Networking Essentials Chapter 12 LAN Installation and

1
Networking Essentials

• Chapter 12 LAN Installation and Operation

2
LAN Selection Criteria

• Backdrop evolution in technology and changing
  needs of users over time
• If a new LAN, form a task force made up of tech
  specialists, users and mgmt
• Task force must be aware of the companys vision
  and mission and financial condition in order to
  make informed choices

3
Figure 12-1 LAN selection criteria for
managers.
4
LAN Selection Criteria

• Requirements must be thoroughly understood and
  agreed to by all
• Decision to go ahead must be well thought out
  since it might require lots of money
• A LAN Administrator needs to be hired or selected
  and be part of the task force before any final
  decision on LAN specifics is reached

5
Figure 12-2 LAN cost considerations.
6
LAN Costs

• Short term savings may result in an undersized
  and inadequate LAN
• LAN criteria should be weighted with an eye to
  managing costs overall
• There must be a known budget commitment before
  ordering and installation begins

7
Factors Affecting LAN Performance

• Protocol
• Speed
• Load or Traffic Volume
• Error Rates
• Software Efficiency
• Speed of Servers and Disks

8
Protocol

• CSMA/CD provides good throughput on lightly
  loaded, shared segments.
• More traffic means more collision
• Think of our highways
• Above a certain threshold, collisions negatively
  affect throughput.
• Token Passing provides predictable behavior and
  scales well,
• latency increases as more stations are added to
  the ring.

9
Speed

• Clearly the backbone needs to be high speed
  (100Mbps or 1Gbps)
• Workstation requirements depend upon the
  applications being installed on the LAN
• LAN switching almost always delivers better
  performance than shared segments using Hubs

10
Load or Traffic Volume

• Delays increase as traffic continues to increase
  on a LAN
• Collisions also increase
• Delays waiting for token also increase
• LAN switching (micro segmentation) helps to
  manage the load
• Demand will normally continue to increase and
  must be monitored

11
Error Rates

• Errors require retransmissions
• Too many retransmissions add load to the LAN
  (increase traffic)
• Not usually a LAN problem more a problem for the
  WAN due to distances involved

12
Software Efficiency

• Varies from vendor to vendor
• There is a built-in pressure to be as efficient
  as possible in order to compete
• Efficiency normally increases as new releases are
  introduced.

13
Speed of Servers and Disks

• Servers can become performance bottlenecks which
  increase network delays and possibly
  retransmissions
• Servers need to have ultra fast processor or be
  multi-processor based (preferred)
• Disks need to be fast and fault tolerant
• Slow disks will increase queuing at the File
  Server which can lead to congestion

14
LAN Installation

• In house or outside firm?
• Project Plan a must level of detail varies with
  the complexity and size of the LAN under
  construction
• Hardware/Software configuration vital tasks of
  the Network Administrator
• User Training A MUST!
• Helpdesk type support A MUST!

15
LAN Management Considerations

• Organization and Management identify LAN
  Administrator(s) define local and global
  policies and ways to enforce them.
• Physical Safeguards equipment should be in a
  locked environment which is conditioned for
  equipment (temp, humidity,)
• Documentation A MUST! Topology wiring
  diagrams types, numbers and locations of
  equipment and cable runs demarc locations

16
LAN Management Considerations

• Change Control formal procedures for
  maintaining and upgrading the network must
  include user notification and mgmt approval
• Hardware/Software/User data Backup and Restore
  system with well understood policies
• Access Security not just physical goal is to
  prevent unauthorized use of network services

17
LAN Management Considerations

• Network Application Standards what type of
  applications are best for the LAN formal
  procedures for introducing new applications
• Performance monitoring essential for
  troubleshooting and capacity planning

18
LAN Client Software

• Client Software is an extension to the Client OS
  (used to be purchased separately)
• Supports various Layer 2 topologies (drivers) and
  Application Program Interfaces (APIs)
• DOS IBM space NetBIOS
• TCP/IP for multiple application use
• Client software must be compatible with Network
  Operating System (NOS) running on the Network
  Server

