As stated by CISCO the general requirements are:
The school district is in the process of implementing an
enterprise-wide network which will include Local Area Networks (LANs) at each site
and a Wide Area Network (WAN) to provide data connectivity between all school
sites.
Access to the Internet from any site in the school district is also
an integral part of this implementation. Once the network is in place, the
school district will implement a series of servers to facilitate online
automation of all of the district's administrative and many of the curricular
functions.
Since this network implementation will have to continue to be
functional for a minimum of 7-10 years, all design considerations should
include a minimum of 100x (times) growth in the LAN throughput, 2x (times)
growth in the WAN core throughput, and 10x (times) growth in the District
Internet Connection throughput. The minimum requirement for initial
implementation design will be 1.0 Mbps to any host computer in the network and 100 Mbps to any server
host in the network. Only two OSI layer 3&4 protocols will be allowed to be
implemented in this network, they are TCP/IP and Novell IPX.
SECTION 1 - Wide Area Network
SECTION 2 - Local Area Network & Wiring Scheme
SECTION 3 - District Supplied Servers and Functions
SECTION 5 - Security
SECTION 6 - Internet Connectivity
SECTION 7 - User Counts
The Washington School District Wide Area Network (WAN) will connect
all school and administrative offices with the district office for the purpose
of delivering data. The WAN will be based on a two-layer hierarchical model.
Three (3) regional Hubs will be established at the District Office/Data Center,
Service Center and Shaw Butte Elementary School for the purpose of forming a
fast WAN core network. School locations
will be connected into the WAN core Hub locations based on proximity to the
Hub.
TCP/IP and Novell IPX will be the only networking protocols that
will be acceptable to traverse the district WAN. All other protocols will be
filtered at the individual school sites using access routers. High-end,
powerful routers will also be installed at each WAN core location. Access to
the Internet or any other outside network connections will be provided through
the District Office/Data Center through a Frame Relay WAN link. For security
purposes, no other connections will be permitted.
Two Local Area Network (LAN) segments will be implemented in each
school and the District Office. The transport speeds will be Ethernet 10BASE-T,
100BASE-TX, and 100BASE-FX. Horizontal cabling shall be Category 5 Unshielded
Twisted Pair (CAT5 UTP) and will have the capacity (be tested) to accommodate
100 Mbps. Vertical (Backbone) cabling shall be CAT5 UTP or fiber optic
multi-mode cable. The cabling infrastructure shall comply with TIA/EIA-568-A
and TIA/EIA-569 standards.
One LAN will be designated for student / curriculum usage and the
other will be designated for administration usage (see: SECURITY SECTION). The
LAN infrastructure will be based on Ethernet LAN switching. This will allow for
a migration to faster speeds (more bandwidth) to the individual computers and
between MDFs and IDFs without revamping the physical wiring scheme to
accommodate future applications.
In each location a Main Distribution Facility (MDF) room will be
established as the central point to which all LAN cabling will be terminated
and will also be the point of presence (POP) for the Wide Area Network
connection. All major electronic components for the network, such as the
routers and LAN switches, will be housed in this location. In some cases an
Intermediate Distribution Facility (IDF) room will be established, where
horizontal cabling lengths exceed TIA/EIA-568-A recommended distances or where
site conditions dictate. In such cases, the IDF will service its geographical
area and the IDF will be connected directly to the MDF in a STAR or EXTENDED
STAR topology.
Each room requiring connection to network will be able to support
24 workstations and be supplied with four (4) CAT 5 UTP runs for data, with one
run terminated at the teacher's workstation. These cable runs will be
terminated in the closest MDF or IDF. All CAT 5 UTP cable run will be tested
end-to-end for 100 Mbps bandwidth capacity. A single location in each room will
be designated as the wiring point of presence (POP) for that room. It will
consist of a lockable cabinet containing all cable terminations and electronic
components; i.e. data hubs and switches. From this location data services will
be distributed within the room via decorative wire molding. Network 1 will be
allocated for general curriculum usage and network 2 will allocated for
administrative usage.
All file servers will be categorized as Enterprise or Workgroup
type services, and then placed on the network topology according to function
and anticipated traffic patterns of users.
DOMAIN NAMES SERVICE and EMAIL SERVICES
Domain Name Services (DNS) and e-mail delivery will be implemented
in a hierarchical fashion with all services located on the master server at the
district office. Each District Hub location will contain a DNS server to
support the individual schools serviced out of that location. Each school site
will also contain a host for DNS and
e-mail services (local post office) that
will maintain a complete directory of all staff personnel and student population for that location. The school
host will be the local post office box and will store all e-mail messages. The
update DNS process will flow from the individual school server to the Hub
server and to the district server. All regional servers will have the
capability to communicate between themselves, thus building redundancy in the
system in the event that the District master server is unavailable. Should the
District master server require a partial or complete restore of data, the
ability to query any or all of the regional servers to acquire the needed
information will be provided.
ADMINISTRATIVE SERVER
The school district is moving towards a totally automated server based administration system. Each
school location will contain an
Administration server which will house the student tracking, attendance, grading and other administration functions.
This server will be running TCP/IP as its OSI layer 3&4 protocols and will
only be made available to teachers and staff.
LIBRARY SERVER
The school district is implementing an automated library
information and retrieval system, which will house an online library for
curricular research purposes. This server will be running TCP/IP as its OSI
layer 3&4 protocols and will made available to anyone at the school site.
