Hi Folks,
I have run into an issue on our Metro-Ethernet SP network which is described as follows:
Device - ME3400
1. Inbound policer on fa0/1 (connected to customer equipment) set at 9.5 Mb/s - Tc 250 ms (UNI port)
2. Outbound shaper applied on Gig0/1 interface at 45Mb/s. (NNI port) This connects via a pair of Microwave radios (45Mb/s) to a ME3600 PE device.
3. When frames leave the Gig0/1 interface (NNI port) we experience a huge drop rate due to bursts overflowing the buffer when we transmit at 9.5Mb/s and use a Tc of 250ms. Y.1564 test used with explicit configured burst size.
4. I have maxxed out the buffer size and this doesnt help much at all.
I have raised a TAC case and asked them if they could confirm that the egress interface buffers were too small for these bursts. They have confirmed this and now I am stuck with finding a device that will buffer enough packets to use a 45Mb/s egress shaper effectively while handling the burst size of the 9.5Mb/s ingress interface.
What devices are out there that shape/buffer better than the ME3400 but can be used in a Metro-E network? BTW, this also occurs on the ME3600 platform. Is there an additional box that is effective? Im thinking I need to feed the traffic out of the ME3400 unshaped into a {insert magic box name here} and then egress shape on the magic box with better buffers?
Any advise would be appreciated.
Cheers,
Rob