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The Internet Protocol Adapter Operating System (IPAD-OS) is the foundation of all our products exclusively used to achieve levels of protection, reliability and service impossible with any general purpose operating system.

What is the Circle-I logo?

The IPAD-OS is the center. Every complete Internet connection has a number of functions and services in common. These common components are always found at the core of every mature Internet presence - no matter how small or large - and include routing, firewall, email, domain name service, web service, file service, management and diagnostic tools.

Draw a circle around these core functions and you have IPAD-OS.

The IPAD-OS includes all of these core functions in one, well integrated, very powerful and easy to use package. Yes, these are all of the dull and repetitive services every technical person hates to create yet again. With the IPAD-OS these required functions are a snap to configure and manage, allowing you to spend your valuable time on more interesting and profitable things - like your business and your customers.

The IPAD-OS is different!

The IPAD Operating System (IPAD-OS) is unique, even among other embedded operating systems, because it holds the coveted distinction of nearly two decades on the public Internet without a single kernel-level security breach. The operating system is so secure, it may be the only true bullet proof platform.

This is a feat impossible to reach with general purpose operating systems - like Windows, Linux and UNIX - that require frequent security patches and updates to close holes after they are discovered. The very first IPAD-OS kernel version released in 1996 is just as secure today as the day it was released. We have the luxury to focus all our attention on useful features instead of chasing down daily security problems.

Imagine an operating system that can do real work unprotected on the public Internet for years without needing a single security patch. This is the IPAD-OS!

How can the IPAD-OS be so secure?

The IPAD-OS was designed from the ground up to protect itself first, and never includes any built-in holes. For example:

  • There are no special user accounts built into the kernel. You control all of the account names and permissions in each server - where user accounts should be.
  • There are no external programs or libraries and absolutely no way to remotely run foreign code through buffer overruns or any other means. There is zero potential for hacking into the IPAD-OS directly, and virtually no way to infect the IPAD-OS with a virus.
  • All IPAD-OS servers have access to proven secure and reliable functions in the kernel. This totally removes the need to duplicate functions that could introduce security problems. It also makes the IPAD-OS much more compact and noticeably faster.

How can the IPAD-OS protect you?

Only a firewall built inside (not on top of) a true self-protecting operating system can protect you and your important data. This is not your average bolt-on after market firewall technology, and there is never a need to harden the IPAD-OS.

The True IP Address Expansion firewall technology inside the IPAD-OS has proven absolutely impenetrable in countless private, commercial and government penetration security tests. It has also proven diamond hard in some of the worst, most abusive and demanding settings around the world.

IPAD-OS is all about reliable quality service.

Very few people buy the IPAD-OS just for the protection and security. IPAD owners want service and there are some nice features here too.

All of the servers are designed inside the IPAD-OS kernel for maximum speed and performance - with minimum overhead.

This design approach causes many experienced general purpose operating system administrators to question how to restart a service when there is a problem. The short answer is that the IPAD-OS simply runs without any need to constantly monitor, reboot or restart anything. While there are ways to stop and start individual services, these commands are mainly for development testing to purposefully break things in the lab.

The vast majority of IPAD-OS users simply relax in the comfort of email, web, DNS and FTP servers that just run like they should - no baby sitting needed.

Major Features Inside IPAD-OS

Industrial-strength Routing

In order for information to go from one place to another, it must be routed.

The IPAD-OS is an industrial strength router with full support for classless routing and split horizon route definitions. You can easily route both public and private address space in virtually any direction and combination to, through or from your network. Protecting your routing with filters and True IP Address Expansion proxy firewall technology is easy. If your connection requires it, you can also use dedicated router protocols to dynamically exchange route information without need for human intervention, or even dynamically assign an IP address to your IPAD router.

The high-end commercial router inside the IPAD-OS has some other amazing features to help tame users, machines or protocols that like to consume all of your available bandwidth. This is done through an easy bandwidth shaping technology that enables you to fine tune exactly how well each protocol performs. If you have VOIP phone service the IPAD's router can be tuned so all other Internet traffic stays out of the way and your voice calls remain responsive and clear.

Traffic Filtering

Protection and security are important on the Internet. You want to make sure information that should stay in the office stays there while letting public traffic out.

The packet filtering and bandwidth shaping ability in the IPAD-OS router allows you to control the data flow for all incoming and outgoing Internet traffic. It's a very powerful tool that allows you to specify who can and can't reach sites or services. For example, if you don't want anyone from inside the firewall accessing a specific service like SMB/ CIFS file shares outside your network, you can easily restrict access to that service. As far as your network is concerned, the rest of the world does not use that protocol.

You can also create custom firewall rules that work seamlessly with the automatic True IP Address Expansion technology built into the IPAD-OS.

Your custom rules can include dynamic bandwidth shaping to give preference to selected users or services as needed. This includes a fully configurable burst window where full bandwidth is granted for a period of time before being restricted. Bandwidth shaping can be applied to the protocol, interface or any IP address you choose. It fully supports setting different speeds for sending and receiving.

