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Paul Derby
2003-12-07, 08:25
I've tried to do what you describe a few times. It would work for 10
or 15 seconds, then the music would fall apart. A guess is that the
buffer in the SLIMP3 isn't large enough to keep up with the download
traffic. My test was with a residential Verizon ADSL connection two
blocks from the server.

seanadams
2003-12-07, 17:09
Paul,

Squeezebox uses a more advanced communication protocol, and streams
audio over TCP/HTTP. It works well over WANs.

The limitation with SLIMP3 is not the buffer capacity. It is the
streaming protocol, which is not intended to work over long-distance
WANs. It just can't keep up with higher data rates when the server and
client are far apart, no matter how much bandwidth is there. Usually
though, it does work when the distance across the internet is not too
far, ie when the client and server are connected through the same or
"nearby" ISPs. Geographical distance doesn't matter - it's the network
latency that limits throughput for SLIMP3.

You might have luck streaming at lower data rates though...

Sean

On Dec 7, 2003, at 7:25 AM, Paul Derby wrote:

> I've tried to do what you describe a few times. It would work for 10
> or 15 seconds, then the music would fall apart. A guess is that the
> buffer in the SLIMP3 isn't large enough to keep up with the download
> traffic. My test was with a residential Verizon ADSL connection two
> blocks from the server.
>
>

Craig Brannan
2003-12-07, 19:55
Sean,

Can you elaborate on the benefits that this advanced protocol offers in
a typical LAN environment.

I originated this thread with the question about using the SliMP3 over
a WAN... but your comment on new protocol has me intrigued regarding
what this might mean for LAN operation.

Does this new protocol mean for example that there is less overhead in
the server in serving a stream. The benefit I could see to this would
be the server might be able to handle more simultaneous streams than
would be possible if connecting to SliMP3s using the old protocol. Or
maybe the new protocol requires less network traffic - although I would
imagine the requisite handshaking/framing etc would still be small
relative to the audio data even with the old protocol.

What benefit might a typical LAN user realize due to this new protocol?
I've been thrilled with my Slim - but since you mentioned this - I've
been wondering if there might be any additional benefit in having a
Squeeze - other than the digital out. and (hopefully) having on-board
AAC decoding. I currently have the slim on a wireless bridge so that's
already covered.

Craig.


On Dec 7, 2003, at 7:09 PM, Sean Adams wrote:

> Squeezebox uses a more advanced communication protocol, and streams
> audio over TCP/HTTP. It works well over WANs.

seanadams
2003-12-08, 09:34
Improvements for LANs and WANs:

* Lower server load - transmission is done by TCP so it's faster than
application-level UDP transfer (which we were doing in perl - it works
fine for MP3 data rates, but it uses a fair amount of CPU and would not
be a good idea for PCM streaming).

* Ability to direct the squeezebox to any HTTP source to establish the
streaming connection. We're not using this yet - all connections right
now go through the same server that provides the control connection.
However, we may use this capability later to allow load balancing,
"merging" of libraries between two servers, or even "PC-less" operation
where the squeezebox is directed to internet radio sources by a control
server somewhere out on the internet.

Improvements for WANs only:

* Support for high-latency links

* Plays much better with NAT. With our UDP protocol, different NAT
routers would handle it differently. Some worked fine, others would
time out the "connection" after some time. Now that it's all TCP, it
works fine through NAT.

Also, not really specific to the comm. protocol, but squeezebox has
better setup menus, and will detect and allow you to choose from
multiple servers running on the network.



On Dec 7, 2003, at 6:55 PM, Craig Brannan wrote:

> Sean,
>
> Can you elaborate on the benefits that this advanced protocol offers
> in a typical LAN environment.
>
> I originated this thread with the question about using the SliMP3 over
> a WAN... but your comment on new protocol has me intrigued regarding
> what this might mean for LAN operation.
>
> Does this new protocol mean for example that there is less overhead in
> the server in serving a stream. The benefit I could see to this would
> be the server might be able to handle more simultaneous streams than
> would be possible if connecting to SliMP3s using the old protocol. Or
> maybe the new protocol requires less network traffic - although I
> would imagine the requisite handshaking/framing etc would still be
> small relative to the audio data even with the old protocol.
>
> What benefit might a typical LAN user realize due to this new
> protocol? I've been thrilled with my Slim - but since you mentioned
> this - I've been wondering if there might be any additional benefit in
> having a Squeeze - other than the digital out. and (hopefully) having
> on-board AAC decoding. I currently have the slim on a wireless bridge
> so that's already covered.
>
> Craig.
>
>
> On Dec 7, 2003, at 7:09 PM, Sean Adams wrote:
>
>> Squeezebox uses a more advanced communication protocol, and streams
>> audio over TCP/HTTP. It works well over WANs.
>
>

Sean McGrath
2003-12-08, 13:14
Can the slimp3 firmware be updated to talk TCP to the server?

--
Sean McGrath
sean (AT) manybits (DOT) net

Kevin Deane-Freeman
2003-12-08, 13:23
Quoting Sean McGrath <sean (AT) manybits (DOT) net>:

> Can the slimp3 firmware be updated to talk TCP to the server?

No. The firmware ends at 2.2 for the Slimp3. I would assume this is a hardware
limitation of the Slimp3. Squeezebox looks very similar, but its really a whole
new platform.

-kdf