to a BQN policy named “20000K/40000K_40000K/80000K_200”.

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