[1].In our work, we have focused our attention to enterprise networks and pro-
vide such differentiated service levels in MPLS domain, since we have control
over the network QoS in the enterprise domain as compared to the Internet.
Rest of the chapter is organized as follows. In Section 2.2, we formulate our
problem and then in Section 2.3, we discuss existing approaches.
2.2
Problem Formulation
Increasing importance of QoS for applications highlights the need to have
a differentiated level of services on the network on which these applications
are run. Best-effort networking platforms are not sufficient for this purpose.
Thus, applications that require a certain level of QoS must be able to specify
their requirements in a clear and accurate manner by using QoS parameters.
The values of these parameters reflect the requirements of the application.
These parameters can be stored as a pre-defined profile or can be accessed
through Application Programming Interface (API). Therefore, for a given ap-
plication a user using it should be able to invoke an application QoS profile
which would be mapped to network configurations and the required end-
to-end guarantees would be provided.As an example, suppose an enterprise
client has multiple VPN sites across a MPLS network of a Service Provider.
Now, the service provider should be able to provide requested QoS to the ap-
plications which could be an enterprise application such as ERP, Customer
Relationship Management (CRM) or a video-conferencing and provide end-
to-end guarantee by reserving resources in MPLS domain. The application
QoS profile for video-conferencing should mention high bandwidth, low delay,
13