test introduction
Damage network analyzer is used to simulated network link for product damage, can be used for IPTV, multimedia services testing and test router switches. It has typical damage simulation functions such as bandwidth limitation, delay/jitter, packet loss, disorder, repeated messages, queue depth, physical link, etc., and can set up multiple scenarios at the same time , and each damage application scenario can be independently configured. Damage to test the adaptability of the network transmission data service to the corresponding link damage.
The simulated WAN environment can easily simulate the network bandwidth, delay, data loss, congestion and other network damage states, and realize the performance of applications or network equipment under various network conditions under laboratory conditions. test.
This article uses the offset + data value mode to filter the traffic with vlan as an example to introduce the use of the advanced filter mode of the damage meter.
Test topology
Topology description
ØThe two ports of the tester are connected to the two ports of the damage tester
Ø test port P1 emitted flow meter after injury, sent from the B port into the port P2.
Test ideas
1. Send a traffic with Vlan on the tester
2. Create an advanced filter on the damage meter, filter the source IP, and set a 1ms delay
3. After the damage is applied to the damage meter, it can be found in the tester statistics that the maximum flow delay is 1ms
Test steps
Create Vlan traffic on the test
Send traffic, you can see a maximum delay of 2 .688 US.
Damage meter selects advanced filtering mode
Fill in the calculation rules according to the situation. Regular expressions are used here. For example, only rule a is used in this example, so just fill in a here.
Intermediate offset calculation
The offset is calculated from the beginning of the message
MAC header 14 bytes:
Vlan first 4 bytes
The IP header has 12 bytes before the source IP
The IP header has 16 bytes before the destination IP
For example, in the message, the source IP address is 192.168.0.2 (0xCAA80002), and the destination IP is 192.168.0.10 (0xCAA8000A)
Therefore, it is necessary to filter the source IP, fill in the offset 14+4+12=30, (if it is the destination IP offset is 1 4 + 4 + 16 = 34 ), fill in the data C0A800020000 (because 6 bytes are supported here Data, all the last 2 bytes are 0), and the mask is filled with FFFFFFFF0000 (only the first 4 bytes are masked).
1. Set the delay damage, 1ms. And start the damage
Damage result
Check the delay statistics on the tester, you can see that the maximum delay is 1ms
