real
`
`A
`
`Healfletwarks
`
`REALPROXY G2 ADMINISTRATION GUIDE
`REALPROXYGZ ADMINISTRATION GUIDE
`
`BETA ONE
`BETA ONE
`
`BTN0005857
`
`
`N E U LIO 1009
`
`BTN0005857
`
`BTN0005857
`
`1
`
`NEULION 1009
`
`

`

`Information in this document is subject to change without notice. Companies, names, and data used in
`examples herein are fictitious unless otherwise noted. No part of this document may be reproduced or
`transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written
`permission of RealNetworks, Inc.
`
`' 1999 RealNetworks, Inc.
`
`RealAudio, RealVideo, and RealPlayer are registered trademarks of RealNetworks, Inc.
`
`The Real logo, RealServer, RealPlayer Plus, RealText, RealPix, RealAudio Encoder, RealVideo Encoder,
`RealEncoder, RealPublisher, RealProducer, RealProducer Plus, RealProducer Pro, SureStream, RealBroadcast
`Network, and RealSystem are trademarks of RealNetworks, Inc.
`
`RealFlash is a trademark of Macromedia, Inc. and RealNetworks, Inc.
`
`Macromedia is a registered trademark and Flash and Shockwave are trademarks of Macromedia, Inc.
`STiNG is a trademark of Iterated Systems, Inc.
`
`ACELP-NET codec used under license from UniversitØ de Sherbrooke. Sipro Lab TØlØcom, Inc. Copyright '1994-
`1997. All rights reserved.
`
`DolbyNet is a trademark of Dolby Laboratories, Inc.
`
`Dolby Digital AC-3 audio system manufactured under license from Dolby Laboratories.
`
`Apple, Macintosh, and Power Macintosh are registered trademarks of Apple Computer, Inc.
`
`Microsoft, MS-DOS, Windows, and Windows NT are registered trademarks and ActiveX is a trademark of
`Microsoft Corporation.
`
`Netscape and Netscape Navigator are registered trademarks of Netscape Communications Corporation.
`
`Pentium is a registered trademark and MMX and the Intel Optimizer Logo are trademarks of Intel Corporation.
`
`Sonic Foundry and Sound Forge are registered trademarks of Sonic Foundry, Inc.
`
`Other product and corporate names may be trademarks or registered trademarks of other companies. They are
`used for explanation only, with no intent to infringe.
`
`RealNetworks, Inc.
`1111 Third Avenue, Suite 2900
`Seattle, WA 98101 USA
`
`http://www.real.com
`
`BTN0005858
`
`BTN0005858
`
`2
`
`

`

`CONTENTS
`
`Overview............................................................................... 9
`How This Manual Is Organized .............................................. 9
`Conventions in This Manual .................................................11
`Additional RealSystem Resources..........................................12
`Technical Support ................................................................12
`
`1
`
`OVERVIEW
`
`15
`
`How RealProxy Works ..........................................................15
`Media Cache Software .....................................................17
`Modes of Operation.............................................................18
`Passthrough.....................................................................18
`Cache Integration ............................................................19
`Bitsave.............................................................................21
`Pull Splitting ....................................................................22
`Requirements for Each RealProxy Mode ............................22
`Interaction with RealServer ...................................................22
`Controlling Client Access..................................................23
`Denying Client Access.......................................................23
`Tracking Activity...............................................................23
`Cache Requests................................................................23
`When RealProxy Will Not Conserve Bandwidth......................24
`Additional Features ..............................................................24
`Administration.................................................................24
`Setting Up Clients ............................................................25
`Limiting Network Traffic...................................................25
`Chaining One RealProxy to Another ..................................25
`Monitoring RealProxy in Real Time....................................26
`Tracking RealProxy Activity ...............................................26
`Protocols.............................................................................26
`
`2
`
`STARTING AND STOPPING REALPROXY
`
`29
`
`Windows .............................................................................29
`Starting RealProxy Under Windows ...................................29
`Stopping RealProxy Under Windows .................................32
`UNIX ...................................................................................32
`
`iii
`
`BTN0005859
`
`BTN0005859
`
`3
`
`