APPLICATION SERVER
All computer applications will be housed in a central server
at each school location. As
applications such as Word processing,
Excel, PowerPoint , etc are requested by users these applications will be
retrieved from the application server. This will provide district support staff
with a easy and efficient method for upgrading applications without having to
reload new software on each computer in the district network. This server will
use TCP/IP as its OSI layer 3&4 protocols and will be made available to
anyone at the school site.
OTHER SERVERS
Any other servers implemented at the school sites will be considered departmental (workgroup) servers and
will be placed according to user group access needs. Prior to implementation of
other servers a requirements analysis must be submitted for the purpose of
determining placement of the server on the district network.
SECTION
4 - ADDRESSING AND NETWORK MANAGEMENT
A complete TCP/IP addressing and naming convention scheme for all
hosts, servers, and network interconnection devices will be developed and
administered by the District Office. The implementation of unauthorized
addresses will be prohibited. The District Addressing Scheme can be implemented
in a number of ways. Ideas you should consider are Class A, B, and C Addresses
with appropriate subnetting, Network Address Translation (NAT), and Private
Network Numbers.
All computers located on the administrative networks will have
static addresses, curriculum computers will obtain addresses by utilizing
Dynamic Host Configuration Protocol (DHCP). Each site should have a server
running DHCP and use only addresses consistent with the overall District Addressing
Scheme. A master network management host will be established at the District
Office and will have total management rights over all devices in the network.
This host will also serve as the router configuration host and maintain the
current configurations of all routers in the network. Each region location
(Hub) will house a regional network management host to support its area. The
management scheme for the data portion of the network will be based on the
Simple Network Management Protocol (SNMP) standards. All routers will be
pointed to the master Network Management host for the purpose of downloading
new or existing configurations. The District Office will maintain the super
user passwords for all network devices and configuration changes on these devices
will be authorized from the District Office: i.e., Routers and LAN
Switches.
External Threats - Internet Connectivity shall utilize a double
firewall implementation with all Internet-exposed applications residing on a
public backbone network. In this implementation all connections initiated from
the Internet into the schools private network will be refused. In the district
security model the network will be divided into three (3) logical network
classifications, Administrative, curriculum and external with secured
interconnections between them.
This model will dictate that two physical LAN infrastructures be
installed at all schools and the District Office, with one designated
administrative and the other curriculum. Every computer and file server will be
categorized according to its function and placed on the appropriate LAN
segment. At the schools, each LAN segment will have a file server. All
applications will be categorized and placed on the appropriate server. By
utilizing Access Control Lists (ACLs) on the routers, all traffic from the
curriculum LANs will be prohibited on the administration LAN. Exceptions to
this ACL can be made on an individual basis. Applications such as E-Mail and
Directory services will be allowed to pass freely since they pose no risk. A
user ID and Password Policy will be published and strictly enforced on all
computers in the District. All computers in the District network will have full
access to the Internet. All ACLs will be controlled at the district office and
exceptions to the ACLs will be reviewed prior to implementation.
All Internet connectivity will be supplied through the District
Office with the District Office being the single point of contact for all
schools and organizations within the district. This connection will be highly
controlled and capacity (bandwidth) upgraded as usage dictates. The Internet
connection will utilize double firewall implementation with a public network
(Ethernet backbone) established for services that will be exposed to the
Internet such as master E-mail, Domain Name Services (DNS) and a World Wide Web
server. All connectivity that is initiated from the Internet to the internal
District network will be protected via Access Control Lists (ACLs) on the
routers that make up the double firewall architecture. Any connectivity
initiated from the District to the Internet will be permitted to communicate
freely. E-mail and DNS services will communicate freely in both directions since
these applications poses no security threat. A Web server will be located on
the public backbone and partitioned to allow any school to install a Web home
page on the Internet. Individual Web servers that need total exposure to the
Internet will not be permitted on the internal District network. If schools
require an independent web server host, this host will be placed on the public
network backbone.
Threaded Case Study -- User Counts at each site
Elementary School District Addressing You need to assume there will be 250 computers in each school for
student/Curriculum (C) usage and 75 computers in each school for
teacher/Administration usage (A). This would be the maximum number in any given
school. Also keep in mind that at each location (indicated by a 1 on the site
drawing) the layer 1 wiring needs to be designed to accommodate up to 25
computers: 1 run for the teachers/Admin computer (A) and 3 runs for up to 24
student/Curriculum computers (C).
Washington Elementary School District Regional Hub I: One District
Office/Data Center [75 (A)] and 11 schools [250(C) & 75(A): per
school] Regional Hub II: One Service
Center [75 (A)] and 11 schools
[250(C) & 75(A): per school]
Regional Hub III: 11 schools [250(C) & 75(A): per school] and
one community school
Notes:
4 T1 data lines will provide Point-to-Point connectivitybetween
each of the three Regional Hubs
(I. Data Center - II.
Service Center - III. Shaw Butte School)
One T1data line will provide Point-to-Point connectivity from each
Regional Hub to each connected site.
One T1-speed data (Frame Relay) line will connect all sites to the Internet. This connection will
occur at the District Office/Data Center, from the firewall routers to the
Frame Relay "cloud."
One site (Community school) will access the district WAN via ISDN.
All site routers will have modem connectivity to the Data Center
and Service Center for ease of router maintenance and enforcement of district-wide
network administration policies.