(from Google Docs)
The restricted network is segregated from the campus and the Internet by a pair of Cisco ASA-5585X security appliances (firewalls). ISB-ASA-1 and ISB-ASA-2. They are configured in a "Primary/Standby" architecture where ASA-1 is considered to be the Primary during normal operations. The interfaces to the restricted network and the 'public' network are monitored for failures. Any HW failure or change in interface status on any of the monitored interfaces will result in a failover to the standby. There is no 'preempt' feature, so the standby will remain active even when the primary is healthy and will have to be manually moved back if desired "no failover active". The two ASA's share state, so most connections will survive a failover situation. Interfaces Gi0/0 (on both ASA's) are the dedicated failover links. Gi0/1's are a dedicated failover and state link.
ISB-6509-1 is the 'default originate' for the RLAN network (172.26.0.0/16) within the 'rlan' VRF. A static default route sends all traffic (destined outside of the RLAN) to the 'restricted' interface on the Active ASA. The ASA's will NAT all RLAN traffic destined off campus to a pool of addresses in the 198.82.248.0/24 subnet. RLAN traffic destined to on-campus networks (currently 128.173.0.0/16 and 198.82.0.0/16) will not be NAT'd. It is imperative that on campus servers not block the 172.26.0.0/16 networks. ISB-6509-2 contains static routes for all on-campus traffic destined to RLAN networks and off-campus traffic destined to the NAT'd pool into the 'public' interface on the ASA's. ISB-6509-2 redistributes the RLAN network into the campus default IGP.
Coming soon....Require IOS upgrades on our Catalyst 6500's to support IPv6 in the RLAN VRF. Scheduled for Nov. 23rd, 2012.
The ASA's are configured to block all traffic (ingress and egress) except as approved by the ITSO. The following network services are required to be permitted throught the firewall:
The ITSO will request additional firewall permissions through a yet to be determined procedure.