True IP Address Expansion

IP addresses are like telephone numbers computers on the Internet use to talk to each other. There are approximately 4 Billion IP addresses available on the Internet. While this may sound like a very large number, it is becoming a problem with the rapidly growing demand for more connections every day. This problem goes away with True IP Address Expansion proxy firewall technology.

True IP Address Expansion works by taking a single, public Internet Protocol (IP) address and expanding it into full featured private IP addresses. Machines on your LAN can use these IP addresses without any special settings, and almost no protocol restriction. Do you want to add a new machine to your LAN? Simply plug it in. There is no need to worry if you have enough public IP address space - and there is no need to tell your ISP or anyone else. It just works like you want.

Unlike other firewall technologies, True IP Address Expansion works with a wide variety of typically firewall unfriendly applications, such as CU-SeeMe, RealAudio, RealVideo, VDOnet Live, Internet Phone, VOIP, and many others. And there is no speed degradation so you can use all the bandwidth you pay for!

This unique firewall is exclusive to the IPAD-OS platform and is the only firewall technology available, at any price, that is totally invulnerable to kernel-level security attacks. The highest security and highest performance combined with the highest compatibility means you can connect your LAN to the Internet with confidence again. When the IPAD's firewall detects a critical attack, all connectivity to the attacker is automatically terminated. It is designed to always fail on the side of protecting you and your data.

And finally, True IP Address Expansion makes configuring LAN workstations quick and easy. The automatic Dynamic Host Configuration Protocol (DHCP) server configures your LAN workstations with their proper IP address, netmask, DNS server, and so on. There's no need for you to think about or manage this on your own.


The most common driving reason why every business connects their network to the Internet is email. The IPAD meets this demand head-on with a proven, industrial strength email server - built right into the IPAD-OS. This server easily supports thousands of email accounts. A whole host of email routing features let you copy, redirect, auto-respond, store and distribute mail in almost any combination of ways you can imagine.

The IPAD email server also has some very robust spam filtering tools to control the junk (including virus email), while allowing the real mail through to your users. These spam fighting tools give you a very high degree of control over your email right down to the individual user where one user gets the maximum spam protection including blocking mail from servers in unwated countries while another user gets a different level of filtering or no filtering at all.

Public and private black lists can be used to block out known problem sources and mail containing links to known spamvertized web sites before they reach your users. You can even create your own black list with the IPAD-OS and publish it to others.

These IPAD-OS spam fighting tools do not require any subscription or additional licensing fees to use, and are yours to keep for as long as you want. This alone can save you many times more than the cost of the IPAD itself.

In addition to email filtering, all email in and out of the server can be locally or remotely archived as needed for SEC or government compliance, subpoena compliance or employee monitoring. This is not the default operating mode, but is an example of the flexibility available to meet your needs.

Mailing lists

The list server built into the IPAD-OS is very flexible to the point it can be anything from a super email copier (looks like normal email, not a list server) to a full blown discussion group with footers, subject tagging, macros and optional moderator filtering. The list server includes some fancy ways to manage the list membership and remove old addresses - even if bounced or redirected mail does not contain the original recipient's address.

IPAD mailing lists allow you to easily create email discussion groups. Participants simply need to send email to a single address, and everyone on the member list will see the message. You can also create moderated mailing lists with one or more moderators, and optional password protection, to protect the list from abuse.


There are many cases where having a human respond to email is either not desirable or not possible. For example, if someone wants to receive information about your company's address, phone number, and so on, it doesn't make sense for someone to spend time retyping the same information over and over again - or even copy it from a file.

The IPAD's auto-responders allow you to define an email address, such as info@example.com, that automatically returns an email message containing any information that you define. You can optionally pass responder messages through to another destination if you still want a person to read that email.

Mail Forwarders

In some situations, you may wish email to be re-directed to a different destination. For example, if an employee leaves your organization, the transition can be smoother if email destined for the old address is sent to the boss instead. Email forwarders are not limited to local delivery. Any email received by the IPAD-OS can be redirected to any mail server anywhere on the Internet. So if the boss wants his business email delivered to his home address, that is easy to do with your IPAD.

Other Email Features

The IPAD-OS provides you with many more email features, including:

  • Copies. The IPAD can automatically make copies of inbound or outbound email messages. For example the sales manager may wish to receive a copy of all mail sent to the sales team, or you may need to keep an archival copy of all email sent through your server for SEC compliance. This is easy with an IPAD mail server.
  • Rejects. You may explicitly reject messages based on the SMTP source (from) or destination (to) addresses.
  • Selective Exemption. Some customers and family members may unwittingly have email accounts on blacklisted mail servers. These addresses can be selectively exempted from spam filtering while still retaining full spam protection from the offending server.
  • Custom White Lists. Spammers are trying to reduce the value of public black list services by polluting the list with legitimate addresses. The IPAD allows you to create your own white list to silently ignore the pollution that effects your users while still getting full value out of a public black list.
  • Spam Traps. The IPAD can have multiple special email addresses that can track unwanted email activity (i.e. spam, phishing, trolling). If the activity happens more often than you allow, the IPAD passively blocks the connection.

