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FAQ - Frequently Asked Questions
PeerStream 5 Audio/Video Streaming Server
PeerStream 5 Distributed Network Option / Relay Server
General Questions
Is there a demo / evaluation version of the software available?
No, currently there is no evaluation version available. Instead of it you can have a look at our audio and video demo streams. If you have some
specific technical questions, feel free to contact us!
My WMA / WMV / Real streams don't work in Multicast mode, whats wrong here?
Some media formats including WMA / WMV / Real come in different flavours. Although all of them have the same name some completely different encoding
methods are possible. For Multicast streams they in every case have to be encoded in a streamable format so that a client is able to synchronize
with that stream from every position. Please refer to the documentation of the appropriate encoder software for details about how to encode in a
streamable format.
I'm using a playlist with Multicast mode but the player XYZ stops after replaying one file!
Some file formats like WMA / WMV / ASF do contain a length information. If you're using a playlist with data that contain the length of only one
media file some players behave wrong and stop replaying after that length was replayed. Thats a problem with the players. To solve it you can
choose a different player or try to put all the data into one file and avoid the usage of a Multicast playlist.
Is the file format XYZ supported?
You can find a general overview about the supported file formats at the main page, some more specific information are available at the
Audio Streaming Page and the Video
Streaming Page. The formats listed there are the ones that are known to the software directly. Beside of that not directly supported media formats
can be used too. Via some specific options it is possible to define MIME-type, bitrate and other values for such a custom format so that the software
is able to work with them. The only precondition for the data is that they have to be a streamable media format really.
What protocol is used by the PeerStream 5 server software?
The software uses the standard protocol that is supported by all common players: RTP. Thats mainly a HTTP-encapsulated
data stream plus control information plus an optional UDP-connection for title information (in case the connected player
supports that).
Is the number of media suppliers limited that can connect to a single server?
The number allowed suppliers is not limited, you can connect as much as you want - or better as much as makes sense for an
streaming application.
Does the server support transcoding / is it possible to provide only one media file and the server converts it to several other formats and bitrates?
No, thats not supported because thats not the task of a server software. Converting data from one media format to an other is an operation that consumes
much computing power. Server hardware typically provides a high data throughput and high storage capacities while the available computing power is
relatively low. So the process of transcoding would let the hardware requirements explode and would the total costs let rise unnecessarily.
Instead of that there are no additional costs if different files in different bitrates are provided instead because the storage space for servers
is cheap comparing to the other parts.
Which codecs does the server support?
Codec is a short term for "coder / decoder" and describes a piece of software that is able to unpack and create specific media formats.
Except to the LIVE-variant and its on the fly encoder "flyencd" no encoding or transcoding is performed by the software, so no codecs are required. Supporting
the different media formats is done using a different method that does not require any decoding process so full support of all important media formats
is available completely wihtout any native codecs.
Which authentication method is used when user accounting is enabled?
The user authentication method uses HTTP Basic Auth or - for these clients that do not support it correctly - special mountpoints that contain the
authentication data.
What can the user authentication be used for?
With the user authentication every kind of accounting can be performed. It is available for unicast streams as well as for multicast streams. That means
it is possible to implement every pay-per-view model. In general the authentication mechanism works with several usernames and passwords that can be
configured easily and automated within a separate settings file. For every user account that is created this way an own log file is generated during
runtime that contains the information when a user connected, when he disconnected, how much and which data he retrieved and how long he was connected.
Using this information accounting can be done easily and for all imaginable models.
When starting the Application I get an error "libxxx.so.y" can't be found"!
You get that version where "xxx" is the name of the library and "y" a version number: These version numbers of used libraries sometimes change.
After the PeerStream 5 supports several different operating systems that often do not use the same library versions it might happen that a specific
version is not available on a system. In this case a symlink has to be created from the existing library version to the one that could not be found to
solve that problem. E.g. if a library is located in /usr/lib and the application looks for libxxx.so.2 while only a libxxx.so.4 exists following
commands solve the problem:
cd /usr/lib
ln -s libxxx.so.4 libxxx.so.2
Isn't a distributed network (P2P) illegal?
