Bandwidth management - setting the speed of the link

Typically, problems with bandwidth management are caused by the Internet link speed being set incorrectly.

To provide the necessary bandwidth for mission-critical applications, Kerio Control enables you to reserve bandwidth for those applications and then automatically limits lower priority traffic to the remaining available bandwidth.

However, the bandwidth management feature decreases the link's capacity somewhat. For that reason, Kerio Control needs to know the real bandwidth of the link.

Real link bandwidth

The real bandwidth is the maximum speed of the link's data transmission. Because control information is transmitted in addition to data, the real bandwidth is around 20 percent lower than the speed stated by the ISPInternet Service Provider - the organization which can provide Internet service..

Technology Speed stated by ISP Real speed
SDSL 2 Mbit/s 1592 Kbit/s
ADSL Download: 8 Mbit/s, Upload: 512 Kbit/s Download: 6250 Kbit/s, Upload: 400 Kbit/s
Optical fiber 20 Mbit/s 15.8 Mbit/s
Ethernet 100 Mbit/s 79 Mbit/s

How to find out the link's speed

To find out the speed of your link, use an open tool, such as