IP Addresses
As a computer doctor and guru, I see so many instances where business owners cause themselves untold
number of headaches as far as Information Technology, IT, services are concerned. Smooth operations,
from the computer side of things, are enhanced when a network is well documented. Even if you have
a small office with only two computers, proper documentation is the key. I see that you think that
this does not concern you. But, if you use a broadband connection or Internet connection sharing,
this document is for you. Developing a network is not as complicated as one would think,
especially with any of the Microsoft operating systems. Just string a cable from one computer to
another, and you have a working network.
Yet, implementing the above mentioned action is fraught with danger and headaches if careful planning
is not undertaken. This is the scenario, first there are only two computers. Next, you want to share
printers. Let’s not forget about sharing data and other computer devices. Before you know it,
you have a rat’s nest of networking that becomes a nightmare if something breaks or a third
computer is added. So let’s backup and do it right. Note, the techniques, I will discuss with
you are not the only way to properly setup a computer network. Yet, these techniques have saved me
a lot of headaches when dealing with networks that have grown from only 4 computers to over 135
computers and other complications.
Let’s first look at a computer model. In this model there are several hardware items. These
items include servers, routers, hubs, networked printers, end user computers, and Internet gateways.
For the sake of simplicity, we will use the Internet protocol, IP, to have all the devices talk and
listen to each other. In this network there are two sets of IP addresses. One is for the Internet
side of the network. This is commonly referred to as the Wide Area Network, WAN, address. The other
set of IP addresses are for your internal network which is referred to as a Local Area Network, LAN.
The WAN IP addresses are assigned by your Internet Service Provider, ISP. The ISP may consist of a
flavor of DSL, a cable modem distribution, T-1 connection, or satellite connection. Either way,
you have an IP address or a set of IP addresses you utilize to get on the Internet. These addresses
may be fixed and referred to as static IP addresses or you can have a variable address, dynamic IP
address, which changes every time you access the Internet. What ever the case, the IP address you use
is assigned to you.
On the other hand, when dealing with your internal networking system, you have a choice of several public
domain IP addresses. A public domain IP address can never be used to access the Internet. These addresses
are used for internal or Local Area Networks only. Further discussion of public domain IP addresses is
ancillary to the topic at hand.
I personally use the public domain subnet of 192.168.10.1 through 192.168.10.253. This allows you the
use of 252 distinct IP addresses. One never uses the IP address of 192.168.10.127. Now that we have our
internal IP addresses, we can set assignments for their utilization in our network.
I personally use addresses, 192.168.10.1 to 192.168.10.19 for gateways, routers, and managed hubs. A
gateway allows access of information or resources between heterogeneous, (different), networks. A
router is a very sophisticated gateway that can store and modify routes from one network to another
as is needed. A managed hub allows one to segregate portions of a LAN from other portions of the network
while maintaining a commonality of connection between the computers and resources connected within the
boundaries of that segregated segment of the network. All of the devices in this group must have a
unique static IP address. Therefore, I can make a maximum of 19 additions to my system before I have to
reuse an address.
The next level of IP address assignments are for servers. I define servers as running applications, file
sharing, Domain Name Server, (DNS), DHCP, database, web hosting servers, email, monitoring servers,
and/or video streaming. You can have a server that accomplishes one or more of these functions. Because
one is apt to have more servers than routers, gateways or hubs, I usually assign the address range of
192.168.10.20 through 192.168.49 to this group of devices. All of the devices in this group must have
a unique static IP address.
There is a type of server that I do not normally include in the aforementioned group of servers. This
server type may have three different flavors. These flavors are a modem server, a facsimile server,
an all-in-one printer/copier server, or a standard printer server. The reason is that you sometimes
need to allow certain people who need no direct access to the server access to these devices. Because
there is a plethora of these devices, I assign the address range from 192.168.10.50 to 192.168.10.99
to this group of resources. All devices and resources in this group must have a unique static IP
address.
The last group of the network is that individual computer workstations. This is always going to be the
largest group in the network. Some of the computers in this group may need a static IP address.
Therefore, I use a range of from 192.168.132 to 192.168.10.199 for static addresses. Because it is
necessary to allow people in on a temporary basis, I use the address range 192.168.10.200 to
192.168.10.253 for dynamic addresses.
In conclusion, a well ordered networking assignment of IP addresses allows you to find the source of
trouble. In addition, after a power failure or the resetting of a device you may receive an error
message that there is an IP address conflict. By having a well documented IP address list, you can
with very little trouble find the source of the problem.
Naming Conventions
In the first installment of this series, we dealt with assignment of IP addresses. While IP addresses are
wonderful things, they are at best difficult to remember. Therefore, as the groups of computer geeks were
assembling documents and policies on what later became known as the Internet, someone suggested simple
easy-to-remember names for computers and devices. Today, too many computer geeks and technicians are too
staid in their computer naming schemes. I constantly see names like SERVER001, USER9001, and others.
If anyone remembers the science fiction movies and superhero shows of the 1970’s and 1980’s,
computers had real worldly names. We all remember HAL9000. Why not for the easy of acceptance us a
similar naming convention in your organization? I setup a community based free access computing center in
Oakland CA in 1997. I was a volunteer. Initially, the Program Administrator and his Technical Assistant did
not see the humor and power of using cartoon characters as names for the pieces of the network. In time,
they came to appreciate the gesture as the outside users were fast learners because of the cartoon names.
Even among the group of older elderlies, (76 years old and above), the cartoon names worked. Most of these
people were deathly afraid of computers but wanted to learn so that they could talk to their grand and
great grand children. The cartoon character names worked. Soon these older elderlies had no problem
complaining that Mr. Tibbles, (a variant of Officer Tibbles), was running too slow.
They all knew of Officer Tibbles from the Top Cat cartoon series from Hanna Barbara. The major players were
Top Cat, Choo Choo, Fancy Fancy, Spook, Benny the Ball, and Brain. By giving servers names to which many are
familiar, learning and ownership of the network becomes organic. In more elaborate and extensive settings,
I have used the Flintstones. This is good for multiple domain systems. I used the names of communities as
the names of the different domains. There was Bedrock, Hollyrock, and Frantic City. Frantic City was the
place of the annual national convention of the Fraternal Order of Water Buffaloes.
Thus with this scenario, servers in the various domains could be called Fred, Wilma, Barnie, Betty, Mister
Slate, Bam Bam and Pebbles. If that is too much for your taste, you can use other themes. Although I
just outlined a scenario for a multiple domain system, this regime works well for a small office.
If you have just a few computers, routers, and printers some of the themes for naming conventions I suggest
would be:
• The twelve disciples of Jesus Christ, (no disrespect intended);
• The major Mythological Gods of Mount Olympus;
• The major Mythological Gods of Asgard;
• Snow White and the Seven Dwarfs;
• Santa Claus and the nine reindeer, (hint: one had a red nose);
Whatever naming convention you use for your computer network, there are some simple rules to keep in mind:
• Use a naming convention that is easy to remember;
• All names MUST be single words, numbers, or number & word combinations - No SPACES
• Do not use any special characters such as ~!@#$%^&*()-+=}{|\\??><"''
• Keep the names short, (try writing thisismyowncompany twenty times)
• Document all of your information, that is keep a notebook in a safe place
• Have fun but please don't insult
In review, you now have a naming scheme and and IP addressing scheme for your network. This is the first set
of the networking protocol that is required. Document everything and safe keep the document, it will same many
hours of searching when the crisis hits. It will. They always do.
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