Distributed networks / Peer-2-Peer in general are only a specific method of data transport within a network. Thats nothing that can be illegal. The only
point is that there are many file sharing applications that use P2P technologies where the user share copyrighted material - and thats the illegal part.
So not the technology is the problem but the contents that are provided by the users. For a streaming server the situation is different: here the provider
of a stream is repsonsible for the streams content - independent from the fact if the data are distributed via conventional server-client-connections or
within a distributed network.
Beside of that the PeerStream 5 P2P Relay option does not save any file on a peers local disk so it in no case can be compared to a file sharing application.
Isn't Peer-2-Peer too slow for streaming?
No, the PeerStream 5 distributed network uses a special protocol that is very fast and therefore fits perfectly for streaming applications.
Other P2P-applications are slow for two reasons: the low upstream bandwidth of some connected peers and massive data transfer because of huge amounts of search requests.
Both can't happen within a PeerStream 5 distributed network: the upstream speed of every client is checked and only these ones are used that
are fast enough and aimless search requests that travel over all connected peers doesn't exist here.
How many clients can I reach when I allow n direct connections to my distributed streaming (P2P) relay server?
Thats not predictable because it highly depends on the upstream capabilities of the connected client peers. In worst case - when all client peers
don't have an upstream speed that is fast enough for the stream or when all of them are blocked by firewalls completely - you can reach only n clients.
In best case - when there are enough client peers with a good upstream bandwidth that do not block the stream - the number is unlimited. In practice
you should reach a one-digit multiple of n client peers (x*n where x is in range 2..9).
Can I send live streams over the P2P network?
That depends on the exact application. A P2P network works in that way that the stream data are handed over from one clients peer to an other one. That
process adds a delay of several second to the stream for every peer that is handling it. So depending on how long such a peer queue is there might a
bigger delay for the last peer in this queue.
Resulting from that, if you have an application where live grabbed data are streamed but where it is not important that all peers receive them at the same
time the P2P relay can be used for live streaming. But if you have an application where the timing is important (e.g. because people can call in by phone
for some live conversation) it will not work due to the unpredictable lag that is different for every peer.
Are all media formats supported in every streaming mode that is available (Unicast/Multicast Streaming, UPnP, Distributed Network)?
In principle yes, but for some formats like WMA / WMV / ASF / AVI there might be some heavier preconditions so that they can work (please refer question
2 and 3 above).
To say it in some general words: in Unicast or UPnP streaming mode the media format and encoding method
are less important than in Multicast streaming mode, MPEG media formats are less critical than others and Flash videos only work embedded into
a webpage because they need a separate player that has to be downloaded too. On the other hand there are also limitations on client
side so for an example only some players are able to replay MPEG video streams correctly, here the MediaPlayer fails to handle some of them. So
it might be important for you to check the formats you want to use and the compatibility of the desired players.
On which operating system does the software work?
The software works on all operating systems:
- RedHat Enterprise Linux, Fedora Core 8 or higher, CentOS 5 or higher and compatible
- Sparc Solaris 8 and higher (on request)
- Windows 98 and higher
My server fails with an logfile message "ERROR: could not check license, exiting"
The PeerStream 5 servers validate the license using the license key you received after purchasing it. This check is done online, they contact the license verification
server during runtime. For that operation the outgoing port 17000 or 80 (TCP) needs to be open.
If the server software is not able to check the license
because this connection is blocked by a firewall, because there is no internet connection or for any other network-related problem the execution
of the PeerStream 5 server will fail with this error message.
Is the server available to stream/relay H.264 data/other specific codecs?
Here a difference has to be made: a codec describes how to compress and encode media data in its very specific way, a container
defines the structure encoded data are transported within. For a server software the container format is important, the contained,
encoded data are mainly ignored. H.264 is a codec, not a transport container, therefore both server variants (A/V and P2P) do
not handle them in a specific way. That means when the H.264-encoded data/data with an other specific codec are contained in a
format that is supported by the software (like MPEG, WMV, AAC or others) there is no problem in using that format.
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