Streaming Media Supplement sa2150 and sa2250

Chapter 6 Configuring Media-IXT: an Overview

From Media-IXT’s bin directory, run this command for a single Media-IXT host:

./traffic_line -b

From Media-IXT’s bin directory, run this command for a Media-IXT cluster:

./traffic_line -B

Features and configuration files

For reverse proxy caching, you put rules in remap.config.

For hierarchical proxy caching, you put rules in parent.config.

For selective caching, you put rules in cache.config and filter.config.

The rules used in these files differ in format. See the example entries in the table at the end of this section.

Tags and rules

All rules include a scheme parameter or a URL which has a scheme. The scheme is always MMS for WMT

content, and RTSP for RealNetworks or QuickTime content. So, while it is always clear when a rule pertains to

WMT content, there is sometimes a need to distinguish whether a rule whose scheme is RTSP applies to

RealNetworks or to QuickTime. (Remember that both RealNetworks and QuickTime content use the RTSP

protocol. See “About streaming media” on page 2.)

To distinguish whether a rule whose scheme is RTSP applies to RealNetworks or to QuickTime, you have the

option of adding a tag to the rule. The tags are RNI for RealNetworks and QT for QuickTime. There is no WMT

tag. Only use tags when you need to indicate whether a rule applies to RealNetworks or QuickTime content.

Although the tags are always either RNI for RealNetworks and QT for QuickTime, the format of the tag differs

from configuration file to configuration file. See the table below for examples.

Reverse proxy caching and remap.config

Writing correct mapping rules is necessary but not sufficient for reverse proxy to work correctly. The Fully

Qualified Domain Name portion of the URLs of the origin server’s content must contain the advertised name

of the website. And, Media-IXT normally must answer to the advertised name of the website. See

“Understanding forward proxy, reverse proxy, and transparency” on page 6.

For reverse proxy, you put remapping rules in remap.config.

There are two kinds of remapping rules: the map rule and the reverse_map rule.

You can, optionally, add an RNI tag or QT tag to any remapping rule.

You can edit remap.config manually, or use Traffic Manager to configure reverse proxy, including

specifying tags for rules.

The tag format for remap.config is just a space, then the tag, at the end of the rule.

Example:

map rtsp://mymixt.com rtsp://actual-real-server.com RNI

map rtsp://mymixt.com rtsp://actual-quicktime-server.com QT

(Because reverse_map rules are used for WMT only, and there is no WMT tag, tags are never applied to

reverse_map rules.)

The idea here is that RTSP requests are going to the advertised name of the website, Media-IXT is answering

to that name, and then Media-IXT needs to map requests to the correct origin server.

Media-IXT needs to know which origin server is for QuickTime RTSP and which is for RealNetworks RTSP

requests.

There is no similar tag for MMS requests because those always go to WMT origin servers.