9. Extensibility Considerations

Extensions to IP proxying in HTTP can define behavior changes to this mechanism. Such extensions SHOULD define new capsule types to exchange configuration information if needed. It is RECOMMENDED for extensions that modify addressing to specify that their extension capsules be sent before the ADDRESS_ASSIGN capsule and that they do not take effect until the ADDRESS_ASSIGN capsule is parsed. This allows modifications to address assignment to operate atomically. Similarly, extensions that modify routing SHOULD behave similarly with regard to the ROUTE_ADVERTISEMENT capsule.