seedlink protocol 3.1 vs. 3.2 and obspy SLClient

Hi All, attached to this mail is a minimal working script to illustrate my issue

Have there been some changes to the seedlink protocol between v3.1 and 3.2? The reason for asking is that I found out this week that I seedlinkclient I wrote and ran, based on obspy, at the end of last year did not work anymore. Funny enough the script worked as should on a different server than the one I had accessed the last time I ran it, even on the same stream as this is available by both servers.

After some debuging it turns out that the server I used to connect to is not running seedlink 3.2 whilst the one that I can get data from runs 3.1, ergo my question if something changed between the version (as I have no idea what the first server ran half a year ago). The problem can be narrowed down to specifying the start of the data to request (attribute begin_time of th SLClient), if I skip this both server will happily stream data to me.

to demostrate that that it works (well is accepted...) to request data from the seedlink 3.1 server with specified begin_time, run the attached script with
argument "pass1"

to demonstrate that the seedlink 3.2 server also accepts my request given that I do no set begin_time run the script with argument "pass2"

to demonstrate that the seedlink 3.2 server do NOT accept my request if begin_time is set use argument "fail" on the script.

Now of course I could be doing something really stupid here, but then hopefully someone will be kind enough to point it out for me (preferably with some pointer (on where I can read up) on how to do it properly)

Thanks Peter (1 KB)

Protocol is exactly the same. In fact, v3.2 is software version rather than protocol version.

At GEOFON the time window requests are currently disabled. You can also notice the missing "window-extraction" when looking at the capabilities:

$ slinktool -i CAPABILITIES
<?xml version="1.0"?>
<seedlink software="SeedLink v3.2 (2014.071)" organization="GEOFON" started="2016/07/15 12:59:08.5527">
   <capability name="dialup"/>
   <capability name="multistation"/>
   <capability name="info:id"/>
   <capability name="info:capabilities"/>
   <capability name="info:stations"/>
   <capability name="info:streams"/>

For time window requests we recommend FDSNWS dataselect.


Ok, got it