19
LAN Server Software (NOS)

• Provides overall control of the LAN
• Usually Layer 2 independent (supports all normal
  types)
• Used by Network Administrator to manage the LAN
  services and LAN hardware/software access

20
Novell Netware Highlights

• Originally proprietary hardware and software
• Operates over all popular Layer 2 protocols
• Internetwork Packet Exchange (IPX) Layer 3
  services
• Must configure client and server to communicate
  pre ver 6.0
• Sequenced Packet Exchange (SPX) Layer 4
  services (TCP/IP now standard)
• Browser Interface no longer requires Novell
  client software
• Services printing, file storage, directory
  services, security,

21
Microsoft Windows

• NT Server (NTS) first multitasking NOS from MS
  supporting disk mirroring
• Supports TCP/IP, IPS/SPX, NetBIOS, and AppleTalk
• Windows 2000 Server (NT based)
• Web Interface
• Cluster support
• Major upgrade to NT
• Active Directory Support

22
Microsoft Windows

• Windows 2003 Server
• .NET Support
• Sized to fit environment (4 flavors)
• Standard
• Enterprise
• Data center
• Web
• Enhanced Security
• Fault tolerance
• Console Driven network management
• IPV6 support and IPSec support

23
UNIX

• Open given away to Universities in 1970s
• Multitasking runs on all sized platforms
• Portable and backwards compatible
• Many vendor specific versions (HP, SUN)
• TCP/IP support is built-in

24
LINUX

• Free to anyone (Open Source)
• Stable and efficient version of UNIX
• Efficient in handling resources
• Many different versions to choose from
• Support can be tricky (or cost money)
• Use Linux User Groups (LUG)
• Adopted by IBM for many new hardware platforms

25
LAN Security

• Management establishes and enforces security
  policies
• Includes both Physical and Access Security
• Proxy Server useful for hiding internal addresses
  and for enforcing Internet site access
  restrictions
• Requires lots of care and feeding

26
Security Policies Procedures

• Passwords makeup, frequency of change
• Sign off when leaving policy
• Data encryption what kind
• Data backup policies
• Virus Protection
• Dial-up Access restrictions
• Software control (keep it legal)

27
Virtual Private Networks (VPNs)

• Reduces cost use the Internet as a WAN
• Increases security through tunneling
• A VPN is a private network which is transported
  on a public network
• Usually provides for some form of encapsulation,
  authentication and encryption

28
Figure 12-4 A VPN creates a private
connection of remote users over the Internet.
29
Tunneling

• Encapsulation of one packet inside of another
• Point-to-Point Tunneling (PPTP) packages data
  into PPP packets which encapsulate IP packets
  uses encryption and authentication
• Layer 2 Tunneling Protocol (L2TP) Cisco version
  of PPTP
• IPSec standard for Layer 3 Security

30
Home Networking

• Driving forces high speed access to the
  Internet wireless technology costs continue to
  come down
• Requires ease of installation, reliability,
  scalability, standards compliance
• Typically Peer to Peer based networking

31
Home Network Types

• Ethernet (PCs to hub/switch and router)
• Wireless (PCs to WAP to switch and router)
• Phone line (share existing phone line without
  interfering with voice traffic)
• Windows ICS (Internet Connection Sharing) allows
  multiple PC/s to share a common Internet
  Connection

32
Power Line Network

• Relatively new concept
• Uses power transmission lines as the network
  media
• Slower very susceptible to electrical appliance
  usage in the home

33
Case Study

• Now you decided to open a new business with 5
  employees. The business is to deliver Liquor
  sales over the internet
• Define your business vision objective
• Use pg 320, 321 and 324 checklists to upgrade
  your WIRED LAN
• Must be client server architecture and include
  server costs
• You got seed for around 6,000
• You expect sales to be 50k 1st year, 70k 2nd
  year and 100k 3rd year
• BE CREATIVE