WWW Service

The web server inside the IPAD-OS is different than the typical HTTP server because it lets you safely publish virtually any content onto the Internet without risk. The web server is designed for highest protection, and holds the distinction of never being successfully hacked. This extremely high level of protection is primarily due to a design that does not permit external programs (called CGI) to run. Several bullet-proof internal CGI programs such as Server Side Includes (SSI), forms processing and page counters are included in the web server to make data collection and tracking easier. All web server activity can also be recorded in the CERN common logging format so any popular web log processing utility can be used to analyze your traffic.

You can define any combination of virtual (no dedicated IP address) and standard (unique IP address for each) web servers on the IPAD-OS for serving information internally to your LAN or externally to the public Internet.

Lab testing has proven the web server in the IPAD-OS comfortably out-performs all available bandwidth, even when running on modest hardware. This is a true powerhouse web server.

Web Forms Processing

Eventually you will need to collect information from your web users. It might be an elaborate survey, an order form, or a simple poll. No matter what you need, the IPAD-OS web form processing will get the data safely into your hands.

You design the HTML documents so the form is displayed to the user exactly how you want, and the IPAD-OS web server reliably collects the data in the format you specify. Web form data can be recorded in a log file and/or sent to you through email. The IPAD web server can also optionally send a confirmation email response to the user to let them know the web server received their information.

Web Page Counters

A popular feature on a new web page is a page counter to show how many times a page has been received. To the viewer and the author, a counter can show popularity.

The IPAD-OS web server allows you to create uniquely named page counters for any HTML document hosted on an IPAD web server. You may create as many page counters as you wish - and control how they are displayed.

FTP Servers

FTP is one of the most efficient ways to transfer multiple files through the Internet. This protocol is very popular for sending web content to the web server, or publishing files in a logical directory structure that users can see.

Since the IPAD-OS does not have any reserved user account names, and does not contain any pre-defined privileged accounts, your protection remains incredibly strong. Account names like root, admin and sysadmin are available and can be assigned to normal user accounts without risk or limitation.

Using anonymous FTP, your customers can use any web browser to navigate and download files hosted on your IPAD FTP server. You may configure the FTP server in a variety of ways, allowing both anonymous and individual password protected user access. You have full control to define the virtual root directory for each user, creating their own limited domain of control inside the IPAD-OS file system.

There is no limit to the number of FTP servers you may create and host on your IPAD.

Internet Domain Name Service

DNS is like the Internet telephone book. When you want to call someone on the telephone, you look up their name in the phone book and call the listed number. DNS works the same way, allowing you to use www.example.com to connect to a web site instead of having to remember a long IP address number like

With the IPAD-OS you control your own piece of the collective Internet phone book known as the Internet Domain Name System. The IPAD Domain Name Server lets you host and control all the Internet domain names you want including making up your own local domain names. The IPAD-OS imposes no restrictions.

You can also provide backup (secondary) DNS hosting for virtually any Internet domain name hosted on any DNS server connected to your LAN or the public Internet.

Your Own Domain Name

Your Internet domain name identifies your site with an easy to remember name. You still need to register your Internet domain name with a public registrar. Your authorized IPAD reseller can provide this service for you if desired.

Once you've registered your domain name, you can freely add all the subdomain names you want. For example, the domain names of most web sites begin with a www, such as www.example.com. If you want to make web.example.com and wow.example.com, this is very easy with your IPAD-OS DNS server and is fully under your control.

Dial-up Service

Once your LAN is connected, you may want to extend it so that you or your colleagues can call in from home or on the road. Checking email or browsing the web is but a phone call away!

The IPAD-OS supports from 1 to 96 dial-up ports to connect any combination of analog modems, ISDN adapters and almost any serial device you want. (IPAD 5000 required for 96 serial ports.) You have full control over who can connect and use the ports along with connection time limits and inactivity timeouts - just like an ISP. In fact this is the service that built plenty of Internet Service Providers into the large companies they are today. The IPAD 5000 even includes full RADIUS accounting and logging servers capable of controlling both local serial connections and external terminal servers.


The IPAD 5000 supports robust telnet service for legacy systems that do not directly support TCP/ IP. Up to 96 serial lines, which may optionally include up to 32 TIPX lines, can be dedicated to telnet access on the IPAD 5000. The IPAD 2500 does not include this feature.

Much more...

There is a whole lot more, but this gives you an idea of just how different the IPAD-OS is from anything else available today.

In the spirit of under-promising and over-delivering, the next step is for you to see an IPAD for yourself. We believe you will be pleasantly surprised.