4
Packet Loss Measurement using the Ping Command
This procedure checks the functionality of the AFBR-
0545Z media converter board and creates an optical link
network to measure packet loss.
1. Connect the power supply to the AFBR-0545Z media
converter boards. LED1 and LED2 will ash one time
and a red light can be seen coming out of the AFBR-
5972Z module. This indicates that the media converter
boards are functional.
2. Connect one end of CAT 5 patch cable to the RJ45
interface and other end to the network. LED1 will ash
on and o . Connect the RJ45 interface of the other
media converter board to a computer or a laptop. LED1
will ash on and o .
3. Connect the 2-meter POF duplex cable between the
two AFBR-5972Z media converter boards. This makes a
duplex communication optical link. LED1 and LED2 on
both media converter boards will ash synchronously,
indicating an active optical link network has been
created.
With the link established, a packet loss measurement
can be made with the Internet Ping protocol and ping
command.
Internet Ping Command
The Internet ping command bounces a small packet
o a domain or IP address to test network communica-
tions, and then reports how long the packet took to make
the round trip. The ping command is one of the most
commonly used utilities on the Internet by both people
and automated programs for conducting the most basic
network test.
Figure 5. Ping statistics for avagotech.com: Packet loss = 0%
Command Prompt in Windows NT, 2000, and XP
To use the ping command, open a Command Prompt
window:
Click Start Click Run Type cmd and press enter
In Command Prompt window type “ping -n 10 avagotech.
com”. This means that the ping command will ping
avagotech.com ten times (Figure 5).
As shown in Figure 5, the ping command pinged the
avagotech website ten times and also provided statistics
for the avagotech.com link. For example, the number of
packets sent, received and lost as well as the minimum,
maximum and average round-trip time in milliseconds
were reported. In this example there were no packets lost
(0% loss).
For the test shown in Figure 6, the CAT5 patch cable
from the media converter board (which is connected to
a computer or laptop) was purposely removed to observe
the packet loss. The results of the ping command “ping -n
10 avagotech.com” – with the CAT5 patch cable removed
– show the packet loss phenomena. Ten packets were
sent, six packets were received and four packets failed to
reach the destination host. Packet loss was 40%.
