Sleeping Bear Dunes Design, Development, and Installation of a Local Area Network

Csc 363

Due date 2/12/99

By Pauline Hinga

 

Section A: Executive Summary

Outline of the three proposed technologies

Company

Technology

Infrastructure

Network operating system. (NOS)

Lhasa Technologies

Asynchronous Transfer Mode (ATM)

  • Dual, Counter-rotating single mode backbone
  • 4 strands multimode to desktop for floors 0 & 1 connected by a physically secured concentrator.
  • Each station on floors 0 and 1 will be dual attached to the ring
  • Thicknet coaxial cable to desktop for floors 2&3
  • Data jacks for floors 2 & 3
  • 2 data jacks on floor 4
  • A router on floors 2 & 3
  • A router or concentrator in dispatch center for internet access for entire building

Lhasa technologies recommends using NT 5.0 as the Network Operating System (N0S)

Reason:

  • NOS is robust and economical management solution
  • Widely used by other local governments, hence support may be readily available
  • NT has specially built in backup and archival utilities

FastCom

Fast Ethernet

  • Logical star topology
  • Cat 5 UTP for backbone. Transmitting at 100mbps
  • 4 pairs Cat 5 to desktop for floors 0 & 1 connected via a physically secured switch
  • 2 pairs Cat 5 UTP to desktop for floors 2 & 3
  • 2 data jacks on floor 4
  • A switch or active hub on floor 2 & 3
  • Router or switch and a gateway in dispatch center for internet access for entire building

FastCom recommended NetWare 4.12 for the Network Operating System.

Justification

  • NOS widely used in other local governments
  • Its mature and robust
  • Handles access to peripheral devices
  • Has an excellent account and administration tools

Dune networks

Fiber Distributed Data Interface-based (FDDI)

  • Dual, counter Rotating single mode rings on the backbone
  • Transmitting at 100mbps
  • 1 strand multimode fiber to desktop for floors 0 & 1 connected via a physically secured concentrator
  • workstations on floors 0 and 2 are dual attached to the ring
  • 4 strands multimode fiber to conference room on floor 2
  • 4 pairs Cat 3 UTP to desktop on floors 2 & 3
  • Data Jacks on floors 2 & 3
  • Cat 2 3-based data jacks on floor 4
  • Stations on floor 2 to 4 are dual attached with no concentrator
  • Router or concentrator and a gateway in dispatch center for internet access for entire building

 

 

Dune networks recommended Novel NetWare 4.12 Network Operating system.

Justification:

  • Mature and Robust
  • Widely used by other local governments. Support by providers would be high
  • NOS handles access to peripheral devices

 

 

Sleeping Bear Dunes Functional Needs

Floors

Functonal Needs, Expections and Requirements

Floor 0 : Jail

  • Must be fully interconnected with floor (Police Department)
  • Application and file sharing
  • Each office should contain a data jack
  • Reception area with data jack or passive hubs
  • Visitor room should include 1 data jack and video conferencing capabilities

Floor 1: Police Department

  • Each office should contain a data jack
  • Individual offices will need access to outside centers (i.e. National Crime Information center)
  • Police should be able to use the video conferencing capabilities to monitor visitor room

Floor 2: Health Department

  • Each desktop should be connected to the network
  • Each desktop should have video conferencing capabilites
  • Staff should be able to share files and use specialized applications
  • Staff should be able to share resources e.g. CD-ROMs and printers
  • Need to access outside resources such as Center for Disease Control

Floor 3: City Clerk

  • Each office should be connected to share file, application as well as print servers
  • Plan on implementing a client –server in two years

Floor 4:

No specialized needs were outlined by Sleeping Bear Dunes for this floor

 

section B: Technology Overview

ATM:

Advantages

Disadvantages

FAST ETHERNET:

Advantages

Disadvantage

FDDI:

Advantages

Disadvantages

 

Section c: Analysis of the technologies proposed

 

LHASA TECHNOLOGIES:

Lhasas Technologies has proposed the implementation of an Asynchronous Transfer Mode–based LAN for the Sleeping Bear Dunes Network. The infrastructure is based on a dual counter-rotating ring using single mode fiber. One problem with single mode fiber is that it is made out of glass and is therefore very expensive. In addition, implementing single mode fiber to a dual-ring network would require running two parallel fibers. This is because single mode fiber transmits only one signal at a time. However, if cost is not an issue, single mode fiber can be an excellent medium because it provides maximum security, transmits data at extremely high data rates, and has a very high bandwidth.

Lhasa technologies also suggest running Thick Coaxial cable to the desktop of floors 2 (county Health Dept) 3 (city clerk) would not be a good idea. This is because thick Coaxial cable is hard to manipulate and pull around tight corners and bends. It should be noted however, that thicknet cable in comparison to thinnet cable carries data signals for longer distances. However, even in this case I would still suggest using thinnet as opposed to thicknet because ease of installation. Other cables that could be used to the desktop are UTP CAT 5, which would also be easy to install.

Another flaw in the Lhasa Technology recommendation is that of installing dually attached concentrators on each floor. Dual attached devices implies that they are attached to both the primary and secondary ring of the ATM. Having devices on the two rings would imply more points of failure on the network. I would suggest having all workstations and printers as single-attached devices on the network. I would suggest connecting the gateway to a router, which would provide Internet connection to the network.