`

` Contents
`
`RealProxy Administration Guide
`
`Starting RealProxy Under UNIX.........................................33
`Stopping RealProxy Under UNIX .......................................34
`Configuring MIME Types .....................................................34
`License Information .............................................................36
`
`3
`
`CONFIGURING REALPROXY FEATURES
`
`39
`
`Configuring RealProxy Using RealSystem Administrator .........39
`Starting RealSystem Administrator....................................39
`Using RealSystem Administrator .......................................40
`Restricting Access to RealSystem Administrator .................41
`Configuration File ................................................................41
`Editing the Configuration File with a Text Editor ................42
`Common Settings ................................................................43
`Port Variables ..................................................................43
`Configuring RealProxy Features.............................................43
`Passthrough Mode...........................................................44
`Bitsave Mode...................................................................44
`Cache Mode....................................................................44
`Pull Splitting....................................................................44
`Multicasting ....................................................................44
`
`4
`
`CONNECTING CLIENTS TO REALPROXY
`
`45
`
`Overview .............................................................................45
`Configuring Clients to Send Requests to RealProxy ............45
`Using a Router to Send Client Requests to RealProxy .........45
`Configuring RealPlayers to Contact RealProxy .......................46
`Configuring RealProxy to Listen for Re-Routed Client Messages47
`
`5
`
`ADVANCED FEATURES
`
`51
`
` Running Web Servers and RealProxy on the Same System ......51
`Administering Both RealProxy and RealServer ........................52
`Reserving IP Addresses for RealProxy(cid:146)s Use ............................52
`Features Specific to the Operating System .............................53
`Windows NT ...................................................................53
`UNIX...............................................................................54
`
`6
`
`MANAGING BANDWIDTH
`
`55
`
`Overview .............................................................................55
`Maximum Clients.................................................................56
`Maximum Bandwidth...........................................................56
`Maximum Gateway Bandwidth .............................................57
`Low Gateway Bandwidth......................................................57
`Limiting Access to Multicast Reception .................................58
`
`iv
`
`BTN0005860
`
`BTN0005860
`
`4
`
`

`

` Contents
`
`RealProxy Administration Guide
`
`Limiting Access by RealPlayer Version....................................59
`
`7
`
`LIMITING ACCESS TO REALPROXY
`
`61
`
`Overview .............................................................................61
`Deciding What Rules to Create .............................................62
`Numbering the Rules............................................................63
`Setting Up IP Access Control ................................................64
`
`8
`
`9
`
`10
`
`11
`
`CHAINING ONE REALPROXY TO ANOTHER
`
`71
`
`Overview .............................................................................71
`Setting Up Chaining .............................................................72
`Turning Off Chaining ...........................................................73
`
`MULTICASTING LIVE STREAMS
`
`75
`
`Overview .............................................................................75
`Multicast Methods...........................................................76
`Setting Up Multicasting........................................................76
`Setting Up the Network for Multicasting ...........................77
`Allocating Addresses and Port Numbers in RealProxy.........77
`Determining Required Addresses and Port Numbers ..........78
`Setting Up Back-Channel Multicasting ..................................78
`
`MONITORING REALPROXY ACTIVITY
`
`83
`
`Using RealSystem Administrator ...........................................83
`
`TRACKING REALPROXY ACTIVITY
`
`85
`
`Proxy Log.............................................................................85
`Reading a Proxy Log.........................................................85
`Customizing Information Reported by the Proxy Log..........91
`Log File Rolling ....................................................................93
`Disabling Log File Rolling .................................................94
`Error Log .............................................................................94
`
`A
`
`CONFIGURATION FILE SYNTAX
`
`97
`
`Configuration File Components ............................................97
`XML Declaration Tag .......................................................97
`Comment Tags ................................................................97
`List Tags..........................................................................98
`Variable Tags...................................................................98
`
`B
`
`CONFIGURATION FILE CONTENTS
`
`101
`
`Editing the Configuration File .............................................101
`Elements of the Configuration File ......................................102
`Ports .............................................................................102
`
`v
`
`BTN0005861
`
`BTN0005861
`
`5
`
`

