IP Addresses

IP addresses –why?  If your computer is on a network, then you probably have an IP address assigned.  This address is a unique number used to identify your computer on the network.  Addresses consists of twelve numbers divided into four sets of three numbers ranging from 0 to 255 and are identified as XXX.XXX.XXX.XXX.  There are several types on IP addresses that are used on a network.  They are listed below.

Static IP Address – When a static IP address is assigned to a computer, that address is permanent and does not change when the computer is turned off or being rebooted.  If the address needs to be changed, it must be handled manually on the computer.

Dynamic IP Address – If a dynamic IP address is assigned, the address usually comes from the network server.  This address will change each time the computer reboots.  The most popular protocol used for providing dynamic addresses is called Dynamic Host Configuration Protocol or DHCP.

Public IP Address – This type is usually assigned to an Internet Service Provider (ISP) to identify your home network to the outside world.  Comcast and AT&T are examples of ISPs.

Private IP Address – This address is used between private networks within the same company.

Gateway IP Address – This is used as a bridge for connecting networks so that data can be transferred between a number of computers.

IP Address Classes – IP address classes are an organizational structure to determine the maximum potential size for a given computer network.  The address defines which of the four sets of numbers would be used to identify the network.

• Class A – Each address has a number between 0 and 127 in the first set of three numbers.  This type of allocation is generally given to very large networks such as international companies.  An example would be 10.0.0.0.
• Class B – Each address has a number between 128 and 191 in the first set of three numbers.  These blocks are reserved for Internet Service Providers (ISP) and large networks.  An example would be 135.0.0.0.
• Class C – Each address has a number between 192 and 223.  These numbers are reserved for small to mid-size companies.
• Class D – IP addresses in this class are reserved for a service called Multicasting.   Multicasting is a way to send communications from a single sender or network to multiple receivers.
• Class E – IP addresses in this class are reserved for experimental use.

MAC Address (Media Access Control) – A MAC number is a unique number that associates actual network card in the computer.  It serves as a convenient way to distinguish between computers.  MAC addresses are written in hexadecimal number system made of 16 symbols.  The hexadecimal number system includes numbers 0 through 9 plus alpha characters A through F.  Not all MAC addresses will have 16 characters.  Most MAC addresses are printed on hardware devices.

An example of a MAC address might look like 01-1B-63-84-45-E6.

Each of the IP address formats helps make up the network and has a different function.  IP addresses can be intimating and confusing at times, but having a basic understanding of how each one functions can assist you in solving network issues when they arise.

I hope you found this information helpful.  Please feel free to forward it to others.  If you would like to learn more about this topic or would like to request a topic, please contact me. If you missed any past newsletters or would like a printed copy, visit my website www.mdsystemsolutions.com.

Until next time…Happy Computing!!!