Rán, the goddess of the sea monsters

From: João S. Lopes Filho
Message: 10067
Date: 2001-10-09

What's the etymology of Rán, Aegir's wife? Has she some IE trait?
 
Perhaps similar to Domnu (<*Dubn- "deep"), mother of Fomoire?
 
A PIE goddess/demoness dwelling in submarine bothom, mother of Giants, like the she-monster in Beowulf story?