Research by pinging the entire Internet

[#1]

I've noticed that some of the incoming ping packets that might end up in your router's log are apparently from American universities pinging the entire Internet:
IN=ppp0 OUT= MAC= SRC=128.9.168.98 DST=87.113.my.ip LEN=32 TOS=0x00 PREC=0xA0 TTL=48 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=64324 SEQ=4505
128.9.168.98 = pinger-w3.ant.isi.edu
There were some other IPs related to the same project on 8/9 July:
203.178.148.19 = pinger-j2.ant.isi.edu
129.82.138.44 = pinger6.netsec.colostate.edu

[#2]

They're mapping the net...are they doing it for our benefit or for the benefit of government.  
I came across this yesterday...a hacker pinged computers across the world to create a map of the net.Although he only pinged Linux based pc's which seems a bit odd.
Interesting map he created though... http://motherboard.vice.com/blog/this-is-most-detailed-picture-internet-ever

[#3]

Quote from: Glenn

Although he only pinged Linux based pc's which seems a bit odd.

That's not what he did, he only installed his scanning software on suitable Linux devices (maybe routers, printers etc.) that had admin/admin or root/root as the login/password.