Multichannel -- maximum number of outbound connections -- related to frames/period setting?

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Mike O'Connor

Dec 29, 2022, 6:08:26 PM12/29/22
to Jacktrip-users
lots of folks are starting to explore multichannel, and some of them are coming up with setups that require lots of channels into or out of a location.  i'm bumping into this puzzler as i work on setting them up.

sending more than 8 channels to a hub server with 512 frames/period fails, "waiting for peer" on the client end, "not receiving datagrams (timeout)" on the server end.  changing to 256 frames/period yields a max of 18 connections and so forth (see below). 
- is this due to a packet-size limitation, and thus normal or something else that just spoofed me into thinking that?  

- if my hypothesis is correct, is there a way to calculate this and trap it in an error message, with suggestions on what to do?  

- i just did a little brute-force testing that might yield some targets for such an error message:

512 frames/period - 8 outbound connections work

256 frames/period - 18 outbound connections work

128 frames/period - 35 outbound connections work

64 frames/period - 65 outbound connections work

the preceding were all done on an M1 Mac Mini.  the 2014 Intel Mac could only manage 63 connections 

PS:  is there a request in the queue to make the GUI scroll the (VERY cool) VU meters rather than making a window that's so tall that i can't get to the "disconnect" button.  ;-)

mike o'c

Kenneth Fields

Dec 30, 2022, 1:49:37 AM12/30/22
hi mike,
did you try connecting with ipv6 address? 
I believe that MTU issues are handled differently with IPV6. curious to know.

I always use ipv6 when using jack trip. Is there a reason to use ipv4 ever again?


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Mike O'Connor

Jan 4, 2023, 4:55:16 PM1/4/23
to Jacktrip-users
hi Ken,

sorry about taking so long to get back to you.  alas, i live in the US -- cradle of the internet and yet now home to the worlds most hopelessly backward ISPs.  my fiber-to-the-home connection (from a great rural coop - 1 gig symmetrical) is only delivered over IPv4.  cellular internet (newer infrastructure, different regulations) mostly runs over IPv6, so there's hope for the future.  but for now...  that's what we're fighting.

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