CHAPTER 4
NETWORK OPERATING SYSTEMS
Network Operating System: (p 174)
Just as a computer cannot operate without a computer operating system, a network of computers
cannot operate without a network operating system. Without a network operating system of some
kind, individual computers cannot share resources, and other users cannot make use of those
resources. Network Operating Systems must be able to allow: add-ons, support multiprocessors,
support legacy clients, should be easy to use multi-tasking, and interoperable, or be able to talk with
other computers. Novell has an edge, by adding their operating system to the hardware at the time of
purchase.
Multi-tasking:
A Multi-tasking operating system provides the means for a computer to process more than one
task at a time. Usually, you need a devoted processor to have a truly multi-tasked system. Microsoft
says their system multi-tasks, but in reality it does not.
1. Preemptive – the operating system takes control of the processor, without the task’s
cooperation. Or as I call it Reverse Priority, say if you are at Butcher Shop and you
take a number, instead of being served in an ascending order, the higher the number, the
higher the priority. There is something called multi-threaded, which there are
several processes going on at the same time, for example, this program, I am
typing, calling on the Menu Bar, Printing and saving etc.
2. Nonpreemptive (cooperative) Must wait till the CPU is idle, GPF, general protection
fault.
Software Components
For Computer Operating Systems that do not include networking functions, network
client software must be installed on top of the existing operating system. Two types of
network software are client and server.
Client Software
On a Client Software Network, a redirector processes the forwarding requests. Another
name for a redirector is a shell. The redirector is unique for each Network Operating
system you work on. Some redirectors are not compatible with other software.
To further expand, the redirector is a small section of code in the NOS. It grabs the
request in the computer, and determines if the request should continue in the local
computer’s bus, or be sent over the network to another server.
A redirector intercepts requests in the computer and determines if the requests should
continue in the local computers bus or be sent over the network to another server.
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Drive
Mapping
Drive Mapping is very useful, it is the letter name given to your Hard Drive, and it allows the operating
system to be able to identify and locate it.
EXERCISE IN CLASS:
1. Right click on Network Neighborhood
2. Select Map Network Drive
3. Limited to the alphabet
UNC Universal Naming Convention (you can tell by double backslash \\)
\\server name\share name
tick off reconnect at login
Click on MY COMPUTER, and you can now see
EXERCISE IN CLASS:
Get to the DOS Prompt
1. Type net^use^z:^\\instructor9\extras
|
Here are four ways to Map a Drive: 1. Right click on Start/Explore/Tools 2. Click on Start/Programs/MS-Dos Prompt/at C:> type net^use^z:^\\instructor9\extras 3. Right Click Network Neighborhood 4. Right Click on My Computer |
Peripherals
Redirectors send requests to peripherals as well as to shared directories. They take the Requests
from the client and prints on the printer.
Server Software
With server software, users at other machines, the client computers, can share the server’s data
and peripherals such as printers, plotters, and directories. Most Network Operating Systems not
only allow sharing, but determine the level of sharing.
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Managing Users
Has the capability to Create/Delete/Group Users, manage the network, multi-task, and monitor
and manage the resources.
Chose Network Operating System
First of all you must determine the type of Network Architecture meets your needs, is
security an issue, then server-based should be the choice.
Novell was in the market for networks for 12 years, when Microsoft entered the market. Novell had a
sloppy type of licensing. You had to buy the rights in blocks of 50, no matter on the number of new users
For example, if you only added 2 users, you had to buy the rights for 50 users. Companies hated this
about Novell.
Microsoft knows how to market, kept competing with Novell, in regards to the licensing
And Microsoft, ended up with a 1 for one, while Novell still have 25 for 1.
In 1995, Novell had 92% of the Market, not they only have 39% of the Networking Market.
Combining
Operating Systems:
Do not combine cheap cards etc. in computers, you will have compatability problems. Companies
want reliable hardware and software, not untested applications, they also want service, so
stick with stable companies such as IBM and Compaq.
Novell
Operating Systems:
Netware is Novells most popular operating system. Novell also offers client software that is designed
to run on top of other operating systems. The client operating system runs on a variety of client
operating systems. The server application can be access by client users from computers running
MS-DOS, Mircrosoft Windows (ver 3.95, 98 and win NT)
Netware is often the NOS of choice in mixed operating-system environments. If the system is
small, too expensive.
Novell Directory Services
Provides name services as well as security, routing, messaging, management, Web publishing, and
file and print services. Provides a single-point logon for the user with it a user can log on to any
server on the network and have access to all their usual rights and privileges.
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Novells Netware Services
All users on this type of system can take full advantage of the resources available.
File Services
Users and administrators alike and view the network resources once logged on.
Security
Netware provides extensive security including:
· Logon Security -- provides authentication verification based on user name
· Trustee Rights – Controls which directories you can access.
