Treaded Case Study Computer Networks 2002 Daire Sheriden Ronan Monaghan Mark Gilmore
TCS Overview • Local Area Networks (LANs) at each site • Wide Area Network (WAN) to provide data connectivity between all school sites. • Access to the Internet from any site in the school district is an integral part of this implementation. • 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.
Layer 1 design • The school has been divided into 4 catchment areas served by 1 MDF and 3 IDF’s. • All HCC is cat 5 UTP 100Mbps cable. • All backbone cable is multi-modefibre optic cable. • The following is a design of the fibre backbone of the network. • Followed by the HCC diagrams the MDF and three IDF’s.
IDF1 IDF2 IDF3 MDF
CLASSROOM WIRING CLOSET • Equipment • 3 * 12 port standard switches • Multi-Port Patch Panel
CLASSROOM • Three standard 12 port Switches • One 32 Port Patch Panel is hard wired to the 25 Drop Points in Each Classroom • Students use ports 1 – 24 on the patch panel. • Ports 1-8 will be connected with patch leads to switch 1, 9-16 to switch 2, 17 – 24 to switch 3 • Lecturer drop-point is hard wired to port 32 on the patch panel • The 4th Cable run (Lecturer Run) is plugged into port 32 of the Patch Panel • Each Classroom Wiring Closet is placed in an elevated position and securely locked.
IDF1 WIRINGCLOSET • Equipment • Admin Server • UPS • 24 Port Enterprise Switch • Multi-Port Patch Panel • Keyboard / Mouse Shelf • Monitor
IDF 1 • IDF 1’s catchments area is the Administration Block. • This IDF must be able to service 6 offices with 4 runs going to each. • We have decided to use one 24 port switch as not all runs going into the offices will be used. • This in turn will allow for any installation of extra network devices. • An Administrative Server is contained within this IDF. The server is connected to the switch by fibre optic cable. The Administration server which will house the student tracking, attendance, grading and other administration functions • The Wiring Closet also contains a UPS to allow uninterrupted service and it also provides Power Conditioning • Every 4th port is assigned to VLAN 1 every other port is VLAN 2
IDF2 WIRING CLOSET • Equipment • 2 * 24 Port Enterprise Switch • Multi-Port Patch Panels
IDF 2 • IDF 2’2 catchments area includes 22 classrooms with 4 cat 5 runs going to each. • We have used two 48 port switches. • This will provide us with 96 ports in total. 88 of which will be used for the cat 5 runs. • The top switch is connected to the fibre backbone. This switch in turn is linked to the switch below by fibre optic cabling. • Every 4th port is assigned to VLAN 1 every other port is VLAN 2
IDF3 WIRING CLOSET • Equipment • 24 Port Enterprise Switch • Multi-Port Patch Panel
IDF 3 • IDF 3’S catchments area includes 11 classrooms with 4 runs going to each. This gives us a total of 44 runs • IDF 3 contains one 48 port enterprise switch • Every 4th port is assigned to VLAN 1 every other port is VLAN 2
MDF Wiring Closet • Equipment • One 48 port Enterprise Switch • Multi-port Patch Panel • Servers • 2 Monitors • 2 UPS • One 12 port fibre Switch • Multi-port fibre Patch Panel • Router 3640 with Serial port, Ehternet port and Dial-in Facilities. • File Servers
M.D.F. • The MDF catchments area contains 11 rooms with 4 cat 5 runs going to each. • This will mean 44 runs going out plus the IDF’s cabling. • The fibre from the 48 port switch, the IDF’s and the 7 server’s all go into the 12 port fibre switch. • The 12 port fibre switch has added RJ45 connection port to allow it to be connected to the Router • The 5 servers located in the MDF are • DHCP, Library, File Server, Application, E-mail Server • A firewall is included on the router which provides one level of security • The ACLs offer second level of security
IP ADDRESSING Our IP Addresses will be issued by the DHCP server located in the MDF. The DHCP server will be configured to allocated specific addresses to specific machines. We will be using a Class B address which will provide us with plenty of addresses for future expansion
VLANS We will incorporate 2 VLANS One for Lecturers and Staff (VLAN 1) One for Students (VLAN 2) The VLANS are implemented on the Enterprise Switches located in the 3 IDF’s and the MDF The VLANS will employ a static port , which will assign ports on the switch to a particular VLAN All Network devices under IDF1 (Admin Block) will be on VLAN 1 (Lecturers + Staff) Also assigned to this VLAN will be every 4th port on the other switches (This will be the lecturers cat 5 run from each classroom) The other ports on each switch will be assigned to the student VLAN
NAT (Network Address Translation) • IP Address space is limited and obtaining a large block of registered addresses is difficult. • For this reason we are using a private IP addressing scheme internally • Hosts cannot access registered networks such as the internet, when assigned private IP addresses. • NAT replaces the source address with a routable address and enables private addressed hosts to access registered networks without requiring globally unique IP addresses on end hosts.
ACCESS CONTROL LISTS • Access Control Lists (ACL) are used to segregate the VLAN traffic between VLAN 1 (Admin + Lecturer) and VLAN 2 (Student) and traffic coming into and out of the network • Students are not permitted access to VLAN 1. • Except for access to various file servers. • Lecturers and Admin Staff are permitted access to VLAN 2 • This ACL will allow DHCP requests and E-mail traffic between VLANs • The ACL for the VLAN traffic will be applied to the Trunking port on the router • All Hosts on both VLANs will be allowed access to the internet and E-mail. • Telnet access is denied to all hosts except from a specific Network Administrator Computer. • All external Telnet requests are denied.
FRAME RELAY • Frame Relay will connect site to the District Office • The internet connection will be at the District office. • Each site is assigned a DLCI number. • Our router serial port (s0) is connected to a CSU DSU by means of a serial cable. • The DTE end is attached to the router and the DCE end is attached to the CSU DSU
Conclusion • Objectives • Connectivity • Internet Access • Room For Expanision • Security