Individual Report
COMPARISON BETWEEN WINDOWS NT AND UNIX OPERATING SYSTEM
An Assignment for Operating System module,
in the University of Central England
By: Harry Sufehmi, student-id #98799231
Introduction
------------
In this report, I abandons Windows95 for a strong reason: It
is very hard to compare Unix and Windows95 fairly. Windows95
is a desktop operating system, that is, it sacrifices many
power-features in exchange for ease of use. And it's very
good at it, it even dominates desktop PCs world-wide. Unix
in reverse, is a heavy-duty operating system that mainly
targeted for utilisation at servers or high-end
workstations; although this started to change (very slowly,
though) with the emergence of Linux. No wonder their
internal structure differs greatly. Comparing this two
operating system is quite like comparing apple and chicken.
They are for different usage so the discussion would become
too broad it would be easy to lose focus, and making this
report too lengthy.
So I choose only WindowsNT and Unix, since they are targeted
to quite the same niche; server application. For WindowsNT,
I choose WindowsNT v4.0 Server edition. For Unix, I choose
RedHat Linux, the favourite flavour of Linux that just
recently got supported by Intel, Oracle, Informix, and
Netscape.
Comparisons
-----------
[1] Kernel
~~~~~~~~~~
Straight to the record, Linux is based upon monolithic
kernel architecture, while Windows NT is based upon
microkernel architecture.
These architectures have been, and I think is still, a topic
that's being debated by the operating system experts - which
one is the best?
From a designer's point of view; microkernel would be easily
voted as the best, since it's very, very modular; as
described in Andrew S. Tanenbaum's famous book. The kernel
itself would be very tiny, it's would be just enough to
handle communications between client (a user process)
requesting a service from a server process (such as memory
manager, file service, etc). This makes it very easy to
implement or add/remove features - simply load/unload the
needed feature.
Also this makes it easy to implement a distributed system. A
client doesn't have to know where the server process is,
it'd just make a system call and the kernel handle the rest.
So the server process could actually located in a computer
4,000 miles away, and still able to serve the clients. And
more.
Due to these superior capabilities, Tanenbaum touts it
highly as the design of the future operating systems. He
even named monolithic kernel design as "The Big Mess". So
it's quite a blow when Linus (creator of Linux) choose
monolithic kernel design for his operating system. The
famous flame war goes in the Internet between Linus and
Tanenbaum. But Linus presented very good arguments,
including speed and, surprisingly, simplicity. And it comes
true, Linux is now recognised as one of the fastest
performing operating system on the earth.
How about WindowsNT? To put it simple, it promises too much,
and delivers too little. Even though it utilises microkernel
architecture, strangely:
(a) It's nowhere fast:
e.g. Linux on 486 outperforms WindowsNT on Pentium
for use as a mailserver.
(b) It's not distributable:
no NFS, no remote login/administration, etc
(c) It's not a bit modular:
Adding even just another network protocol will
require a reboot - devastating for a server that
must be running 24x7.
[2] Networking
~~~~~~~~~~~~~~
A quick glance:
Linux:
TCP/IP, IPv6, NFS, SMB, IPX/SPX, AppleTalk,
NCP (NetWare Core Protocol), plus many other protocols
WindowsNT:
SMB, IPX/SPX, TCP/IP, AppleTalk, plus many other protocols.
We can see easily that Windows NT doesn't support:
(a) IPv6:
The limitation of IPv4 have been acknowledged by
international standard bodies,
and resulted in the specification of IPv6.
Unix-world immediately embrace this new
standard - giving 2.81x10(14) combination of IP
addresses instead of just 4,294,967,296 from IPv4,
and also more subnets to be allocated.
(b) NFS:
Stands for Network File System, a recognised
standard for years for distributed computing.
The non-existence of this protocol in WindowsNT
means user must buy a separate package from
third-party vendor if they need this standard protocol.
(c) NCP
Linux brought the NCP implementation one step further,
by enabling itself to emulate a NetWare server.
Also, the newest information from John C. Dvorak's column in
PC Magazine reveals Gigabit vendors' complain, that at most
WindowsNT could only pump 400 Mbps throughput on the Gigabit
Ethernet network. And that's only after much tweaking.
Other OS such as NetWare or Unix finds no difficulty in it.
[3] System Management
~~~~~~~~~~~~~~~~~~~~~
Linux gives a lot of it; you can telnet and rlogin, which
equals as if you're using the actual computer even when
you're actually somewhere else. It's very essential if
you're administering a server farm or geographically-
dispersed servers. All configuration files is stored in
plain ASCII format, protected by security scheme so only
authorised person would be able to access it.
The only problem perhaps is lack of automatic new hardware
detection.
