Securing Border Routers

[Brandon Kim <brandon.kim () brandontek com>]

Gents:

What measures do you take to protect your border routers? Our routers are running BGP so I'm interested 
if there is any way to secure them without interfering with BGP? Is it normal to put a firewall in front of the
border routers?

I'm concerned about DDOS attacks mainly....although we haven't had any, I don't welcome them.....

Brandon