Framework for Content Distribution Network Interconnection (CDNI)

Abstract

This document presents a framework for Content Distribution Network Interconnection (CDNI). The purpose of the framework is to provide an overall picture of the problem space of CDNI and to describe the relationships among the various components necessary to interconnect CDNs. CDNI requires the specification of interfaces and mechanisms to address issues such as request routing, distribution metadata exchange, and logging information exchange across CDNs. The intent of this document is to outline what each interface needs to accomplish and to describe how these interfaces and mechanisms fit together, while leaving their detailed specification to other documents. This document, in combination with RFC 6707, obsoletes RFC 3466.

Content Delivery Network Interconnection (CDNI) Request Routing: Footprint and Capabilities Semantics

“…Were the volume of FCI updates from dCDNs to exceed the volume of requests to the uCDN, it might make more sense for the uCDN to query dCDNs upon receiving requests (as is the case in the recursive redirection mode described in [RFC7336]), instead of receiving advertisements and tracking the state of dCDNs. The advantage of querying dCDNs would be that much of the dynamic data that dCDNs cannot share with the uCDN would now be factored into the uCDN's decision.…”

“…The goal of this document is to achieve a clear understanding about the semantics associated with the CDNI Request Routing Footprint & Capabilities Advertisement interface (from now on referred to as the FCI) [RFC7336], in particular the type of information a downstream CDN (dCDN) "advertises" regarding its footprint and capabilities. To narrow down undecided aspects of these semantics, this document tries to establish a common understanding of what the FCI needs to offer and accomplish in the context of CDNI.…”

Content Delivery Network Interconnection (CDNI) Media Type Registration

“…The CDNI protocol suite consists of multiple HTTP-based interfaces, many of which transfer various payloads encoded in JSON (JavaScript Object Notation) [RFC7159]. The main interfaces (i.e., CDNI Control interface, CDNI Footprint & Capabilities Advertisement interface, CDNI Request Routing Redirection interface, CDNI Metadata interface, and CDNI Logging interface) are described in [RFC7336]. It is desirable to be able to indicate the type of object carried in the HTTP entity-body without having to register separate media types for each CDNI object.…”

Content Distribution Network Interconnection (CDNI) Requirements

“…The Use Cases for CDNI document [RFC6770] discusses the use cases for CDN Interconnection. The Framework for CDN Interconnection [RFC7336] discusses the technology framework for the CDNI solution and interfaces.…”