This has been happening over the past 2-3 weeks.  In something like 24-hour intervals,  computers in the house using wifi cannot connect.  My son’s laptop,  when he wakes up at 1 in the afternoon,  cannot connect,  so restarting the router fixes that.  As this kept on happening every day,  I began to notice other things.  My laptop,  sitting right next to my desktop monitor,  but using wifi,  is still online,  and has been all morning.   That led me to believe,  at the beginning of this problem,  that it was a problem with the wifi on my son’s laptop.   Soon,  I noticed that my netbook,  which I usually only fire up 3 or 4 times a week since getting my iPhone,  also had no wifi connection.  It too came back with the restart of the router.  Next,  I discovered that the iPhone also had no wifi connection,  which also returned with a router restart.

What seems to be happening is that the devices that are not on and connected to the Internet are the ones who cannot “reconnect” when they are turned on or awakened (my iPhone is always ON,  but usually asleep).  This was later verified when my laptop that usually maintains its connection throughout the morning,  was turned off until later in the morning,  and it too could not connect when I first turned it on.  So it is only new connections that are denied -  iow,  nothing is “dropped”,  but no further “connections” are allowed.  It’s like some signs of activity have to be seen,  or else my router refuses to hand out a new connection AFTER this “once every 24 hours event” happens.  So ,  computers that are connected and active remain connected,  but the “absent” computers are denied connection when they request it upon being turned on.  Sounds like a DHCP problem, perhaps?