GLEN COVE COMPUTING NEWS

Volume 1, Issue 10

Welcome to the August Issue of Glen Cove Computing News. This month's feature article DNS: Dichard Nilhouse Sixon? will provide you with the real definition for DNS. In this tenth issue of Glen Cove Computing News you'll also find:

DNS Resources
Glossary of Terms
GCC Tech Tips
Internet Site of the Month
Cartoon of the Month
Intranet Technology of the Month

DNS: Dichard Nilhouse Sixon?

What is DNS? No it doesn't stand for Dichard Nilhouse Sixon. "The Domain Name System (DNS) is a hierarchical, distributed method of organizing the name space of the Internet. The DNS administratively groups hosts into a hierarchy of authority that allows addressing and other information to be widely distributed and maintained. A big advantage to the DNS is that using it eliminates dependence on a centrally-maintained file that maps host names to addresses."

Well that's the InterNIC definition of DNS. Let me attempt to translate that highly technical definition into somewhat plain english. DNS is a set of databases containing IP addresses and their corresponding host name. The databases are stored on systems running DNS servers, usually Unix machines running some variation of the Berkeley Internet Name Domain (BIND) software. Each host name is mapped to a particular IP address and DNS performs the translation back and forth between host names and IP addresses.

DNS allows users to invoke an easy-to-remember name (www.glencove.com) instead of a more mysterious string of numbers (206.86.190.129) when accessing a site. What if each site on the Internet was identified solely by its numeric IP address. Would you be able to remember the IP address of each site? Take for example the CNN web site. Is it be easier to remember www.cnn.com or the ip address of the site which is 192.221.50.6? DNS helps both users and administrators locate sites with greater ease.

Until recently DNS servers were almost always run on a Unix machine. Unix is the original platform for DNS software and is still generally the choice for large production name servers on the Internet. Of course this has caused numerous problems for the majority of the world's population who aren't Unix literate. Luckily a number of companies have succeeded in porting BIND from Unix to other platforms including Windows NT, VMS, MacOS, and even DOS. In addition other DNS server packages not based on BIND have been developed on multiple platforms. One of the best commercial packages I have found is DNS 2.0 from MetaInfo.

I recently was asked to install a DNS server for a client who had an enterprise network. The client was using host files in place of DNS to match IP addresses to host name. This was becoming an administrative nightmare for the client, as they were constantly have to upgrade the host files on each of their Windows NT servers. They were looking for a central database for storing their host names and IP addresses. In other words they needed a DNS server. Since they wanted to use Windows NT I first looked at the DNS server that comes with the Windows NT resource kit, but found it to be a sub-standard product. I then happened to read a review of MetaInfo's DNS 2.0 in Windows Sources where it was given a stellar rating. That was enough to make me download an evaluation copy of DNS 2.0 and install it on a test server.

It took me 30-45 minutes to setup DNS 2.0 on a Windows NT 3.51 server. The installation and configuration of DNS 2.0 is extremely straight forward and is done using your browser and two control panel applets. We're still in the process of testing DNS 2.0, but so far it's been a great success. If you're a Unix guru and can install and configure a Unix DNS server in your sleep this is not the product for you. For the rest of you who are looking for a fast and easy way to set up a Windows NT DNS server, download a 30 day evaluation copy of DNS 2.0 from the MetaInfo web site and test it out. Then let me know what you think of DNS 2.0 by sending me a message at tmartini@glencove.com.

Thanks to Brian Jenkins for providing the title of this article. Brian, who is not a computer nerd, also came up with these definitions for the DNS acronym:

Dionysus Network Server
Did Not Send
Did Not Save
Dead Network Server
Digital Network Server
Direct News Service
Deliverable Network System
Dead Novell Software

And now here's one of my infamous "deer caught in the headlight" pictures of Brian. Sort of looks like a poster boy for America's Most Wanted eh?

DNS Resources

DNS Resources Directory

RFC-1034: Domain Names - Concepts And Facilities: Warning extremely boring technical description of DNS. Pocket protector required.

RFC-1035: Domain Names - Implementation And Specification: Warning extremely boring technical description of DNS. Pocket protector required.

Setting up a basic DNS server for a domain

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Glossary of Terms

Berkeley Internet Name Domain (BIND): Implementation of a DNS server developed and distributed by the University of California at Berkeley. Many Internet hosts run BIND, and it is the ancestor of many commercial BIND implementations.
DNS (Domain Name System): A general-purpose distributed, replicated, data query service chiefly used on the Internet for translating hostnames into Internet addresses. Also, the style of hostname used on the Internet (though such a name is properly called a fully qualified domain name). DNS can be configured to use a sequence of name servers, based on the domains in the name being looked for, until a match is found. The Domain Name System refers to both the way of naming hosts and the servers and clients that administer that information across the Internet.
Internet Control Message Protocol (ICMP): ICMP is an extension to the Internet Protocol (IP). It allows for the generation of error messages, test packets and informational messages related to IP. It is defined in STD 5, RFC 792.
InterNIC: Internet Network Information Center. In cooperation with the Internet community, the National Science Foundation developed and released in the Spring of 1992 a solicitation for one or more Network Information Service (NIS) Managers to provide and/or coordinate services for the NSFNet community. Three organisations were selected to receive cooperative agreements in the areas of Information Services, Directory and Database Services, and Registration Services. Together these three awards constitute the InterNIC. General Atomics provides information services, AT&T provides directory and database services, and Network Solutions, Inc. (NSI) provides registration services.
IP (Internet Protocol) Address: The 32-bit host address defined by the Internet Protocol in STD 5, RFC 791. It is usually represented in dotted decimal notation. The Internet address is usually expressed in dot notation, e.g. 128.121.4.5. The address can be split into a network number (or network address) and a host number unique to each host on the network and sometimes also a subnet address. The way the address is split depends on its "class", A, B or C as determined by the high address bits:
- Class A - high bit 0, 7 bit network number, 24 bit host number. n1.a.a.a 0 <= n1 <= 127
- Class B - high 2 bits 10, 14 bit network number, 16 bit host number. n1.n2.a.a 128 <= n1 <= 191
- Class C - high 3 bits 110, 21 bit network number, 8 bit host number. n1.n2.n3.a 192 <= n1 <= 223

