Why deploy MDM tools?

The wide variety of potential data transfer issues makes network performance problems difficult to solve. This is particularly true of cases related to packet loss within the backbone, or cases where data transfer is prevented by backbone problems. The biggest challenge in both cases is to identify the location of the problem.

More than 95% of the incidents reported to the Network Operating Centres (NOCs) are caused by hardware or circuit (fibres, etc.) failures within their local domain. The remaining incidents are related to performances or multi-domain issues. While information related to hardware- and circuit-related incidents are shared with the next NOC along the data communication route, performance and multi-domain issues are passed to the PERT (Performance Enhancement and Response Team), where such a team is available within the network.

68% of the PERT cases opened were related to throughput transfer between different countries and 16% were related to packet loss. The problems were mostly encountered by participants of large, international projects.

perfSONAR MDM provides two types of tool that can enable a better understanding of what is happening on the network and thus can speed up the troubleshooting process. Both tool types can be run on the same platform.

Throughput Measurement Tools

perfSONAR MDM uses the BWCTL (Bandwidth Controler) for throughput measurement. The deployment of BWCTL Measurement Points on a well-tuned machine (a machine sending 1Gbps of TCP traffic) within the end-sites allows a number of benefits:

• A dependable baseline (ideally several hundreds of Mbps) against which throughput data results can be compared if a problem arises. This indicates whether the problem is on the network (between the two test servers) or on the remaining path (end-site network or host).
• Operators and users can save time by being able to access already deployed, established tools that can be used on demand.
• To identify if and where packets of data are lost by performing tests using software that is located within the provider’s premises and within the backbone networks.

Delay Measurement Tools

The deployment of delay measurement tools (like, for example, Hades or pinger MP) enables the network operators and systems administrators to:

• Identify the regular path followed and if a re-routing has occurred.
• Find out whether there is any heavy packet loss and if congestion occurs.