Re: Long-haul 100Mbps EPL circuit throughput issue

On 5 Nov 2015 21:50, "Eric Dugas" wrote: > > Hello NANOG, > > We've been dealing with an interesting throughput issue with one of our > carrier. Specs and topology: > > 100Mbps EPL, fiber from a national carrier. We do MPLS to the CPE providing > a VRF circuit to our

Re: Long-haul 100Mbps EPL circuit throughput issue

hi eric On 11/05/15 at 04:48pm, Eric Dugas wrote: ... > Linux test machine in customer's VRF <-> SRX100 <-> Carrier CPE (Cisco > 2960G) <-> Carrier's MPLS network <-> NNI - MX80 <-> Our MPLS network <-> > Terminating edge - MX80 <-> Distribution switch - EX3300 <-> Linux test > machine in

Re: Long-haul 100Mbps EPL circuit throughput issue

Eric, I have seen that happen. 1st double check that the gear is truly full duplexseems like it may claim it is and you just discovered it is not. That's always been an issue with manufactures claiming they are full duplex and on short distances it's not so noticeable. Try to perf in both

Long-haul 100Mbps EPL circuit throughput issue

Hello NANOG, We've been dealing with an interesting throughput issue with one of our carrier. Specs and topology: 100Mbps EPL, fiber from a national carrier. We do MPLS to the CPE providing a VRF circuit to our customer back to our data center through our MPLS network. Circuit has 75 ms of

Re: Long-haul 100Mbps EPL circuit throughput issue

> > > Modern TCPs support and typically use window scaling (RFC 1323). You > may not notice it in packet dumps because the window scaling option is > negotiated once for the connection, not repeated in every packet. > > Absolutely. Most host OS should support this by now. Some test utilities

Re: Long-haul 100Mbps EPL circuit throughput issue

On Thu, Nov 5, 2015 at 9:17 PM, Pablo Lucena wrote: > With default window size of 64KB, and a delay of 75 msec, you should only > get around 7Mbps of throughput with TCP. Hi Pablo, Modern TCPs support and typically use window scaling (RFC 1323). You may not notice it

Re: Long-haul 100Mbps EPL circuit throughput issue

> On Nov 5, 2015, at 8:18 PM, Pablo Lucena wrote: > > ​I realized I made a typo: switch.ch has a nice bandwidth delay product calculator. https://www.switch.ch/network/tools/tcp_throughput/ Punching in the link

Re: Long-haul 100Mbps EPL circuit throughput issue

> With default window size of 64KB, and a delay of 75 msec, you should only > get around 7Mbps of throughput with TCP. > > You would need a window size of about 1MB in order to fill up the 100 Mbps > link. > > 1/0.75 = 13.333 (how many RTTs in a second) > 13.333 * 65535 * 8 = 6,990,225.24 (about

Re: Long-haul 100Mbps EPL circuit throughput issue

Along with recv window/buffer which is needed for your particular bandwidth/delay product, it appears you're also seeing TCP moving from slow-start to a congestion avoidance mechanism (Reno, Tahoe, CUBIC etc). Greg Foletta g...@foletta.org On 6 November 2015 at 10:19, alvin nanog

Re: Long-haul 100Mbps EPL circuit throughput issue

With default window size of 64KB, and a delay of 75 msec, you should only get around 7Mbps of throughput with TCP. You would need a window size of about 1MB in order to fill up the 100 Mbps link. 1/0.75 = 13.333 (how many RTTs in a second) 13.333 * 65535 * 8 = 6,990,225.24 (about 7Mbps) You