`

` Contents
`
`RealProxy Administration Guide
`
`Paths.............................................................................102
`RealProxy ......................................................................103
`RTSP Redirection ...........................................................105
`MIME Types ..................................................................105
`File Systems ...................................................................106
`IP Binding......................................................................108
`Allowance......................................................................109
`HTTP Support ...............................................................110
`Access Control...............................................................110
`Splitting ........................................................................111
`Multicasting ..................................................................112
`Authentication...............................................................113
`Passwords .....................................................................114
`Logging .........................................................................114
`
`C
`
`FILES INCLUDED WITH REALPROXY
`
`117
`
`vi
`
`BTN0005862
`
`BTN0005862
`
`6
`
`

`

` Contents
`
`RealProxy Administration Guide
`
`vii
`
`BTN0005863
`
`BTN0005863
`
`7
`
`

`

` Contents
`
`RealProxy Administration Guide
`
`viii
`
`BTN0005864
`
`BTN0005864
`
`8
`
`

`

`INTRODUCTION
`
`This manual describes a pre-release product. As such, some features may not be
`fully implemented; any information here is subject to change.
`
`Welcome to RealProxy(cid:153), a network server that works with
`RealServer(cid:153) to reduce streaming media bandwidth and improve the
`viewing experience on your intranet or Internet gateway. This
`manual will help you use and optimize RealProxy.
`
`Overview
`
`This manual is aimed at information services administrator who will be
`setting up RealProxy.
`
`How This Manual Is Organized
`
`This manual contains the following chapters:
`
`Chapter 1: Over view
`This chapter gives the (cid:147)big picture(cid:148) of how RealProxy streams media to a
`clients, while conserving bandwidth used.
`
`Chapter 2: Star ting and Stopping RealProxy
`This is a guide to starting and stopping RealProxy. Depending on which
`platform your RealProxy runs on, different automatic starting options are
`available. The license structure and MIME types are also discussed.
`
`Chapter 3: Conf iguring RealProxy Features
`RealSystem Administrator is the web-based console for fine-tuning RealProxy
`features.
`
`9
`
`BTN0005865
`
`BTN0005865
`
`9
`
`

`

` Introduction
`
`RealProxy Administration Guide
`
`Chapter 4: Connecting Clients to RealProxy
`There are just a few steps you need to take to set up clients to take full
`advantage of RealProxy. Or, you can set up RTSP redirection so that this
`happens automatically.
`
`Chapter 5: Advanced Features
`This chapter discusses differences between RealProxy on the different
`platforms, the assignment of IP addresses for RealProxy(cid:146)s use, and some
`differences between RealProxy and RealServer.
`
`Chapter 6: Managing Bandwidth
`RealProxy has several methods of managing the amount of bandwidth it uses.
`You can limit the amount of bandwidth in use at one time, and place a cap on
`the number of clients who can receive streaming media.
`
`Chapter 7: Limiting Access to RealProxy
`You can limit which clients use your RealProxy, based on their IP addresses.
`
`Chapter 8: Chaining One RealProxy to Another
`By employing several RealProxies at once, you can funnel all streaming media
`Internet traffic through a single point.
`
`Chapter 9: Splitting Live Streams
`Splitting can distribute load over your network.
`
`Chapter 9: Multicasting Live Streams
`Take advantage of multicasting when streaming from RealProxy.
`
`Chapter 10: Monitoring RealProxy Activity
`To provide highest quality service, you(cid:146)ll want to keep track of how many
`people are accessing your RealProxy.
`
`Chapter 11: Tracking RealProxy Activity
`You(cid:146)ll want to look at trends and see what content is most popular. RealProxy
`can report player behavior with a customizable degree of detail. Errors are
`reported in their own log, which can help you troubleshoot any problems that
`arise.
`
`10
`
`BTN0005866
`
`BTN0005866
`
`10
`
`