· Directory and file attributes – identifies if you can edit, read only, delete files etc.
Printing Services
Any Print request is sent directly to the server to handle, it is transparent to the user.
These Servers can support up to 256 printers.
Microsoft Operating System
Windows NT combines the computer and network operating system in one. It has a standardized
interface. Window NT operates on a domain model. A domain is a collection of computers that
share a common database and security policy. Each domain has a unique name. With each domain,
one server must be designated as the Primary Domain Controller (PDC). There is also a BDC or
Back-up Domain Controller.
SAM Security Accounts Master, max size is 40 MG, once hits 40 must make a separate domain.
There are four different domain models to choose from:
1. Single domain – single server maintains security
2. Single master – may have several domains, but one is the master
3. Multiple Master – Several domains, several large servers
4. Complete-Trust – several domains, no single domain is designated as the master,
All domains completely trust each other.
WINDOWS NT
SERVICES
File Service
There are 2 approaches to sharing files on Window NT Network. They are:
1. Share the files as on a simple Peer-to-Peer Network. The attbributes are set to
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(No Access, Read, Change, or Full Control)
2. The next level of sharing files takes full advantage of Windows NT’s Security features.
3. You can assign directory-level and file-level permissions. This allows
you to restrict privileges to certain groups.
FAT 32
This is the logical way to store data on a hard drive. Microsoft Windows 2000 can
handle FAT32. Windows NT is not compatible with 32-bit FAT. If you install Windows
NT on a 32-BIT system, it will not recognize any files existing on the 32-bit FAT
Partition. Windows 95, Ver C, and Windows 98 use a 32-bit file allocation table (FAT)
File system.
NTFS (p188)
NTFS was built for security. There is no access to the system until you logon, and
use your password. NTFS is unique to Microsofts Windows NT. It is not necessary to
have individual file security. They have a shared work group called everyone
in NT, you can get full control, but not too secure for the system.
FAT File system FAT or Fat16 has a 8.3 max for file names
VFAT can accommodate long file names, up to 256 characters.
Print Server (p 188)
Need a large hard drive to accommodate printing, some jobs can be very large, and
Must use the print queue.
Network Services (p189)
1. Messenger Service – Monitors the Network, pop-up messages
2. Alerter Service – Warns you.
3. Browser Service – Lists the servers available on domains and workgroups
4. Workstation –redirectors
5. Server Service – Controls Network Access
Interoperability
The NWLink network protocol is designed to make Windows NT compatible with
NetWare. They are:
GSNW – Provides a gateway connection between a Windows NT domain and a
NetWare Server.
CSNW –NT workstation can access files.
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FPNW – This utility manages the Print Server
DSMN -- An Add-on Utility integrates Windows NT and NetWare user group account information.
Migration Tool for Netware – Novell gets what you do not want – Kill Novell and go to NT at
Microsoft.
OTHER OPERATING SYSTEMS
AppleTalk Network
Operating Systems
An AppleTalk Network operating system is transparently integrated into the operating system of
every computer running the MacIntosh OS. It supports high-speed, peer-to-peer networking. They
call their workgroup their zone, which is unique to Apple. But they developed Phase 1 and 2, and they
were stupid in their design, that they made their own operating system upgrades inoperable
(unable to communicate), Ha, Ha.
MacIntosh came up with some rather unique creations from the firewire, used for digital cameras,
to skuzzy, which is used on large mainframe type servers.
Unix (p 192)
Unix is a general purpose, multitasking, multiuser operating system. Two popular versions are
Linux and Sun Microsystem’s Solaris, Red Hat. Unix is highly adapdable to the client/server
Environment. It can be transformed into a file server by installing file-server software. Unix was
developed by Bell Telephone and AT & T. Network able,
ready to go,
but very expensive. Unix hold onto the
source code, not
adaptable with DOS, Windows NT, but not with Apple so well. NOS not easy to use.
Banyan (Vines)
Another networking system is the Banyan Virtual Integrated Network Services. It has built-in
E-Mail Services, Directory Services, or street-talk, only can have 4 processors, which does not
make sense, very limited. Uses TCP/IP server-to-server software, exclusively.
Peer-to-Peer LANS
(p 193)
In many offices and small businesses, there is a need for a simple peer-to-peer network. Most of
the popular operating systems include the necessary software to configure a peer-to-peer network.
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Windows for
Workgroup (Ver
3.1)
This operating system is used in an area of UFT, and it is prone to break-downs. Not a great
security set-up. Security is local to each machine, either full control, read only, or password control.
Windows 95 &
98
Windows 95
and 98 operating systems include software necessary to create a peer-to-peer
network
and enable sharing of printers and files. Note: that users of Windows 95 and 98 cannot have the full
benefit of Windows NT security features; those features require use of the NTFS file format which
is not compatible with Windows 95 or 98.
