Ethernet Switch- what's the point?


I run an Ethernet cable between my router (standard issue from Verizon) and my streaming transport. I note that some use an ethernet switch between between the router and streamer. Assuming I got that right, what is the point- what does a good switch do? I've been into audio since the 70's but when its comes to streaming, I'm definitely a newbie- 

Thanks all!

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Showing 3 responses by tonix

@carlsbad2

Exactly. Most audio/video protocols are based on UDP. More they are real-time, more they use fast protocols which cannot permit to make any check.

TCP/IP controls correctness of every packet and the order in which packets are received. Every x packets, an "OK" packets is sent back to the origin, stating trasmission is ok, delete old packets in buffers and to go on with new packets. Otherwise a "request" to retransmit is sent back is a packet is faulty or missing. All this is expensive and heavily compromizing for the quality requested to a simply phone call. This dialog is between the origin and the end point, crossing all intermediate routers/switches and any communication equipment.

UDP instead does not control any packet, does not control any flow. If a packet is missing or faulty, it's simply gone. It's better to skip it instead of requesting it again.

Every commercial transaction, every printer dialog, any USB disk uses the TCP/IP protocols.
The most of audio/video quality communications use UDP protocols.

Just to make it more clear, a packet coming from a whatever source (TIDAL, qobuz, etc) needs at least 25 ms in the best situation, and more than 100ms in a normal situation. So what you are playing is something sent to you a lot of milliseconds before. Using UDP, you receive a constant stream, with a very regular flow. Using TCP/IP you will freeze the sound every X packets, and also when ask to resend a packet. This latter situation is totally unnoticeable in a commercial transaction, but would be a disaster feeding a DAC. Of course you may use very large buffers, but starts to be a file transfer more than a streaming.

#fredrik222

https://en.wikipedia.org/wiki/Streaming_media
https is TCP/IP, very large buffering, nothing compareable to real-time o live streaming. Probably in your life you never made a video conference using TCP/IP, otherwise you'd know the effects.

@fredrik222

Question is very simple. If you are using a very unefficient protocol like https, which relies on heavy buffering, all is reduced to the quality of client (the webplayer most likely). So, which switch/router/cable to use is no sense question.

If you are changing router/switch/cable and you hear big differences, logic says you are using a UDP like protocol, or the https client is extremely poor.

My 2 eurocents.