2008/07/26 16:24:59

1 NDlog programs ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
materialize(#link,       10, infinity, keys(1,2)).
materialize(pingRTT,     10, 5,	      keys(1,2)).
materialize(pendingPing, 10, 5,        keys(1,2)).

pp1 ping(@S,D,E)	 :- periodic(@S,E,5), #link(@S,D).
pp2 pingMsg(S,@D,E)	 :- ping(@S,D,E), #link(@S,D).
pp3 pendingPing(@S,D,E,T):- ping(@S,D,E), T = f_now().
pp4 pongMsg(@S,E)	 :- pingMsg(S,@D,E), #link(@D,S).
pp5 pingRTT(@S,D,RTT)    :- pongMsg(@S,E), pendingPing(@S,D,E,T),
			    RTT = f_now() - T.
pp6 #link(@S,D)		 :- pingRTT(@S,D,RTT).
Query pingRTT(@S,D,RTT).


2 Predicates and Schema ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#link(@S,D,E)         #link(@Source,Destination,EventID)
ping(@S,D,E)          ping(@Source,Destination,EventID)
pingMsg(S,@D,E)       pingMsg(Source,@Destination,EventID)
pongMsg(@S,E)         pongMsg(@Source,EventID)
pendingPing(@S,D,E,T) pendingPing(@Source,Destination,EventID,Time)
pingRTT(@S,D,RTT)     pingRTT(@Source,Destination,RoundTripTime)

Events:        soft-state:     
ping	       link	   
pingMsg	       pingRTT	   
pongMsg	       pendingPing

periodic(@S,E,5) predicate denotes an infinite stream of periodic 
event tuples generated at node S every 5 seconds with random
identifier E.


3 Dropping Event ID ~~~~~~~~~~~~~~~~~~~
#link(@S,D)         #link(@Source,Destination)
ping(@S,D)          ping(@Source,Destination)
pingMsg(S,@D)       pingMsg(Source,@Destination)
pongMsg(@S)         pongMsg(@Source)
pendingPing(@S,D,T) pendingPing(@Source,Destination,Time)
pingRTT(@S,D,RTT)   pingRTT(@Source,Destination,RoundTripTime)

pp1 ping(@S,D)		 :- periodic(@S,5), #link(@S,D).
pp2 pingMsg(S,@D)	 :- ping(@S,D), #link(@S,D).
pp3 pendingPing(@S,D,T)	 :- ping(@S,D), T = f_now().
pp4 pongMsg(@S)		 :- pingMsg(S,@D), #link(@D,S).
pp5 pingRTT(@S,D,RTT)    :- pongMsg(@S), pendingPing(@S,D,T),
			    RTT = f_now() - T.
pp6 #link(@S,D)		 :- pingRTT(@S,D,RTT).
Query pingRTT(@S,D,RTT).


4 Dropping Location Specifier
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#link(S,D)         #link(Source,Destination)
pendingPing(S,D) pendingPing(Source,Destination,Time)
pingRTT(S,D,RTT)   pingRTT(Source,Destination,RoundTripTime)

events:
ping(S,D)          ping(Source,Destination)
pingMsg(S,D)       pingMsg(Source,Destination)
pongMsg(S)         pongMsg(Source)

periodic (S,5)

pp1 ping(S,D)		 :- periodic(S,5), #link(S, D).
pp2 pingMsg(S,D)	 :- ping(S,D), #link(S,D).
pp3 pendingPing(S,D,T)	 :- ping(S,D), T = f_now().
pp4 pongMsg(S)		 :- pingMsg(S,D), #link(D,S).
pp5 pingRTT(S,D,RTT)     :- pongMsg(S), pendingPing(S,D,T),
			    RTT = f_now() - T.
pp6 #link(S,D)		 :- pingRTT(S,D,RTT).
Query pingRTT(S,D,RTT).


5 NDlog programs with soft-state -> STANDARD NDlog programs
~~ EMBED Soft-State with Time Attribute ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

soft-state:
link(S,D,Tc,Tl)          link(Source,Destination, Tc, Tl)
pendingPing(S,D,T,Tc,Tl) pendingPing(Source,Destination,Time,CurrentTime, LifeTime)
pingRTT(S,D,RTT)	 pingRTT(Source,Destination,RoundTripTime,CurrentTime, LifeTime)

(Tl=10, from materialize declaration)

events:
ping(S,D,Tc)             ping(Source,Destination, CurrentTime)
pingMsg(S,D,Tc)          pingMsg(Source,Destination, CurrentTime)
pongMsg(S, Tc)           pongMsg(Source, CurrentTime)

periodic (S,5,Tc)
pr  periodic(S, 5, Tc')  :- periodic(S, 5, Tc), Tc' = Tc+5


pp1 ping(S,D,Tc)	 :- periodic(S,5,Tc), link(S,D,Tc',10),
                            Tc' < Tc < Tc' + 10.

pp2 pingMsg(S,D,Tc)	 :- ping(S,D,Tc), link(S,D, Tc', 10)
                            Tc' < Tc < Tc' + 10.

pp3 pendingPing(S,D,T,Tc,10)
			 :- ping(S,D,Tc), T = f_now().

pp4 pongMsg(S,Tc)	 :- pingMsg(S,D,Tc), link(D,S,Tc',10),
                            Tc' < Tc < Tc' + 10.

pp5 pingRTT(S,D,RTT,Tc,10)
			 :- pongMsg(S,Tc), pendingPing(S,D,T, Tc',10),
			    RTT = f_now() - T,
                            Tc' < Tc < Tc' + 10.

pp6 link(S,D,Tc,10)	 :- pingRTT(S,D,RTT,Tc,10).
Query pingRTT(S,D,RTT).