From: YOSHIFUJI Hideaki / 吉藤英明 [off-list ref]
   Date: Sat, 31 May 2003 11:02:49 +0900 (JST)
   
   Again, what I proposed was to store prefix information on fib with 
   some flags to represent advertised by routers and give user-space 
   the RA information using new rtattr (RTA_RA6INFO or something like that).

This sounds very reasonable.