Abstract This document provides an overview of the functionality and relationship of the protocols implemented in the Windows Peer Content Caching and Retrieval framework, which includes the protocols specified in , , , , , , and . This framework is based on a peer-to-peer discovery and distribution model designed to reduce wide-area-network (WAN) link bandwidth utilization and provide faster content downloads from a local area network (LAN) in a branch office. The Content Caching and Retrieval protocols support scenarios such as accessing content from a file server or a web server where storing content locally from all locations in a distributed environment is not practical. If the Content Caching and Retrieval of data is unavailable or fails, normal file access would continue without caching using the SMB 2.1/2, HTTP, or HTTPS protocols. This document describes the intended functionality of the Content Caching and Retrieval protocols and how these protocols interact with each other. It provides examples of some common use cases. It does not restate the processing rules and other details that are specific for each protocol. Those details are described in the protocol specifications for each of the protocols and data structures that belong to this protocols group.
Version 2.1 Protocol protocols that are for metadata retrieval. Peer Content Caching and Retrieval: HTTP Extensions Specifies a content encoding as PeerDist that is used by an HTTP/1.1 client and an HTTP/1.1 server to communicate content to each other. The primary role in Content Caching and Retrieval is metadata (hash) retrieval. File Retrieval Server Message (SMB) Version 2.1 Protocol SMB2 version 2.1 and HTTP (as described in [MS-PCCRTP] specifies content encoding over HTTP) are the two protocols used for file retrieval that are content caching Peer Content Caching and Retrieval: HTTP Extensions Specifies a content encoding known as PeerDist that is used by an HTTP/1.1 client and an HTTP/1.1 server to communicate content to each other. The primary role in Content Caching and Retrieval is metadata (hash) retrieval. Content Identification Peer Content Caching and Retrieval: Content Identification A binary data structure that is used for content identification.
Content Discovery Peer Content Caching and Retrieval Discovery Protocol Based on the Web Services Dynamic Discovery protocol There are two modes of operations in WS-Discovery: client-initiated probes and service-initiated announcements; both are sent through IP multicast to a predefined group. Content Retrieval Peer Content Caching and Retrieval: Retrieval Protocol Content in the form of blocks is transferred by HTTP, with the message format, as described in [MS-PCCRR]. Authentication Transport Security (TLS) Hosted server authentication uses HTTP/HTTPS for secure transport of hosted content, as described in describes the Windows implementation of TLS. [MS-TLSP] RFC 4559 Client authentication, as described in . When a hosted cache server is used, client authentication can be enabled. [RFC4559]
Hosted cache: If a hosted cache is to be used, the location of the hosted cache (Domain Name System (DNS) name or IP address) and the hosted cache Listen and Connections Ports is configured on the client computers. System Influences The Content Caching and Retrieval protocols can be influenced by the external systems and components that are shown in the following table. External entity Content Caching and Retrieval protocols depend on an external entity for Consequences if absent Authentication Services system Authenticating client and server principals. Centralized identity management does not work if the Domain Interaction System is not available. Group Policy system Configuration of individual capabilities within the Content Caching and Retrieval protocols. Cannot centrally configure some functionality of the system. Domain interaction system Content Caching and Retrieval to operate either in a domain or in a workgroup. Domain services are required for hosted cache client authentication. Hosted client authentication cannot function. File Access system File Access Services to which Content Caching and Retrieval is an adjunct. No file access and therefore no Content Caching and Retrieval. Web server HTTP Content Caching that depends on the availability of content that is delivered via HTTP. No HTTP content caching can be performed.
Index A Actors 23 23 49 19 20 11 23 C 40 60 7 Coherency requirements 47 non-timer events 42 42 47 timers 41 41 21 21 21 21 21 11 27 Considerations 49 48 49 49 48 49 7 D Dependencies 21 21 Design intent 23 27 25 30 27 24 24 24 25 E 21 40 40 41 40 41 Examples reading file using 53 50 Extensibility 58 40 21 F Functional 11 19 11 11 G 7 H 40 40 41 40 41 I 58 48 49 49 48 49 22 9 Initial 30 23 23 47 7 M 58 O Overview 11 19 20 11 12 22
P 23 58 R Reading file using 53 50 9 47 Requirements coherency 47 non-timer events 42 42 47 timers 41 41 40 40 41 40 41 11 23 19 S 48 49 49 48 49 19 Summary use case descriptions 27 24 Supporting actors and system interests summary 24 System 11 12 dependencies 21 21 21 errors 40 41 40 41 22 24 overview 7 7 7 20 requirements 19 use cases 23 27 25 30 24 24 11 21 21 21 40 20 11 System use cases 23 27 24 25 T 20 60 U Use case diagrams 25 Use cases 23 27 25 30 27 24 24 24 25 V Versioning 58 40