do we want to do similar stuff to ARP?
	to my eye, arptimer() is invoked every 5 minutes, however arpt_down
	timer is 20 seconds.  looks strange (arpt_down entry won't be purged
	until next 5 minutes period comes).  if i'm confused, let me know.

itojun


http://mail-index.netbsd.org/source-changes/2003/06/27/0017.html

sys/netinet6/nd6.c
----------------------------
revision 1.86
date: 2003/06/27 08:41:08;  author: itojun;  state: Exp;  lines: +168 -133
split ND6 cache timer management to per-entry.  increased accuracy,
no O(N) loop.   sync w/ kame