connect to each other by the 100Mbps Verizon TLS fiber optic lines, and the routers are interconnected by the point-to-point backup data T1s (see WAN Network). The routers are connected to the core switches by two 100 MBPS feeds.
The switches are attached to the surrounding buildings on the campus via 100Mpbs copper or fiber optic lines. The topology varies by campus: Riverhead is a ring with three buildings, Brentwood has a core node and two sub-nodes (e.g. each node acts as star for several buildings (5/7/3 buildings respectively), and the Selden campus is a giant star with 17 buildings.
The Computer Center is on the Selden campus and houses the main college router and the attached routers for SUNYNet, AT&T and Suffolk County. It also houses the server farm and mainframe. As a result, the main campus switch is located in the Computer Center. The core switch is a Cisco 6509 with 16 ports of 1000 MPBS fiber, 24 ports of 100 MPBS fiber connections and 72 ports at 10/100 MBPS. Subnet switches provide connections to the server farm and IT support staff.
Each building on a campus is connected to the campus core switch by either a 1000 MPBS fiber or a 100 MBPS fiber connection that terminates in the building's basement or primary wire closet. On the Brentwood and Riverhead campuses, the campus core switches all use 1000 MBPS fiber trunks. The Selden campus has multiple 100/1000 MBPS feeds for several buildings that have very large user counts or have high-priority traffic.
The building switch will connect directly to all users in the building (small structures), connect to wire closets on each floor (medium structures), or connect to individual server/wire closets (large buildings and academic labs). Currently, the user data ports are connected to Nortel 450-24tx switches. Academic and administrative labs are connected to the network via small routers (Cisco 800 series) that provide bandwidth limitations, simple firewall services, and IP management services (DHCP & NAT). Academic labs vary from small labs with 8 devices (computers & printers) through large multi-room centers with over 150 devices. There are three large centers on the Selden campus (ACC, Comp. Sci, & Elect. Tech.), three on the Brentwood campus (ACC, LSC, Comp. Sci.), and two on the Riverhead campus (ACC & LSC).
The College currently maintains several dedicated wireless access points for specific labs and uses. It is in the process of adding a general purpose system for students and faculty with personal laptop computers. For each campus, multiple access nodes (AC) will interconnect to a campus-based wireless network switch. The wireless switch will provide DHCP, user authentication, and access point management for browser-based services. The ACs are currently located in the Library and Student Centers with additional spaces to be added over the next few years.
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