Without doubt, there can be few tools that parallel the usefulness and diagnostic ability of traceroute and ping. These tools offer invaluable insight into the operation and performance of network elements that we take for granted in today’s use of the Internet. Whether it’s a case of trying to discover why your laptop wifi or home broadband is not working, or why the office laser printer is not working, tech-savvy users and network engineers alike have long been acquainted with the use of these tools in order to pinpoint problems.

The same goes for network trouble-shooting in large-scale ISP networks. The principles are the same, even if the interface bandwidths are slightly different. Recently, though, I was offered a stark reminder of just how dependent today’s large-scale ISP networks are on link aggregation technology, and how a technology that makes simple promises can be complicated underneath. Continue reading…