`

`RealProxy Administration Guide
`
` Introduction
`
`Appendixes
`
`Appendix A: Conf iguration File Syntax
`This appendix consists of a discussion of the XML syntax used by the
`configuration file.
`
`Appendix B: Conf iguration File Contents
`This is a guide to the configuration file, for those who prefer to edit it directly
`rather than using RealSystem Administrator.
`
`Appendix C: Files Included with RealProxy
`A list of the files installed by RealProxy.
`
`Conventions in This Manual
`
`Because this manual is aimed at the RealProxy administrator, the term (cid:147)you(cid:148)
`refers to the administrator.
`
`RealSystem clients, such as RealPlayer, are referred to generically as (cid:147)clients(cid:148).
`Where information applies specifically to the RealNetworks RealPlayerfi or
`RealPlayer Plus(cid:153), this is spelled out. Although most clients in use are
`RealNetworks(cid:146) own RealPlayer, RealNetworks also makes a software
`development kit that enables other companies to develop their own players
`which can also receive streamed data types.
`
`(cid:147)Clips,(cid:148) (cid:147)content,(cid:148) (cid:147)media files,(cid:148) and (cid:147)files(cid:148) are used interchangeably to
`indicate the material that RealProxy streams.
`
`The following table explains the typographic conventions used in this manual:
`
`Convention
`
`Meaning
`
`Notational Conventions
`
`syntax
`
`value
`
`. . .
`
`[ ]
`
`Syntax of configuration files, URLs, or command-line instructions
`are given in this typeface.
`
`Placeholder words are given in an italic monospaced typeface.
`Substitute the appropriate value for your system.
`
`Ellipses indicate nonessential information omitted from the
`example.
`
`Square brackets indicate optional material. If you choose to use the
`material within the brackets, do not type the brackets themselves.
`
`11
`
`BTN0005867
`
`BTN0005867
`
`11
`
`

`

` Introduction
`
`RealProxy Administration Guide
`
`Additional RealSystem Resources
`
`In addition to this manual, you may be interested in the following
`RealNetworks resources, available at http://service.real.com/help/library/
`index.html.
`
`(cid:149) RealServer Administration Guide
`
`The basic reference for the RealServer administrator, this manual explains
`how to set up, configure, and run RealServer to stream multimedia.
`
`(cid:149) RealSystem G2 Software Development Kit
`
`RealNetworks has developed a Software Development Kit (SDK) that lets
`you integrate applications with RealSystem or create new plug-ins for
`RealServer or RealPlayer. Knowledge of programming is required to use
`the SDK. Register for and download the SDK from
`http://www.real.com/devzone/.
`
`Technical Support
`
`For technical support with RealSystem G2, please fill out the form at:
`
`(cid:149) http://service.real.com/contact/email.htm
`
`The information you provide in this form will help technical support
`personnel to give you a prompt response. For general information about
`RealNetworks(cid:146) technical support, visit:
`
`(cid:149) http://service.real.com/help/call.html
`
`12
`
`BTN0005868
`
`BTN0005868
`
`12
`
`

`

`RealProxy Administration Guide
`
` Introduction
`
`13
`
`BTN0005869
`
`BTN0005869
`
`13
`
`

`

`14
`
`BTN0005870
`
`BTN0005870
`
`BTN0005870
`
`14
`
`

`

` Chapter 1: OVERVIEW
`
`1
`
`This manual describes a pre-release product. As such, some features may not be
`fully implemented; any information here is subject to change.
`
`RealProxy manages clients requests for RealServer content.
`RealProxy can also be integrated with third-party cache software,
`enabling RealProxy to stream stored media closer to clients and to
`conserve gateway bandwidth.
`
`How RealProxy Works
`
`RealProxy is software you install on a network or ISP gateway that aggregates
`and handles client requests for media streamed by RealServer. When installed
`with streaming media cache software, RealProxy reduces network traffic by
`eliminating redundant requests for streaming media.
`
`RealProxy provides two main benefits:
`
`(cid:149) Reducing bandwidth consumption by eliminating redundant data
`transmissions.
`
`(cid:149) Improving quality of service by distributing streaming media close to the
`user.
`
`Over view of the RealProxy Process
`
`1. Clients request streamed media files via RealProxy.
`
`2. RealProxy forwards the requests to the RealServer where the requested
`streamed media files are stored (called the (cid:147)origin RealServer(cid:148)).
`
`RealServer verifies the file(cid:146)s existence, and that the clients are authorized
`through IP addresses or authentication. If RealServer denies the request, it
`does not stream the requested file, and neither does RealProxy. Clients
`receive an error message.
`
`15
`
`BTN0005871
`
`BTN0005871
`
`15
`
`

