## (3) Site LAN Logical Topology (including IP Addressing Scheme)

### Logical Diagram:

NOTE: right click to zoom in

### Important Design Notes:

- The diagram above is done in "logical, block form" - (as preferred by our lecturer) - to see the more detailed "star form" logical LAN diagram click "see it all working together" (in the menu bar) and step through the animation sequence.
  - step through further to see the logical layout of (a sample) classroom.
- Extended star topology was used because IDFs were seen as necessary
- This chosen logical scheme increases simplicity

- 1 subnet (10.42.111.0) = main admin section, servers & teachers
- 2 subnets (10.42.112.0 & 10.42.113.0) = curriculum
- 1 subnet (10.42.114.0) = *spare

- 2 subnets (508 hosts) are more than enough for teachers & curriculum.
- The spare subnet will come in useful if another building is built
- VLAN scheme was essential to isolate teachers & students (since they connect to the same switches in the IDFs)
  - VLAN1 (default) = students
  - VLAN2 = teachers
  - VLAN1&2 = admin & servers……… (allowing admin access to teachers & students)
- Very short, efficient ACLs permit curriculum access to the main enterprise server, but deny them access to admin
- From the main admin section, broadcasts can be sent to all admin, teachers and/or students - (e.g. network administrator may wish to netsend important messages to all computers)
- Trunking between the switches in the MDF allows teachers to be on the same subnet as admin (10.42.111.0)
- Placing the single DNS, E-mail, Application & Library server on the "E0 switch" was a special design decision
  - Although it's the curriculum computers which require these services most frequently, we attached it to the "admin subnet" because, unless traffic between this server & curriculum passes through ACLs (allowing only certain services), it is possible for students to cause damage.
  - Also, this server is closest to the MDF.
  - Evidently we have sacrificed slighltly increased network traffic for better security.
  - Besideswhich - even if this server was placed on the E0 or E1 switch, the curriculum computers on the opposite switch would still need to traverse through the router to access it.
- The commands and possibilies for routers to handle VLAN information were not really covered in this course. We understand that it may be possible for certain routers to handle VLAN issues and perhaps even remove the need for trunking in the above diagram (allowing teachers with statically mapped addresses in the subnet 10.42.111.0 to exists on a different subnet), but for the purposes of this assignment we have left in the trunking.

### School's IP Allocation Table:

NOTE: most of this information is in the diagram above

Device | IP Address | Location
ROUTER'S INTERFACES
PRI0 to Service Center | 10.42.110.1 | in MDF
E0 to switch | 10.42.111.1 | in MDF
E1 to switch | 10.42.112.1 | in MDF
E2 to switch | 10.42.113.1 | in MDF
ATTACHED TO MDF (all in admin section)
DNS, APP, EMAIL & LIB SERVER | 10.42.111.2 | AD6
ADMIN SERVER | 10.42.111.3 | AD6
princpl | 10.42.111.6 | AD1
assnt pricpl | 10.42.111.7 | AD2
nurse | 10.42.111.8 | AD5
printer#1 | 10.42.111.9 | AD3
printer#2 | 10.42.111.10 | AD3
sectry#1 | 10.42.111.11 | AD3
sectry#2 | 10.42.111.12 | AD3
sectry#3 | 10.42.111.13 | AD4
sectry#4 | 10.42.111.14 | AD4
sectry#5 | 10.42.111.15 | AD6
ATTACHED TO IDF#A & IDF#B
teaches (of faculty #A) | 10.42.111.64 | A1
10.42.111.65 | A2
10.42.111.66 | A3 (1st)
10.42.111.67 | A3 (2nd)
10.42.111.68 | A4
10.42.111.69 | A5
10.42.111.70 | A6
10.42.111.71 | A7
10.42.111.72 | A8
10.42.111.73 | A9
teaches (of faculty #B) | 10.42.111.74 | B1
10.42.111.75 | B2
10.42.111.76 | B3
10.42.111.77 | B4
10.42.111.78 | B5
10.42.111.79 | B6
10.42.111.80 | B7
10.42.111.81 | B8
10.42.111.82 | B9
10.42.111.83 | B10
10.42.111.84 | B11
students (of faculty #A & #B) | dynamically assigned in range 10.42.112.8 - to - 10.42.112.254 (by DHCP server) | A1-A9 & B1-B11
ATTACHED TO IDF#CD
teaches (of faculty #C & #D) | 10.42.111.85 | C1
10.42.111.86 | C2
10.42.111.87 | C3
10.42.111.88 | C4
10.42.111.89 | C5
10.42.111.90 | C6
10.42.111.91 | C7
10.42.111.92 | D1
10.42.111.93 | D2
10.42.111.94 | D3
10.42.111.95 | D4
10.42.111.96 | D5
10.42.111.97 | D6
students (of faculty #CD) | dynamically assigned in range 10.42.113.8 - to - 10.42.113.254 (by DHCP server) | C1-C7 & D1-D6

### ConfigMaker:

NOTE: This diagram represents what we created in ConfigMaker, but was tidyed up for better clarity

- As requested, we made attempts to draw our LAN network in ConfigMaker, but found the following limitations:
  - ConfigMaker had very few switches & router models available
    - consequently we had to use incorrect switch & router models - with much fewer ports/interfaces than the actual
  - ConfigMaker did not allow VLAN configuration
    - the trunking (in red) was not allowed
- The diagram above has been edited - to download our actual ConfigMaker (version 2.6) file click "ConfigMaker files" (in the menu bar)