Intent Based Service Chaining API

The Intent-based API for Service Chaining allows client applications to prescribe the sequence of service functions that need to be applied to traffic between a source endpoint and a destination endpoint. The Intent API is based on an Intent model which includes the following entities:

1. Intent. The Intent-based API for Service Chaining allows client applications to prescribe the sequence of service functions that need to be applied to traffic between a source endpoint and a destination endpoint. An Intent consists of the source composite Endpoint, the destination composite Endpoint, and Intent Operations.

2. Intent Operation. This is the operation applied to the traffic that matches the source and destination composite endpoints. An operation may refer to a service chain, access control, a QoS operation, etc.

3. Composite Endpoint (CEP). A composite endpoint consists of a Boolean expression consisting of operands (terms) and the Boolean operators: and, or, not. The Boolean operands are registered endpoint descriptor ids and/or the ids of other composite Endpoints. Parentheses may be used for the purpose of grouping. For example:
Composite Endpoint = "(EPD1 or EPD2) and not CEP22"

4. Endpoint Descriptor (EPD). Each endpoint descriptor has a type and value that are used to partially identify the endpoint. The EP descriptor id is used as an operand (term) in a composite EP's Boolean expression. The type of the EP descriptor may be a base networking identifier, such as Layer 3 IP address, or a user-defined type. The value may a single value, a range of values, or a group of values.

5. Service Chain Specification. This is a Service Chain specification associated with the “ServiceChain” Intent Operation. The specification consists of an ordered list of Service Functions.