• How will you decide what’s interesting for your science case? That’s a lot of ATels to read... • The faster your follow-up, the (potentially) better your science
eXtensible Markup Language • “defines a set of rules for encoding documents in a format that is both human-readable and machine-readable” • Widespread acceptance means many off-the- shelf tools, libraries and procedures.
send an e-mail, engrave on stone tablets, ... • VOEvent Transport Protocol Alasdair Allan, Robert B. Denny, John Swinbank IVOA Note, Version 1.2 coming soon Draft version on request
to its subscribers • Filter event streams • Any node may provide additional services based on events received • Store in a database • Display on a web page • Perform a follow-up observation(!) http://www.skyalert.org/
is a query language for selecting nodes from an XML document. In addition, XPath may be used to compute values (e.g., strings, numbers, or Boolean values) from the content of an XML document” (Wikipedia) • Comet lets subscribers specify an XPath expression and only forward events for which it evaluates to true (or non-zero) • /*[local-name()="VOEvent" and @role!="test"] • //Who[AuthorIVORN="ivo://lofar.transients/"] • This is a Comet “special”, not an IVOA standard.
securely with Bob ? And sends half to Bob Alice can sign with her key. Bob can verify the signature. A signature guarantees the sender of the message had possession of Alice’s key. She generates a PGP “key” PGP is an internet standard (RFC 4880) with various free & commercial implementations.
bits which make up the message are unchanged <element>value</element><element2>value2</element2> <element>value</element> <element2>value2</element2> • What is the legitimate role of a broker or repository?
B. Denny & John Swinbank, IVOA Note, Version 2.0 coming soon (draft version by request). • Supported by the development version of Comet. • ...will this address all your use cases?
find a VOEvent broker? • How do you get hold of an event given an IVORN? • Time series data model • ... others • Please get involved! http://www.voevent.org/