Network bandwidth metering script

[sire]

Hi all,

I have written a Perl script that (very) roughly meters network bandwidth to a host selected on a network map. The script can be added to Zabbix through Administration->Scripts menu.
Metering is done by sending ICMP pings of different size and calculating network bandwidth based on round-trip time (RTT) and packet size according to the formula:
Bandwidth = Packet size / (RTT/1000/2).
Metered bandwidth greatly depends on the packet size. The highest speed is achieved at the largest packet size (65535 bytes including ICMP and IP headers). One more thing to note is that metered bandwidth is the average of upload and download bandwidths.

Comments are welcome.

[dima_dm]

I think, is useful to add also bandwidth speed in bps.

[sire]

I think, is useful to add also bandwidth speed in bps.

Do you mean that the script should automatically scale the numbers and add a correct suffix: K, M if necessary?

[dima_dm]

Do you mean that the script should automatically scale the numbers and add a correct suffix: K, M if necessary?

No. bps (bit per second) and Bps (Byte per second).
Than more devices along the trace of packets (switch, router, firewall etc), so much the worse an estimation of a bandwidth.
Example:

I tested this script on 100Mbps link 
1 hop, 1 device 
IP packet size 84 B:    RTT = 0.157 ms, speed = 696.7 KBps
IP packet size 150 B:   RTT = 0.180 ms, speed = 1323.8 KBps
IP packet size 1500 B:  RTT = 0.675 ms, speed = 4259.3 KBps
IP packet size 10000 B: RTT = 2.117 ms, speed = 9200.1 KBps
IP packet size 64000 B: RTT = 11.272 ms, speed = 11084.6 KBps

Speed (min/avg/max) = 696.7/5312.9/11084.6 KBps
11084.6 KBps= 88676,8 Kbps= 88,7 Mbps

6 hop, 9 devices
IP packet size 84 B:    RTT = 1.457 ms, speed = 75.1 KBps
IP packet size 150 B:   RTT = 1.450 ms, speed = 164.3 KBps
IP packet size 1500 B:  RTT = 4.517 ms, speed = 636.5 KBps
IP packet size 10000 B: RTT = 9.811 ms, speed = 1985.2 KBps
IP packet size 64000 B: RTT = 40.066 ms, speed = 3118.5 KBps

Speed (min/avg/max) = 75.1/1195.9/3118.5 KBps
3118.5 KBps=24948 Kbps=24,9 Mbps

[sire]

No. bps (bit per second) and Bps (Byte per second).
Than more devices along the trace of packets (switch, router, firewall etc), so much the worse an estimation of a bandwidth.

I'll add a -b option to show Kbps. And thanks for the report.

[sire]

Here is a new version with the promised -b option.