### What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

View all Tags

# How much bandwidth is required for remote probe and core server connections?

#### 0

What's the transfer volume of a remote probe and core connection and how does it affect bandwidth utilization?

Created on Feb 17, 2010 4:15:05 PM by

Last change on Feb 17, 2010 4:26:12 PM by

#### 2

The bandwidth used for the core and probe connections depends on the number of sensors being monitored, the number of channels defined for the same, as well as the scanning interval.

100 SNMP sensors, each with 2 channels (in & out) generate roughly 1 kbit/s plus 20 bytes/minute (due to the core "keep alive" message). This reflects a daily load of about 11 Mbyte/day.

A breakdown of the bandwidth required for remote probes and the core server is provided below:

## Premise: sensors monitored

• 24 ports * 2 channels (in & out) = 48 values
• 15 server sensors * about 4 channels (depending on kind) = 60 values
• 2 firewall counter * 2 channels = 4 values

## Calculation

Let us assume an interval of 1 minute for all sensors and generously round up.

We have to send about 50 messages with 150 values from the probe to the core.

A value uses 28 bytes. A message uses 22 bytes plus the values (if there is no message text).

50 messages * 22 bytes + 150 values * 28 bytes = 5300 bytes / minute = 706 bits/s = below 1kbit/s. Or about 7 Mbyte/day for the probe -> core messages.

The core sends a "keep alive" message to the probe every 60s. That is 20 bytes / Minute.

When the probe connects or anything is changed in the configuration the required information is sent to the probe once. This does not create a constant load.

Increasing the interval from 1 minute to 5 minutes creates 1/5 of the load.

Note: These numbers apply to common monitoring load. For specific monitoring tasks they might differ. Syslog Receiver and SNMP Trap Receiver sensors, for example, generate extra load on the connection when data is requested from the core (like message lists or reports).

Created on Feb 17, 2010 4:20:14 PM by

Last change on Aug 3, 2015 4:16:35 PM by

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.