why not start with the basics - check that you have a resolvable route to the 172.16 network from the layer 3 device in the 192.168 network, Also check you have a route back from the 172.16 network to the source. Try a traceroute to see how far your you can get, from both directions.
try pinging the device in the 172.16 network from itself to verify if it is pingable.
That lot should show up something, if not come back!
i tried pinging the 172.16 nw from router it pings,tried pinging it from the core switch but it doesnt.i am unable to ping it even from the utm..the utm pings up till the router i/f eth0/1 172.16.0.99 but no further.
had added accesslist on eth0/0 i/f to permit in 188.8.131.52/24 and permit out 172.16/24 nw.
actually what we require is just to monitor an application in 172.16/24 nw from 192.16/24 network.at the router, there is no route to 172.16/24 nw from 192.168/24 network.do we require a route to 172.16/24 network ?.....where should the route be included?...the core switch or router ?..the core switch has route till utm i/f.