What does troubleshooting, baselining, capacity planning and implementation have in common?
Every one of those tasks involves some sort of bandwidth or throughput validation. Figuring out your true throughput transcends all network disciplines and becomes a common ground in all my engagements.
We have all been asked at some point in our careers to prove that your carrier has delivered what they promised. Or maybe that age old question, “How much bandwidth can we get out of your internal network", to justify an equipment upgrade.
Traditionally, analysts have used simple ftp or other file transfer applications to ‘load up’ or measure throughput. But as network latency surpassed disk drive delay, these results would be called into question. Simply put, the network is faster than the disk drive. That is when applications like iperf, Chariot, Qcheck and traffic bit generators came into the picture since they can be configured to not access the disk.
As the industry struggled with some sort of standard for network testing, common important points were identified. Things such as varying frame sizes, rates or utilization became common dials that we turned while testing throughput.
When RFC2544 was created in 1999 as a methodology to benchmark network devices such as switches and routers, we finally had a common methodology to provide accurate and comparable values for comparison when benchmarking. For those of you not familiar with RFC2544, it basically describes 6 subsets. In many cases, I have seen test equipment measure Latency, Loss and Throughput which has more than adequately helped us all out.
Since then, service providers shifted from only providing pipes to enabling various services through links such as Voice, Video as well as good old data. Unfortunately RFC2544 testing can take several hours to complete which is an issue when troubleshooting in the field. Lastly, certain applications (IPTV) and protocols required additional measurements such as jitter.
The ITU Y.156sam defines three key test rates based on the MEF service attributes for Ethernet virtual circuit (EVC) and user-to-network interface (UNI) bandwidth profiles.
When Fluke Networks announced that the latest software upgrade to their Optiview XG is compliant with ITU (International Telecommunications Union) ITU‐T Y.1564 standard for performance testing, I was very curious. The Performance testing can measure end‐to‐end network performance in terms of bandwidth, latency, jitter, loss and availability up to 10 Gbps. With Class‐of‐Service testing and multiple test streams (up to 8 simultaneous) you can ensure availability and performance of QoS throughout your network, and whether carrier links are supporting QoS.
As an added bonus, Fluke has allowed reflector support which means you can use other Fluke networks equipment other than an XG for this testing.
In this video I use an XG and a LinkRunner AT to setup and perform a test.