Warp Connect
This is a peer-to-peer, shares applications and printers. Not on the market long.
Network Operating Systems in Multivendor
Environments
Most networks today exist in mulitvendor environments. While such networks can pose challenges,
they work well when properly planned and implemented. These systems can be very complex, take
for example
General Motors, with their series of LAN’s connected, between
States. Major problems can arise when the company is running several mulitvendor applications.
Multivendor Solutions
Ensuring interoperability in multivendor environments can be carried out at either the server end
(also referred to as the “back end”) or the client end (also referred to as the “front end”) The choice
you make depends on the vendors you are using.
The Key to running a multivendor system, is by using redirectors. Each redirector handles only
the packets sent in the language or protocol that it can understand. The redirector can forward the
information to the proper destination. Microsoft has built-in redirectors.
Thin/Client –Works at the server end, all processors are at the server end
Fat/Client – in the P.C. client end.
Vendor Options
There are three major networking product vendors: Microsoft, Novell and Apple
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Microsoft
Microsoft has a built-in redirector that recognizes Microsoft networks into the following operating systems:
Windows NT
Windows 95 & 98
Windows for Workgroups
The redirectors are automatically implemented during the operating systems installation.
Protocol
Ensure that the operating systems are communicating with the same languages, therefore the same
rules and standards. You will find that TCP/IP is used a lot, and it is necessary if you want to get
onto the Internet. NetBeui is for small peer-to-peer Networks, it is great because there is very little
to setting up or configuring the Network. But, be sure to know that Net Beui cannot access the
Internet, so it will have some limitations. It can be good in a small company where you do not want
to provide this service, and do not want to install a fire wall etc.
Microsoft in a Novell Environment
Microsoft and Novell products are interoperable. Interoperable, or compatible, the ability of components
in one system to work with components in other systems.
MS-DOS-Based Clients
Server operating system vendors offer utilities that allow MS-DOS based clients to access servers
from the three vendors.
CLASSROOM EXERCISES:
Network
Neighborhood/(r click) Properties/Identities
The User Name must be unique, but the Group Name must be the Same
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TCP/IP
Properties: uses 4 ockteks
or sections
These are the settings on our TCP/IP card. We use class C in class or 192-223
The Information needs to have the subnet mask. The defaults are actually burned into the
Hardware cards. The range of numbers is 0-255. Network Solutions is the Company in the States that
handles IP addresses. The first ocktek shows the class range number. Why do
so many people use the TCP/IP, because it if FREE, owned by the Government.
Class A
1-127
2-24th = 16.7Million
hosts on my
network
|
255 default |
0 |
0 |
0 |
Class B
128-191
2-16th = 65,000 hosts
on my network
|
255 default |
255 default |
0 |
0 |
Class C
192-223
2-8th = 256 hosts
on my network
|
255 default |
255 default |
255 default |
0 optional 1-254 |
For TCP/IP to work you need a valid IP Address and a valid Subnet Mask. You can view
this at the
Command Prompt by typing C:>ipconfig
Another command at the Command Prompt is C:> winipcfg
EXERCISE
Right Click on My Computer/Properties/select Auto choose address, then reboot to submit
changes. Once Logged on again, go into Dos command and type C:>winipcfg and the address
169.254.225.222 (level B) comes up. The Microsoft Windows Program issues them Auto IP
addresses from the server.
Subnet Mask
What is its purpose? The Subnet Mask wants to know what Network you are on, it then compares
the Network destination with the local or remote. If the destination is the local network, it sends off
the data, but if it is not found, it searches outside the LAN.
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Router
A router is simply a software device that builds a table and finds the end destination.
EXERCISE
Purpose: This command
connections, and cable addresses are correct. It in essence checks out all your data high-ways. This
is a great tool for Trouble-shooting.
1. Command prompt:>ipconfig/all|more
2. >winipcfg
3. adapter address = mac address
4. ping C:>ping^127.0.0.1
5. C:>ping^192.168.2.4 (my terminal)
6. C:>ping^192.168.2.2 (Rajas Terminal)
7. C:>ping^101.12.1.1 (timed out)
Only talk to internal network, looking for a gateway, says address N/A
8. C:>ping^192.168.2.200 (gateway, default)
9. Remote Host
PING Connectivity Guidelines and order:
1. Ping the Local Host, or the Instructor9, this will ensure that the TCIP is configured
Properly. (address 127.0.0.1)
2. Ping Your own computer, this will test the NIC card.
3. Ping another user on the LAN, this ensures the cables are working.
4. Ping Default Gateway
5. Ping Remote Host
LAZY Mans
that all others 1-4 pings have to work, if not you would not be able to ping your
Remote
host. You can also