Reporter: They will be everywhere. Snipers dotting rooftops, the coast guard patrolling waterways. Military fighter jets enforcing a no-fly zone. 13,000 security personnel blanketing the washington... See More
Reporter: They will be everywhere. Snipers dotting rooftops, the coast guard patrolling waterways. Military fighter jets enforcing a no-fly zone. 13,000 security personnel blanketing the washington mall on monday. Protecting an event this large, complex, with this many different venue, with this be in of people coming, requires a lot of coordination and a lot of organization. Reporter: All coordinating here. The multi-agency communication center overseen by the secret service at an undisclosed location. They'll monitor surveillance images and potential threats. The fbi says there are currently no credible threats for monday. The 2009 inauguration was a logistical nightmare. Hundreds of ticket holders getting stuck in the tunnel. Authorities say this time will be better. It's always such a different feel when you come down for the inauguration. There's extensive signage, there are way finders. We have social media sites that you can follow. This year there's an app for that. It picks up where you are, tells you where the viewing screens are and the nearby events, telling me, I'm right on the parade route. Along that 1.2 mile stretch of pennsylvania avenue, from the capital steps to the white house, undercover officers and s.W.A.T. Teams out in full force. Cecilia is with us now. You were telling me, they're expecting a crowd larger than the second inaugurals for presidents clinton and bush tomorrow. You say about 800,000 or so people. We crunched the numbers. One officer for every 61 people present. So a lot of law enforcement on the streets. The president will be watching from behind a bullet-proof glass viewing area. Will he get out and walk with the crowd? We saw him do it three times in 2009. The white house isn't saying officially whether I'll be out,
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