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GCC Tech Tips

Some people prefer the two-pane look of the Explorer, which is a much more informative view of My Computer's resources than the bland Folder View. To make the My Computer icon default to Explorer View, rather than Folder View edit the Registry entry for My Computer. Warning: Only attempt this if you are comfortable using the Registry Editor. You can cause major damage to the Registry if you don't know what you are doing.
1. Run regedit.exe, choose Hkey_Local_Machine\Software\CLASSES\Clsid\{20D04FE0- 3AEA-1069-A2D8-080022B30309D}\Shell\ and select [highlight] the Shell key. Right-click the right-hand pane; then click New, Key. Create a key called Open that branches from Shell.
2. With the Open key selected, right-click the right pane, click New, Key and create a key called Command.
3. With the new Command key selected, right-click the (Default) key, click Modify, and set the (Default) value of Command to Explorer.exe. You can use any of the Explorer start-up switches or substitute the fully qualified pathname of any other program. Norton Navigator users would probably want to specify the path to the Navigator file manager.
4. Close regedit.exe. The change takes effect immediately.
When you open the Control Panel, you are presented with numerous icons that allow you to control many aspects of the Windows environment. To make these applets more accessible create a new folder in your Start Menu, and name it "Control Panel.{21EC2020-3AEA-1069-A2DD-08002B30309D}"

This will give you a cascading menu of the Control Panel applets on your Start Menu. You can also do the same with the following virtual folders:
- Fonts.{BD84B380-8CA2-1069-AB1D-08000948F534}
If you use Windows95's Dial-Up Networking to connect to your ISP (internet service provider), you've probably made a shortcut by dragging the session icon onto the desktop or Start Menu. Unfortunately the Connect To box still pops-up to make sure you want to connect. To get rid of the Connect To box download and install Dunce. Dunce is a freeware program that also has the ability to redial when disconnected and can launch any program when a connection has been established. I've been using it for the past four months and it is a great time saver.
Most mail programs allow for the use of a signature, a file that is automatically added to the end of every email you send. This file can contain your name, contact information, or just a meaningless quote. Unfortunately Microsoft didn't feel it necessary to include this feature in Exchange. To add a signature file to your messages in Exchange, download and install the freeware program Internet Idioms (12 kb).

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Internet Site of the Month

The Internet Site of the month for August is The Top Five List. The Top Five List is similar to David Letterman's Top Ten list, with the difference being that you can submit your own contributions. The list is created daily by a scattered few comedy writers and wannabees scattered all across the Internet. They pick a topic and come up with a list of applicable items. Some recent topics include: "The Top 15 Signs You've Hired the Wrong Elvis Impersonator" (#5 - Show consists solely of eating a fried peanut butter and banana sandwich and belching.) and "The Top 16 Signs Your Cat May Be Planning to Kill You" (#2 - You find a piece of paper labeled "MY WIL" which says "LEEV AWL 2 KAT.") As you can tell this is truly one of the more intellectually stimulating sites around.

Remember if you would like to be a Top Five List contributor you must take The Hideously Unfair and Completely Biased Top Five Contributor Test. I'm still waiting for one of my suggestions to make the list, so don't sweat it if you don't make the cut. At least my wife thinks I'm funny (looking).

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Cartoon of the Month

Thanks to Gabe Martin for placing his comic strip in the public domain. See more of Gabe's work at

The Borderline Cartoon Homepage

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Intranet Technology of the Month

The Intranet Technology of the month for August 1996 is WhatsUp 2.12, a network monitoring tool from Ipswitch. WhatsUp is an inexpensive, graphical network monitoring tool that will notify you by audio/visual alarms or pager when monitored network devices do not respond to polling. After installing and starting WhatsUp, you can create your database of network devices, referred to as a network map, or use the Scan IP feature to automatically poll all TCP/IP connected network devices. When polling, network devices can also be checked for a variety of services, such as WWW, SMTP, POP3, FTP, Telnet, News, or DNS. When the network map has been completed, WhatsUp is ready to start monitoring. WhatsUp monitors each of the network devices defined in the network map by sending a set number of ICMP (Internet Control Message Protocol) echo requests to the specified IP address and then tracking the responses. While monitoring, users can display up-to-the-minute status information about a particular network device by simply pointing and clicking on its icon.

WhatsUp is easy to use and does not require dedicated hardware. I'm currently monitoring a large enterprise network on the Windows 95 notebook computer that I'm writing this article on. WhatsUp may not have all the functionality of an HP OpenView ($megabucks), but it does a great job for the price ($145). WhatsUp will work with any 32-bit TCP/IP stack, such as those bundled with Windows 95 or Windows NT and is available for the Intel, PowerPC, and DEC Alpha platforms. You can download a 30 day evaluation copy of WhatsUp from Ipswitch's web site.

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