Finally, Lhasa Technologies means informs its client on the version of the NOS. NT 5.0 is still on a trial bases and the version is not out yet. I would suggest using NT Client for the LAN NOS.

 

FASTCOM:

FastCom suggest installing a Fast Ethernet LAN for the sleeping Bear Dunes Network. Their proposal includes implementing a star topology using CAT 5 UTP for the LAN backbone. A star topology on the main network would not be ideal because it would provide a single point of failure on the network. If the central hub goes down the whole network would go down. My recommendation for the topology would be to use a combination of topologies. For example using a star/bus topology would decentralize and vary the points of failure. In addition one point of failure would not necessary bring the whole network down. Another option would be to implement a combination of the star and ring topology (Diagram 1). Hence, if one part of the network goes down in a star/ring topology, alternative routes would be negotiated to transmit.

Diagram 1:

 

 

 

 

 

Another Flaw that can be noted while implement FastCom proposed Network is that they do not identify what kind of connectivity device will be needed to connect floor 1 and 2 to the network. In addition, the jail needs and preference to be fully interconnected to the 1st floor have not been addressed in this proposal. My suggestion would be to connect all equipment on each floors to an active hub which would in turn be connected to the network via a router. Through the routers, the two floors would be able to communicate.

FastCom also suggest installing data jacks to the 4th floor and respond to the Sleeping Bear Dunes, Police Department need for having data jacks installed in each office. My recommendation here would be to install if any, only one data jack on the fourth floor incases of future expansion. I would recommend installing at least two data jacks on all other floors. These jacks could be shared between offices.

Although FastCom rationalizes their use of Fast Ethernet based on the high speed of the network, Fast Ethernet would not be ideal for huge graphical, voice and large data transmission. This is because Fast Ethernet operates on a shared medium that is not pre-active. Hence, all collisions on the network are detected after they have occurred using the CMSA/CD protocol. Hence, collisions on the network would imply regular interruptions. The county health department, Police and the Jail floor all require some level of desktop video conferencing. To ensure maximum through put of data to the desktop I would suggest implementing Switched Ethernet Technology. Switched Ethernet would guarantee throughput of 100mpbs data rates.

DUNE NETWORKS:

Dune networks suggest installing a FDDI based LAN network with dual counter-rotating ring on the network backbone. They also suggest running 1 strand single mode fiber to the desktop. However, it is not possible to connect to the FDDI network using 1 strand fiber. At least 2 strands of fiber would be required for communication with the network.

Dunes Network is also wrong to suggest that all workstations on floors 0 and 1 be directly attached to the both the primary and secondary rings of the FDDI backbone. The consequences of having dual–attached devices would be that in case of device failure communication on both rings would be broken, resulting in network failure

Dunes Networks also make a flaw of suggesting that all stations on floors two through 4 be single-attached devices directly on the network. They fail to recommend what interconnectivity device would be used to connect stations to the network. Stations cannot be directly attached to the FDDI backbone, because stations would be potential points of failure on the network. I would recommend using a concentrator to connect devices to the backbone. Dunes network also suggests using a router or a concentrator to attach the gateway to the network. I would suggest attaching the gateway to a router as opposed to a concentrator.

 

 

Section D: Recommendation

After analyzing all the proposed designs from the three companies above, I decided to recommend a Switched Ethernet technology with single-mode fiber backbone. Switched Ethernet is very similar to the Shared Ethernet technology suggested by FastCom. However, the critical difference between the two technologies is that Fast Ethernet is a shared technology while Switched Ethernet uses switching protocols. Shared technology implies that all devices on the network contend to send packets across the network. Before each device transmits it must ‘listen’ to make sure that no other devices are transmitting at the same time. However, in situations why packets are sent into the network at the same time, collisions occur and consequently data transfer interruption. In the case of Sleeping Bear Dunes network, they plan to use video conferencing very often as well as downloading large data from other centers. With this in mind I would recommend implementing Switched Ethernet technology which when combined with the fiber, can ensure maximum data rate capabilities. In addition, data would be received without interruption.

Secondly, I recommend running 2-strand multimode fiber to the desktop on floors 0 and 1. These two floors are at the highest risk of data "eavesdropping" because of the nature of their environment. Floor 0, which is the jail, would provide an easy target for network bridging. Likewise floor 1, which is the police station, is the main entrance to the building and houses the main lobby. For floors 2 and 3 I would recommend running UTP cat 5 because it easy to install. In addition, the building has existing UTP CAT 3 cable that would make it easy to upgrade to CAT 5 UTP.

Third, I would suggest having all stations on each floor connected to a hub, which would then be connected to a router for network connectivity. In addition, at least two data jacks should be installed on every floor with the exception of floor 4, which should probably have 1 data jack incase of future expansion.

I would recommend connecting the gateway to a router, which would provide connection between the Internet and the network. Finally, I recommend using Novell NetWare 4.12 for the Network Operating System, for the management of the LAN. NetWare is robust and mature and provides an economical management solution. NetWare also provides access to peripheral devices such as Client-severs, which will soon be introduced at the Sleeping Bear Dunes Network.