1. A system, comprising: a memory; and a processor programmed to: track, within the memory, a plurality of service level agreement (SLA) policies and service level definition (SLD) policies applied to a request message of a correlated request/response message pair, comprising the processor being programmed to: build a symmetric policy enforcement context structure during a request message policy enforcement flow of the request message that identifies each enforced SLA policy, each enforced SLD policy, and any enforced policy alternatives executed in association with each enforced SLA policy and each enforced SLD policy; and store the symmetric policy enforcement context structure within the memory; and where the processor is further programmed to: detect a response message of the correlated request/response message pair; identify, using the tracked plurality of SLA policies and SLD policies applied to the request message, a corresponding plurality of platform-specific policy enforcement processing rules used to enforce the plurality of SLA policies and SLD policies on the response message; and enforce the plurality of SLA policies and SLD policies on the response message using the identified corresponding plurality of platform-specific policy enforcement processing rules.