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
Codecs
The Flash Media Streaming codec that is supported in Release 2.1 is On2 VP6. The Flash Media
Streaming codecs supported in Release 2.2, in addition to On2 VP6, are listed in Table 1-4.
Live Streaming
Note Live streaming using Flash Media Streaming is a Release 2.2 feature.
Flash Media Streaming uses RTMP to stream live content by means of dynamic proxy. Configuration of
live or rebroadcast programs is not required. When the first client requests live streaming content, the
stream is created. There are no limits to the number of live streams other than the system load. Live
streaming uses distributed content routing to distribute streams across multiple Service Engines.
Upon receiving a client request for live content, the edge Service Engine does the following:
• If the live stream is already present, the edge Service Engine attaches the new client to the existing
stream. No message is sent to the origin server and no connection is set up.
• If the live stream is not present, CDS creates a connection to the origin server to get the stream. No
client information is sent to the origin server.
No per-client control connection is present between edge to origin server for live streaming.
For Flash Media Streaming, a delivery service can be used for prefetched content, cached content,
dynamically cached content, and live content. Because Flash Media Streaming uses dynamic proxy to
stream live content, no disk space is used to store content. A Service Engine can act as the origin server
origin server for streaming live content, provided the SE designated as the origin server is not assigned
to the delivery service that is streaming the live content.
The Flash Media Streaming Engine automatically retries a connection to the origin server if the upstream
live-splitting connection fails. This failover does not require any additional retries from the client side.
Clients see a subsecond buffering, after which video continues to play. This feature does not address
failover when the Service Engine that is streaming to the client fails. The primary advantage is increased
resiliency in the CDS infrastructure. In other words, if a Service Engine fails, the downstream Service
Engine automatically connects to the origin server.
Table 1-4 Codecs Supported in CDS Releases 2.2 and 2.3 for Flash Media Streaming
Standard Details
ISO/IEC 14496-3 MPEG-4 Part 3, also known as AAC+, HE-AAC. A set of compression codecs
for perpetual coding of audio signals, including some variations of Advanced
Audio Coding (AAC), as well as AAC Main, AAC LC, and SBR.
ISO/IEC 14496-10 Advanced Video Coding (AVC), also known as H.264/AVC.
All levels of applications are supported, Base (BP), Main (MP), High (HiP),
High 10 (Hi10P), and High 4:2:2 Profile (Hi422P).
This standard is technically identical to the ITU-T H.264 standard.
ISO/IEC 14496-12 ISO Base Media File Format. A file format for storing media content
containing one audio track (either ISO/IEC 14496-3 [AACPlus] or MP3), and
one video track (either ISO/IEC 14496-10 [H.264 or AVC] or VP6).
3GPP TS 26.245 Time text format