Re: VCCT and CA sniffer

[Rok Sabjan <rok.sabjan@cosylab.com>]

Hi Ned, Matthieu et al.,

thanks for the interest. I asked our expert what would be the benefits 
and here is his answer:

In addition to only filtering CA traffic, the plug-in for Ethereal would 
also be able to 'dissect' the CA packet, that is, give meaning to the 
plain hex-codes. Thus, every CA packet would have fields revealing 
CA-specific information, such as:

 * what CA command is in a packet (CA_PROTO_SEARCH, 
CA_PROTO_READ_NOTIFY, ...)
 * what are the parameters of the command (channel name being sought 
for, channel name that was resolved, the value of the field that was 
returned, ...)
 * ...

Then, filtering and searching operations could also be made relative to 
those fields. Example filter:

  "find all packets that concern record ABCD"

I hope this is interesting enough. If you need additional information, 
please let me know.

Best regards,
Rok



Matthieu Bec wrote:
> Hi Ned,
>
> Could we get a bit more description, maybe a draft from Cosylab what the 
> plugin could possibly do? It sounds very interesting.
>
> Regards,
> Matthieu
>
> Ernest L. Williams Jr. wrote:
> > On Fri, 2006-08-18 at 14:59 -0400, Matt Bickley wrote:
> > > Ned Arnold wrote:
> > > > All -
> > > >
> > > > COSYLAB is interested in adding Channel Access support to Ethereal 
> > > > (an open source protocol sniffer) ... for a small fee of course.  
> > > > I'd like some feedback on whether this seems useful ... and how much 
> > > > your institution would be willing to pitch in.
> > > >
> > > > It would be one way to feel a little more independent and confident 
> > > > in one's ability to investigate site-specific communication 
> > > > anomalies, so it has a real payback for your project.
> > > >
> > > > Send comments <and checks> to tech-talk.
> > > We already use ethereal, and it has been very helpful for us
> > > in diagnosing network issues and in making us aware of poorly
> > > behaving clients.  You have to wade through a lot of
> > > extraneous traffic to find the CA-relevant, however.  If
> > > ethereal had CA support, the tool would be easier to use by
> > > anyone, not just network protocol experts.
> > What we have done is to create some nice filters using ethereal to pick
> > out the EPICS CA TCP and UDP traffic.
> >
> >
> > Thanks,
> > Ernest