Specifications

2-9
Cisco TV CDS 2.5 ISA Software Configuration Guide
OL-24788-01
Chapter 2 Network Design
CDS Workflow
immediately, and does not wait for the ten-second report interval. For example, if the server is given 100
Mbps and the streams that were just started uses 90 Mbps, the upper threshold limit has been reached
and the server asks the bandwidth manager for more bandwidth.
A separate entry is maintained for each thin pipe with a list of servers that have the same thin pipe
configuration. Servers that belong to the same thin pipe are added and removed as they become reachable
or unreachable.
The bandwidth manager service runs on each server in either the primary mode or the passive mode. The
one server at the site that is running the primary mode is selected through a discovery mechanism. The
primary bandwidth manager maintains all the thin pipes and associated server structures. If the server
running the primary bandwidth manager fails or loses connectivity, the newly elected bandwidth
manager takes over and when the old primary bandwidth manager becomes available again and
connectivity is restored, the thin pipe information and structures are deleted from the old primary.
All bandwidth manager messages are logged in the bwm.log file. The following logging levels are
defined (default level is Information):
• Critical
• Error
• Warning
• Information
• Debug
• Debug Verbose
Streamer Workflow
A Stream Group is a configurable group of Streamers that are designated to serve specified QAM
devices, and subsequently, specific service groups. From a session setup and control perspective, there
are three logical types of servers in a Stream Group:
• Setup server
• Control server
• Play server
The Setup and Control servers have both a primary and a backup server. The primary server services all
messages, while the backup server simply maintains states. If a primary server is unreachable, the
backup server takes over control and creates another backup server. Thus, there is always a primary and
backup pair of servers for setup and control. The Play server does not have a backup server. However,
the Control server selects a new Play server in the event of a failure of the existing Play server.
Note The ability to have both a primary and backup server depends on the number of Streamers in the Stream
Group.
The Setup and Control server IP addresses are configurable. For an ISA environment, the Setup IP
address is the same as the Stream Master IP address. For RTSP, the Setup server and Control server must
be the same server. For both ISA and RTSP environments, the Stream Service selects a Streamer in the
Stream Group to be the Setup server, and another Streamer (sometimes the same Streamer) to be the
Control server.