This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter's approach.
Businesses of almost all types are increasingly dependent on service providers for network connectivity that consistently delivers certain performance characteristics. In addition to basic service availability, these characteristics increasingly include peak, average and minimum bandwidth utilization, latency (delay) and latency variation (jitter), and packet loss -- all of which can affect operational efficiency and end user satisfaction. This is especially the case with Ethernet-based service offerings employing packet transport to deliver E-LINE services operating at speeds up to tens of gigabits per second.
Where third-party network services or facilities are concerned, these performance requirements are often written into contractual service level agreements (SLAs) that entail penalties to the service provider if they're not met. In most cases, service providers are required to supply periodic reports detailing the degree to which SLA targets were achieved.
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But it's of little value for IT managers to discover at month-end that certain SLA violations occurred and that they may be due financial rewards. The damage -- to customer satisfaction especially -- has already been done and cannot be corrected by collecting penalties from the service provider.
What network managers need is not just backward-looking SLA reporting -- they need real-time SLA assurance reporting. They need to understand the presence of SLA violations the instant they occur and where they occurred so they can correlate and assess exactly what applications and end users have been adversely impacted.
Better still, if network managers can track actual bandwidth utilization against committed and peak bandwidth agreements, they will be in a position to forecast when additional bandwidth will be required on certain routes. By doing so, they may be able to prevent SLA violations from occurring, which is the preferred outcome for all parties.
For example, network delay is one of the most critical performance attributes since it is visible to users. High network delay is most frequently the result of packet discards and TCP retransmissions, which almost always stems from bandwidth congestion. Network managers with the right real-time monitoring tools can better forecast bandwidth needs and reduce the probability that such events will occur.
Getting at this highly granular level of information in real time requires much closer collaboration with service providers because detailed SLA performance information only exists within service provider networks. However, in the past service providers have lacked many of the mechanisms required to accurately, securely, and cost effectively provide their customer with real-time access to SLA-impacting performance data.