WindowsNT on the other hand, lack of any sophisticated built-
in remote management capability. The closest thing to it is
perhaps some tools that would enable sysadmin to view event
log, administering users, domain. If somebody needs anything
more, they must buy from the third-party vendors. Plug-and-
play support in WindowsNT is present but incomplete,
resulting in a lot of horrendous re-configuring sessions.
(update: now Microsoft has released Service Pack 4 that gives
remote admin capability via Web, but how robust this solution
is still in question)
And one of the potential problem maker is its configuration
file; it's stored in a storage named "registry" in binary
format. If it gets corrupt, you'll have to reconfigure from
all over again instead of just fixing the corrupted
configuration only (as usually done in Unix).
A client even lost US$ 10 million due to corruption of
registry files in its 10,000 NT workstations, resulting in
12 hours downtime. The backup could not be restored because
it insist on being restored in a system with exactly the
same registry files when it was backed-up (for security
purpose?).
[4] Reliability
~~~~~~~~~~~~~~~
The easiest way to measure a server's reliability is from
its uptime.
For Linux servers, it's usual for the uptime to be measured
in years.
For NT, it's usually in days.
In fact, some vendors recommends its clients to reboot their
NT servers every week, to get rid of the random junk that
running the system has left over.
[5] Scalability
~~~~~~~~~~~~~~~
Linux was not known for its scalability, but now it has
start to. The new kernel built recognise multiprocessor
system, and will utilise it. Clustering in parallel-
processing environment is achieved up to very extreme
performance, with Beowulf. Started as a NASA project, a
Beowulf cluster consist of a computer acting as a server
node and many other computer as client nodes. An example of
Beowulf system consisted of 24-nodes priced at US$ 54,000,
and its performance rivals those supercomputers which priced
at US$ 10 million to US$ 30 million range.
Still, Linux lacks other Unix's OS like Sun Solaris that
offers automatic fails-over capability (a backup server
automatically serves the network when the primary server
goes down), transparent clustering, etc.
The only scalability that NT offers is multiprocessor
capability; and that's limited to just 32 processors, small
compared to Sun Solaris' ability to utilise 128 processors.
Automatic fail-over capability could only be achieved by
using Vinca's Standby-server software. Clustering capability
is still in development, code-named Wolfpack.
[6] Security/User management
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Linux utilise standard Unix security features that has been
known and tested for years.
WindowsNT in contrast, is making its own. Its domain system
is too awkward to be used compared to Unix's or NetWare's
excellent NDS. Its C2 security that Microsoft so highly
proud of was proved to be not so good at all. Its NTFS
filesystem could be read from DOS or Linux, nullifying any
of its built-in security feature. A system with freshly
installed WindowsNT is so highly vulnerable, a lot of
program is available in the Internet for free to steal its
passwords or to become administrator in the WindowsNT box.
Also the main problem with WindowsNT is Microsoft's
reluctance to acknowledge a newly found security breach and
fix it. After much criticism, the situation is becoming a
bit better. But it's still nothing compared to Linux - a fix
could be available as soon as 2 hours after the initial
security breach's announcement.
Conclusions
-----------
After personally researching and using both of the operating
system, I can easily say that indeed WindowsNT still has
along way to go to match the capability of Unix-family
operating system.
As a desktop or departmental operating system, WindowsNT
could be the right choice for it gives consistent look-and-
feel and a lot of application software to choose from. But
for a 250 users (or more) environment, WindowsNT is a
headache for the System Administrator for lack of features,
reliability, scalability, and security.
References List
---------------
1. Digital, Inc (1997),
AIX 4.3 Leaps To 64-Bits In Dead Heat With Digital UNIX 4.0,
http://www.unix.digital.com/unix/v4/dhbrown/AIX43.htm
2. Kirch, John (1998),
Microsoft Windows NT Server 4.0 versus UNIX,
http://kirch.net/unix-nt.html
3. Bach, Maurice J. (1986),
The Design Of The Unix Operating System,
New Jersey, Prentice-Hall.
4. Tanenbaum, Andrew S. (1987),
Operating Systems - Design and Implementation,
New Jersey, Prentice-Hall
5. Rachel Polanskis (1998), Massive NT failure!,
http://tacyon.spectrum.com.au/mail/slug/msg01137.html
6. Rogier Wolff (1998),
Unix vs NT,
http://www.bitwizard.nl/unixnt.html, BitWizard
7. InfoWorld (1998),
Probing into C2 security claims: Is NT as secure as Microsoft has said it is?,
http://www.infoworld.com/cgi-bin/displayNew.pl?/petrel/980713np.htm
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Last revision: 21 November 1998