`

`CHAPTER 1: Overview
`
`RealProxy Administration Guide
`
`This initial transaction, in which RealServer examines and authorizes
`individual client requests, is called an (cid:147)accounting connection.(cid:148)
`
`Steps in the RealProxy Process
`
`3. If the stream is live, and served from a RealServer that supports splitting,
`RealProxy replicates the live stream for each client requesting the stream.
`The origin RealServer sends only a single stream to RealProxy.
`
`If the live stream is not available via splitting, RealProxy delivers the data
`separately for each client.
`
`Live Content
`
`4. If the stream is on-demand, and RealProxy is set up to use a media cache,
`it fills the request from the cache.
`
`If the stream is on-demand, and a media cache is not available, RealProxy
`passes a data stream for each client that requested it.
`
`16
`
`BTN0005872
`
`BTN0005872
`
`16
`
`

`

`RealProxy Administration Guide
`
`CHAPTER 1: Overview
`
`On-Demand Content (No Media Cache in Use)
`
`Media Cache Software
`
`RealProxy can be configured to work with a third-party media cache, which
`will store streamed data for clients requesting these streams later. A media
`cache file lowers network traffic by reducing the number of connections to the
`source of the requested material, and improves quality by distributing the
`streaming content closer to the user. Clients receive improved quality of
`service because media streams travel a shorter distance from the cache to
`clients, reducing the possibility of network congestion or packet loss.
`
`RealProxy and Media Cache Software Delivering On-Demand Streams
`
`Once configured to work with a media cache, RealProxy sends the client(cid:146)s
`request to the origin RealServer. After the request is approved and RealServer
`begins streaming, RealProxy looks at the incoming stream to determine
`
`17
`
`BTN0005873
`
`BTN0005873
`
`17
`
`

`

`CHAPTER 1: Overview
`
`RealProxy Administration Guide
`
`whether it is live or on-demand material. If the request is for on-demand
`material, RealProxy sends the request to the media cache software. The media
`cache software locates the data and streams it to the client.
`
`Modes of Operation
`
`RealProxy has four modes of operation:
`
`(cid:149) Passthrough
`
`(cid:149) Bitsave
`
`(cid:149) Caching
`
`(cid:149) Splitting
`
`In addition, the methods that handle live broadcasts (passthrough, bitsave,
`and push splitting) can be configured to transmit via multicast.
`
`Mode
`
`Passthrough
`
`Caching
`
`Bitsave
`
`Splitting
`
`RealProxy Modes
`
`Streams on-
`demand clips
`
`Streams live
`clips
`
`(cid:149)
`
`(cid:149)
`
`(cid:150)
`
`(cid:150)
`
`(cid:149)
`
`(cid:150)
`
`(cid:149)
`
`(cid:149)
`
`Can be
`configured
`to multicast
`
`Conserves
`bandwidth
`
`(cid:150)
`
`(cid:150)
`
`(cid:149)
`
`(cid:149)
`
`(cid:150)
`
`(cid:149)
`
`(cid:149)
`
`(cid:149)
`
`In passthrough, caching, and bitsave modes, an accounting connection is
`opened between the client and the origin RealServer.
`
`Passthrough
`
`This is the RealProxy(cid:146)s simplest method of operation. In passthrough mode,
`no special features are activated, but all streaming media traffic passes
`through one point. In addition to the usual accounting connection opened
`between the client and the origin RealServer, RealProxy creates a data
`connection for each client. No bandwidth conservation is appreciated.
`
`18
`
`BTN0005874
`
`BTN0005874
`
`18
`
`

`

`RealProxy Administration Guide
`
`CHAPTER 1: Overview
`
`RealProxy in Passthrough Mode (Handling Live and On-Demand Streams)
`
`Cache Integration
`
`Cache software stores on-demand streams from RealServer. Since cached files
`are stored in a proprietary format and cannot be accessed directly, RealProxy
`interfaces with the cache to redistribute the stored media to clients.
`
`When caching is enabled, the media cache software stores streamed data when
`requested by the first client. When a second client makes a request for a
`stream, RealProxy checks with the cache to see if a stored version is already
`present. To ensure that the stored version is the most up-to-date version
`available, RealProxy checks with the origin RealServer to see if a newer version
`exists. After determining that the stored copy is the latest version, RealProxy
`streams the stored copy to the second client.
`
`Only on-demand files streamed by RealServer G2 can be cached. Live material
`is handled as in the most efficient mode suitable(cid:151)bitsave or passthrough (and
`sent via multicast, if available on the network).
`
`19
`
`BTN0005875
`
`BTN0005875
`
`19
`
`

