RFC2544 test

[mmurphy]

Good Afternoon,

I want to rule out the Netonix as a possible source of an issue we have.

we have a client running a RFC-2544 test across a link.
it is set up like the following

Client site A (Ciena router)-->Juniper EX2300c switch-->Microwave licence Radio link-->Netonix--> Juniper ACX2100-->Layer 2 Fiber Circuit --> Data Center Juniper ACX-2100-> Client Site B

They are experiencing drops when trying to push 320 Mb at 68 byte size. Netonix interfaces are set to 9600 MTU.

i don't believe the Netonix is the cause but maybe you could advise.
If you need more info, please let me know. i can send on RFC test results if required.

Thanks in advance.

[mike99]

Why not just do the test only on the netonix to check if it's the source of the problem ?

You have at less 8 devices in the path. Personally, I would pass the test through each single device first and then, begin to add those one by one on the daisy chain with a new test every time you add a device.

[mmurphy]

Apologies for not updating, it took some time to diagnose due to the amount of different parties.
we bypassed the switch, but issue still remained. turns out our customer had their customer running tests also.
This reply from one of our radio vendors helped explain what was going on, it doesn't look like switch is at fault but how the testing was carried out by our clients.

Radio vendor -
"When you insert another device into the path, especially routers (but also switches, through which further traffic passes), the inter-packet gaps change. This gap is sometimes very long (corresponds to traffic e.g. 50 Mbps) and sometimes zero (minimum possible, which corresponds to a speed of 1Gbps). At zero gap, so-called bursts are formed.

If a burst comes into link, packets that fit in the buffer are transmitted at 350 Mbps, the others are dropped (In discards).
If you turn on flow control, the buffer in the switch will also be used to store packets (total buffer size is radio buffer + switch buffer). In this case, the packets are dropped by the switch (HS-SW1).

I hope this explanation has helped you understand what's going on in the network.

There are several ways to solve bottle neck: Flow control, traffic shaping, QoS and even the TCP connection itself solve it.”