The PPDG does not provide links, they come from ESnet, NTON, MREN etc.
Particle physics is a network hungry application.
Need to access data across WAN making data analysis from hundred of US universities. The first year deliverables will probably not be very useful to others. Part of the goal is to allow high speed bulk transport to occur while not preventing other work. We are working with ESnet and there is a research test bed. A typical site has several TB of disk space, hundreds of computers in farm.