`

`CHAPTER 1: Overview
`
`RealProxy Administration Guide
`
`
`
`RealProxy Filling the Media Cache (Handling On-Demand Streams)
`
`RealProxy Serving On-Demand Media from the Cache
`
`To ensure high-quality data at all times, RealProxy monitors the quality of
`both the cached data it is streaming and the connection between the origin
`RealServer and the client.
`
`Should the data from the media cache become impaired in some way, the
`stream halts and clients receive an error message.
`
`If the accounting connection between the client and the origin RealServer is
`interrupted, RealProxy terminates the stream, and the client receives an error
`message.
`
`20
`
`BTN0005876
`
`BTN0005876
`
`20
`
`

`

`RealProxy Administration Guide
`
`CHAPTER 1: Overview
`
`Bitsave
`
`You won(cid:146)t be able to take advantage of your media cache if clients are
`requesting streams from an origin RealServer which has been configured to
`prevent caching. Clients will still receive the streams, but the media cache
`won(cid:146)t be permitted to store them. When RealServer is installed, all its streams
`are cacheable by default.
`
`Even if a RealServer manager opts to prevent caching of some content (such as
`advertisements), he or she will probably permit it for most items. Since
`RealServers can reach more clients if caching is allowed, managers are
`encouraged to leave all content cacheable.
`
`For specific instructions on configuring a third-party media cache, refer to the
`documentation included with that software.
`
`Bitsave mode is for use with live material. The first time a client requests a
`particular stream, RealProxy contacts the origin RealServer on the client(cid:146)s
`behalf and then sends the stream to the client. The second client to request a
`live stream will receive it directly from RealProxy, and RealProxy will not have
`to obtain another stream from the origin RealServer. The origin RealServer
`has only to serve a single stream to every client that uses a particular
`RealProxy.
`
`The advantage to the client is that the material is delivered from a local
`source. As long as the quality of reception between RealProxy and the origin
`RealServer remains good, the client will receive a high-quality live stream, as
`well.
`
`RealProxy in Bitsave Mode (Handling Live Streams)
`
`21
`
`BTN0005877
`
`BTN0005877
`
`21
`
`

`

`CHAPTER 1: Overview
`
`Pull Splitting
`
`RealProxy Administration Guide
`
`If you have your own RealServer that broadcasts within your network, you can
`configure RealProxy to act as a splitter. RealProxy can then share the
`streaming load with the source RealServer.
`
`Requirements for Each RealProxy Mode
`
`The following table outlines the configuration requirements for each aspect of
`RealProxy operation.
`
`Mode
`
`RealProxy Configuration Your Network Requirements
` (assumes RealProxy is running)
`
`Origin RealServer Requirements
`
`Requirements for Each Feature
`
`Passthrough None.
`
`None.
`
`Caching
`
`Cache is enabled;
`configuration file
`contains media cache
`settings (added by
`cache(cid:146)s setup
`program).
`
`Media cache software
`installed. Refer to media cache
`documentation.
`
`Bitsave
`
`None. RealProxy is
`configured to do
`bitsave at installation.
`
`Network allows UDP
`transport between RealProxy
`and RealServer.
`
`Pull splitting None. RealProxy is
`configured to do
`bitsave at installation.
`
`Network allows UDP
`transport between RealProxy
`and RealServer.
`
`Multicasting Configured to use
`multicast address
`range.
`
`Clients and routers are
`multicast-enabled.
`
`Broadcasting live and/or
`on-demand content.
`
`Has on-demand content, and
`is configured to accept
`requests from caches.
`(RealServers are configured
`this way by default.)
`
`Broadcasting live content.
`Configured for pull splitting
`(the pull splitting method
`allows other RealServers or
`RealProxy servers to
`(cid:147)rebroadcast(cid:148) live content.)
`
`Configured to allow pull
`splitting, with default values.
`
`Broadcasting live content.
`
`Interaction with RealServer
`
`This section describes what happens on the origin RealServer when RealProxy
`forwards a client request.
`
`22
`
`BTN0005878
`
`BTN0005878
`
`22
`
`

