Customer’s View Versus Provider’s View
Most customers view the network as a secure pipe through which their traffic travels. The fact that many other customers use this pipe is of little interest. This abstraction is one of the major merits of MPLS—the customer view is really simple. The complexity resides in the provider network. This complexity is in turn minimized by the fact that MPLS reduces the need for legacy devices and facilitates scalable services, such as VPNs.
Given that many customers have such a simple view of the network, the provider can add value with a feature called customer self-service. This can take the form of a customer-browseable web page that shows the main elements of the SLA. If an SLA violation occurs, it can be recorded on the web page. Likewise, if a customer decides to update some service parameter, such as the allocated bandwidth, this change can be made via the web page. The modification can be acknowledged and then cascaded through the provider’s network management system. In this way, the customer requirements can be fulfilled in a manner that masks the complexity of the back-end systems.
While customers have many requirements of their service providers, the latter also have requirements that they apply to their networks. Let’s take a quick look at some of these issues.