Oracle DB Mac Address or other unique identifier

I am interacting with an Oracle DB using SQL over an ODBC connection. Is there an SQL command I can use to get the MAC address of the server, or something that uniquely identifies the server hardware or software installation. This is so I can be sure (or at least fairly sure) that I'm talking to the same database all the time.

From stackoverflow

• I don't know if you could get the mac address at all. But there are several informations which may help you at the v$instance view.

  SELECT * FROM v$instance;
  

  From Node

• Check http://download.oracle.com/docs/cd/B28359_01/server.111/b28320/dynviews_1086.htm#REFRN30047

  The v$database performance view has a column dbid. This is a rather unique identification number of your database. (ofcourse the name column could be unique as well)

  : That porrage is just right. Thanks!
  From Dvanes