`

`RealProxy Administration Guide
`
`CHAPTER 1: Overview
`
`Controlling Client Access
`
`Each time it receives a request, RealServer determines whether it can allow a
`particular client to receive streams, based on the number of available streams
`and bandwidth. In addition, RealServer may be configured to require a user
`name and password for certain material. If the requested material requires a
`password, the user will be prompted for the password. RealServer does not
`begin streaming until it receives the correct password.
`
`Only after RealServer has authorized the client(cid:146)s request will RealServer begin
`streaming. Restrictions imposed by the origin RealServer(cid:146)s administrator on
`client access are always honored by RealProxy. The same is true when a cache
`is in use(cid:151)RealProxy waits for RealServer approval of each request before
`streaming it from the cache.
`
`Denying Client Access
`
`An origin RealServer may deny a request for the following reasons:
`
`(cid:149) The requested material is secured, and the user does not have permission
`to access it
`
`(cid:149) RealServer can restrict access according to IP address, and the client(cid:146)s IP
`address is on the restricted access list
`
`(cid:149) No more connections are available on the origin RealServer. The number
`of connections is governed by the license, and can be further limited by
`the manager of the RealServer.
`
`The client receives a message if it is denied access for any reason.
`
`Tracking Activity
`
`To the origin RealServer, requests made via RealProxy appear identical to
`requests made by any other client, and information about quality of service is
`logged in the log file, just as it is for any other type of connection. Information
`about quality of service comes from the accounting connection between the
`RealServer and the client.
`
`Cache Requests
`
`RealProxy only streams media from the cache after opening an accounting
`connection to the origin RealServer. If the accounting connection cannot be
`
`23
`
`BTN0005879
`
`BTN0005879
`
`23
`
`

`

`CHAPTER 1: Overview
`
`RealProxy Administration Guide
`
`established, or if it is disrupted, RealProxy will not stream from the cache to
`the client.
`
`RealProxy cannot cache content which an origin RealServer administrator has
`configured as non-cacheable. Instead, it will use passthrough mode to deliver
`the material to the client.
`
`When RealProxy Will Not Conserve Bandwidth
`
`Under the following circumstances, RealProxy will be unable to conserve
`bandwidth:
`
`(cid:149) If the origin RealServer is configured to only allow caching on some files,
`or not at all. You have no control over this. (For example, a RealServer
`administrator might prevent frequently updated material, such as
`advertisements, from being cached.)
`
`(cid:149) If the origin RealServer is not configured for pull splitting. RealProxy(cid:146)s
`bitsave mode takes advantage of splitting on the origin RealServer, and if
`the RealServer is not set up to allow splitting, bitsave mode won(cid:146)t work.
`
`In all cases, however, using RealProxy on your network serves to collect all
`streaming media traffic at a single point, so that you can better monitor
`activity and maintain security.
`
`Additional Features
`
`RealProxy contains additional features that make it easy to configure,
`administer, and maintain.
`
`Administration
`
`RealSystem Administrator is a web-based console for customizing RealProxy
`features. You can access via a browser anywhere on your network, using either
`Netscape Navigator version 4.06 or higher, or Internet Explorer version 4.0 or
`higher.
`
`Changes you make using RealSystem Administrator are stored in the
`RealProxy configuration file. This text file is based on Extensible Markup
`Language (XML) and can be edited directly. Because the structure of this file is
`complex, RealSystem Administrator is the recommended tool for making
`changes.
`
`24
`
`BTN0005880
`
`BTN0005880
`
`24
`
`

`

`RealProxy Administration Guide
`
`CHAPTER 1: Overview
`
`See Chapter 3: Configuring RealProxy Features on page 39 for specific
`instructions on customizing RealProxy.
`
`Setting Up Clients
`
`Once you have configured RealProxy, you will need to arrange for clients (such
`as RealPlayer) to send their requests to RealProxy.
`
`There are two ways you can do this:
`
`(cid:149) Configure clients to directly contact RealProxy with their streaming
`media requests. You can send instructions for doing this to users.
`
`(cid:149) Configure RealProxy to intercept client requests. This does not require any
`special client configuration, but it does require the use of software or
`hardware which routes TCP traffic by destination port (such as a layer-4
`switch).
`
`For information on setting up either method, see Chapter 4: Connecting
`Clients to RealProxy.
`
`Limiting Network Traffic
`
`To limit the amount of bandwidth used by