[kepler-dev] different versions of SSH actors

[Bertram Ludaescher]

I noticed there are different versions of Kepler SSH actors out
there. If I'm not mistaken, the two most recent versions are
authored/co-authored by Norbert and Efrat, respectively.

Would it make sense to try and consolidate and unify these?

Maybe the authors could send a quick summary of what each of these can
and can't do. I recall that Norbert's version can maintain a single
SSH session throughout multiple actors (btw, without showing the "cable"
between them..) while Efrat's version can re-route stdin and stdout
out.

thanks, cheers

Bertram

PS Additional info follows: One way to think about this is that both
have currently different "standard uses". Here is my cartoon for that:

"OLD" SSH (Ilkay, then extended by Efrat?): 

- can redirect Kepler output to stdin of remote command, i.e.,
"ties" the remote process into the Kepler dataflow: 

R       RX1           RX2
DATA    /\            /\
K --A---PA1----B--C---PA2--> D --> 

"ALTERNATE" SSH (Norbert): 
- can reuse an open SSH session

R   --- RX1 ----------> RX2 ---->  ...
CTRL    /\              /\
K--A---PA1-----B--C----PA2---> D --> 


Here R stands for the remote site, K stands for Kepler site.
In the first setting, data is routed through Kepler;
in the second setting, control is routed through Kepler.