The players in the low-to-medium end of the server market include Netware 4.1, OS/2 Warp Server, NT Server 4.0, and Unixes on Intel such as ...
The players in the low-to-medium end of the server market include Netware 4.1, OS/2 Warp Server, NT Server 4.0, and Unixes on Intel such as SCO and Solaris.
Netware 4.1:
Netware 4.1:
- Netware is a very fast, effective, well-supported file server that supports OS/2, Mac and windows clients. It also includes x.500 global directory service and the tools that make it usable.
- Today over 4000 applications run on Netware including the major DBMSs. Future releases of Netware will provide c2 level security.
Netware is a poor application server. To address this problem, Novell introduced Netware Loadable Modules (NLMs) which are special namespaces set aside on the server that allow programmers to provide new system services. NLMs become the part of the Netware operating system kernel.
The problems with NLMs that make it very difficult are,
- limited memory protection
- lack of memory management
- no support for preemptive multitasking.
NT Server:
- NT Server provides the following additional features over NT Workstation: 1.File/Print server support 2. Built-in Internet server 3. Disk mirroring 4.Striping and SMP.
- NT Server code can be compiled to run on different microprocessor platforms like Intel Alpha, PowerPC and MIPS.
- NT 3.5 enhanced the TCP/IP stack, which provided better support for Netware and improved the performance.
- NT 4.0 added Network OLE support, enhanced security, multiprotocol routing and ISDN communications.
- NT is a good application, database and file/print server platform. Its tight coupling with Windows, Backoffice and Network OLE makes it a natural server in Microsoft environments.
- NT does not scale well. Its SMP engine seems to hit with four processors. Adding a fifth processor slows it down. In contrast, Unix platforms-for example, Solaris have demonstrated linear scalability up to 64 processors.
- NT does not provide a enterprise directory server. Its directory does not even integrate with other Backoffice applications.
- Only NT Workstations have passed C2 security certification. NT servers will have security holes.
- NT’s backup facilities are not as good as its competitors.
- Like NT, OS/2 is also an excellent application server for departments. It is a 32 bit operating system, that has incubated some of the leading edge software including Lotus Notes and CORBA services.
- IBM introduced OS/2 Warp Server, which combines OS/2 Warp application server environment with LAN server, a very fast file and print server.
- Warp Server provides a OOUI user interface for easy installation, configuration and system management.
- Warp Server also provides Disk Mirroring, remote administration, remote software distribution, a back up server and software metering.
- OS/2 is an Intel only platform. This Intel Only may also be a benefit. That is OS/2 does not incur any extra burden of a portability layer. It can take full advantage of Intel hardware and SMP buses and become the fastest OS for Intel Servers.
- Second shortcoming is its system limits. The largest file size it can support is 2 GB. Disk partitions are limited to 512 Gbytes.
- Many of OS/2 ‘s high end server functions are still futures and are not implemented. This includes, C2 security, Unicode support, transactional file systems and memory-mapped files.
- Unix provides a function-rich operating system that is scalable from desktop to super computer. Its close connection with universities makes it a great incubator of new ideas.
- Unix server industry grew out of the downsizing of mainframe applications. It provided a poor man’s mainframe alternative. However in the PC LAN environment, it is viewed as a rich man’s server.
- The latest highest growth area for Unix servers is the Internet. Unix standards have become Internet standards including mail, FTP, TCP/IP and domain name service.
- Unix world is also working on 64-bit standard.
- There were over 45 variants of Unix on market. Because Unix is a hardware independent operating system, an application should be able to run on any machine that supports Unix from a PC to super computer.
- Lack of binary compatibility – Unix world is different from PC world where software comes in low-cost, shrink-wrapped floppy packages that can run on any PC clone that runs MS-DOS, NT, Windows 95 or OS/2. Unlike other operating systems that are developed by one company and marketed on many types of hardware platforms, unixes vary widely. There is no broadly supported standard.
- Functional differences between Unix – There will always be differences between Unix. Vendors like to sell products and functional differences are required to avoid relentless no-win price wars.
