District Network Requirements
The Washington Elementary School District is implementing an enterprise-wide network, which will include Local Area Networks at each site and a Wide Area Network to provide data connectivity between all school sites. The District wishes to provide Internet access, as well as automate many of the district's administrative and curricular functions. The network implementation must continue to be functional for a minimum of 7-10 years, and should include a minimum of 100x growth in the LAN throughput, 2x growth in the WAN core throughput, and 10x growth in the District Internet connection throughput. Only TCP/IP and Novell IPX will be allowed to be implemented on the network.

Two LANs segments will be implementd at each school and the District Office, one for Administration usage, and the other for student/curriculum usage. At each location, a Main Distribution Facility will be established as the central point for cable termination, and will also be the point of presence (POP) for the WAN connection. Each classroom requiring connection to the network will be able to support 24 workstations and be supplied with 4 data runs, with one run terminated at the teacher's workstation. A single location in each room will be designated as the wiring POP for the room. From this location, wiring will be distributed within the room via decorative wire molding.

District-supplied servers, categorized as either enterprise or workgroup services, will be placed on the network topology according to function and anticipated traffic patterns of users:

• Domain Names Service and Email Services
• Administrative Server
• Library Server
• Application Server
• Other Servers As Needed

Network security will be based on a double firewall implementation with all Internet-exposed applications residing on a public backbone network, and all connections implemented from the Internet into the district's private network refused. In addition, Access Control Lists will be implemented on all school routers to prohibit traffic from the curriculum LAN onto the administrative LAN, with the exception of applications such as email and DNS which pose no risk. A user ID and password policy will be published and strictly enforced on all computers on the network. All computers will have full access to the Internet.

All Internet connectivity will be supplied through the District Office designated as the single point of contact for all schools and organizations within the district. The connection will be hightly controlled, with bandwidth upgraded as usage dictates. ACLs will be used to protect the network from unauthorized access. Email and DNS serivces will communicate freely in both directions, since these applications pose no security threat. A web server located on the public backbone will be partitioned to allow any school to install a web home page on the Internet. No public web servers will be permitted on the internal District network.

Network User Expectations

1. Functionality
   The primary concern of most users is application availability on the network. This includes fast response time, high throughput, and network reliability.

   Response time is the time between entry of a command or keystroke and the execution of the command or delivery of a response.¹ For the users on the Desert View LAN, this primarily entails rapid response from the library and file servers, as well as reasonably fast access to the Internet.

   As an elementary school, throughput requirements on the Desert View LAN can be expected to be moderate. It is expected that throughput usage on the curriculum network will primarily involve accessing the curriculum file server, the library server, and the email server, with some web browsing also expected. Throughput on the administrative network is expected to include access to the library and email servers, the Internet, and frequent access to the administrative server.

   While reliability of all network servers and devices is important, priority is assigned to the administrative server, which will house student tracking, attendance, grading, and other administrative functions. The curriculum network users place their priority on the curriculum file server and the library server.

   In order to meet these demands, the minimum expectation for the initial LAN implementation will be 1.0 Mbps to each host computer on the network, and 100 Mbps to any server host in the network.

2. Scalability
   This network implementation is expected to be functional for a minimum of 7-10 years without significant upgrades in network equipment or rewiring of horizontal or vertical cabling. Considerations include an expected 100-fold increase in LAN throughput, a doubling of expected WAN core throughput, and an expected 10-fold increase in District Internet Connection throughput.

3. Adaptability
   The network implementation must be flexible enough to accomodate future technologies as they become available. These may include newer switching technologies, better servers, more secure firewalls, faster routers incorporating new routing protocols, etc. The network should be designed to be "modular," allowing new network equipment to be added or swapped with a minimum of network downtime.

4. Manageability
   The network implementation must facilitate network monitoring and management by the network administrators. The network must include fault-tolerance, and elements to facilitate the stability of the network and reduce unnecessary network downtime.

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