Specifications

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Cisco Internet Streamer CDS 2.0-2.3 Software Configuration Guide
OL-13493-04
Chapter 1 Product Overview
Content Delivery System Architecture
“Cache Fill Operations” section on page 1-9. This interaction uses HTTP. Once the content is in the
process of being retrieved by the Web Engine, the Flash Media Streaming Engine uses RTMP to begin
streaming the content.
The following describes the characteristics of caching content using HTTP for RTMP client requests;
1. Origin server-based cache validation is still honored for the cached content.
2. Client-side Web Engine rules are bypassed for the RTMP client request.
3. If HTTP headers from the origin server have the “no-cache” attribute set, content is not cached, and
transparent proxy is performed to stream RTMP.
4. Transparent proxy from HTTP to RTMP is supported. Flash Media Streaming Engine begins RTMP
streaming while content is still being fetched using HTTP proxy mode.
Any HTTP configuration that prevents content from being cached still applies for RTMP requests. The
Flash Media Streaming Engine uses multiple HTTP-based range requests in such cases.
Flash Media Streaming Proxy
The Flash Media Streaming Engine can deliver content acting as an origin server or as a proxy server.
The Flash Media Streaming Engine acts as a proxy server when content cannot be cached due to the
origin server’s configuration or due to the Service Engine’s Web Engine configuration. Content is
ingested and distributed using HTTP, whether the client request for the content used HTTP or RTMP.
Note Any content that does not contain “live” or “vod” in the path is automatically proxied.
Unicast Streaming
The Flash Media Streaming Engine supports unicast flash streaming.
URL Signing
Note Support of URL signing for Flash Media Streaming content requests is a Release 2.2 feature.
Flash Media Streaming supports signed URLs, which adds additional security. The URL signature
generation is based on a key that is a shared secret between the component generating the URL signature
and the component validating the URL signature. The URL signature can be generated by the Service
Engine, another component external to the Service Engine, or the web portal.
For more information about the URL signatures, see the “Configuring URL Signing” section on
page 4-23.