GCN-XML and Dakota

[Roy Williams]

Dear VOEventers

I am trying to understand the difference between GCN-XML [1][2] and 
Dakota [3][4] as transport protocols for VOEvents.

-- Each sends out VOEvents, although Dakota can also receive events.
-- The GCN seems to emulate the "broker to subscriber" part of Dakota 
(section 3.2), not the other parts.
-- Each uses the uncommon idea that the receiver of the message 
initiates the connection (usually the sender connects).
-- Dakota uses "iamalive" messages whereas GCN uses "imalive" messages 
(note spelling).

It would be great to unify these two seemingly equivalent transport 
mechanisms. One has the events and 20 years of trust, the other has the 
open source implementation.

Your wisdom welcome!
Roy


[1] http://gcn.gsfc.nasa.gov/tech_describe.html#tc17
[2] http://gcn.gsfc.nasa.gov/xml_sock_demo.c

[3] http://www.ivoa.net/Documents/Notes/VOEventTransport/
[4] http://voevent.dc3.com/dakota/index.html

---
Caltech LIGO
roy at caltech.edu
626 395 3670