The Server

Xetex Xebra gets its efficiency by having a program called the server running on one computer on the network. Don't be confused by the two different meanings of the word 'server'. Some computer manufacturers sell specially designed computers to function as network servers. When we talk about the server for XETEX Xebra, we are talking about a program that runs on a computer, not the computer that it runs on. The word 'client' can cause confusion too. In terms of a network, a client is a computer program that accesses a server. It has nothing to do with whether the person using the computer is one of your customers or clients. It will be your employees that use Xebra clients.

The Xebra data base is so efficient that, as long as the Xebra server is running on a static public IP address, it can be accessed by clients running anywhere in the world where an Internet connection is available. We run Xebra servers for many customers at our data center in Reading, PA. Your Xebra Advantage Subscription allows you to select the option of having XETEX host your server. There is no additional cost for this service. We take responsibility for keeping your server running and backing up your data. All you need to be concerned with is a reliable Internet connection for your office. All data passing between the server and the client is encrypted.

Each XETEX customer gets their own encryption and the server will only respond to clients with the right encryption. Security is an important consideration. There are two types of security.

1. Keep your data from being seen or manipulated by unauthorized people. The server program can not display data or allow data entry. Only the client programs can do that. When we run Xebra servers for customers, they are run from computers that don't even have a full time monitor. Yes we have the ability to create a client to look at your data. We use this on rare occasions to resolve problems. When we do, we ask you permission and have you create a temporary password for us.

2. The other aspect of security is keeping your data safe and making sure that it is running. No company can make a guarantee of 24/7 operation. Equipment breaks! At our data center, we always have extra machine capacity available so that if we have a problem with one computer, we can move your server to another one within minutes. In addition, we have duplicate communication lines that use different telephone companies, routers, and internet service providers so that if we have a problem with one, the other one is used. The switching is so quick that operators do not even know that it occurred.

If you have decided to host your own Xebra server, there are some additional things that you need to consider.

1. Except for single user systems, you should have a separate, dedicated, computer to run your Xebra server. This computer should not be used to run other programs, especially ones that require operator interface. You do not need to go out and buy a 'server' computer. The Xebra server will run on any computer that meets minimum requirements. Most of the least expensive newer computers have the capability to run the Xebra Server.

•	Minimum System Requirements (The Xebra Server will run, but performance is impacted):

2. You must have provisions to make a reliable backup of the Xebra data on your server on a daily basis. Backups are not made to protect you IF you have a hard disk failure, they are made to protect you WHEN you have a hard disk failure. Backups should be kept off-site. Backups take time and attention and are easily relegated to the back burner when your staff is busy. Automatic tape backups are not recommended. Our experience has been that less than10% of the customers who have needed their tape backups have been able to recover all of their data from them. XETEX offers an automatic off-site backup that sends your data to our data center on a nightly basis. Not only does this service provide a reliable back up, it provides an emergency recovery procedure. When you are doing your own backups, you have to wait to get a new computer or have your computer repaired. We can start a server with your data and have your company running within an hour. When your hardware is repaired or replaced, we send your data back to you.

All of the computers in an office are networked using a LAN (Local Area Network). This networking is accomplished by using wires or wireless signals to connect each computer to a switch or hub. This switch or hub may also be connected to a shared Internet connection. XETEX Xebra does not require anything special with the network. The standard TCP/IP protocol is required.

Xetex Xebra requires an internet connection. The minimum requirement is for dial-up connection that allows you to download software updates. Depending on your other needs, your Internet requirements may get more sophisticated and more expensive. The chart on page 14 shows two typical Xebra configurations and the internet connection requirements at various points.

Dial-up connections are generally the least expensive option. They are slow and subject to being disconnected unexpectedly. US$ 10-20 per month.

Broadband connections provide greater speed and are slightly more expensive than dial-up. Cable and DSL are popular lower cost broadband services. US$ 30 - 50 per month.

Broadband with static IP address - If you are hosting your Xebra Server and wish to allow access to your system over the Internet you must have a broadband connection with a static IP address. A static IP address gives your computer a permanent network address that does not change. US $70 - and up.

The best option for your Internet connection depends on the area where your office is situated. DSL is becoming more widely available, but still won't work in some areas. Cable and DSL with variable IP addresses are designed for home use. You cannot host a mail server or a website, nor can you allow client programs outside of your office to access your Xebra Server. Most cable providers and many DSL providers will not provide static IP addresses. If they do, you will pay a premium because it is considered a 'business' connection. Leased T1 lines start at hundreds of dollars a month and require expensive routers.

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Remote single user Xebra clients with a dial-up connection are satisfactory for short term use. They are a little slower than being in the office, but are still workable even with 28.8 cellular connections. If someone is working from the same location on a regular basis, upgrading to a broadband connection is probably appropriate.

•	Remote offices that share an Internet connection between several computers should have a broadband connection.

•	If XETEX is hosting your Xebra Server, your main office should have a broadband connection. It does not need to have a static IP address.

•	If you are hosting your own Xebra Server, your own connection needs will depend on whether you are running real-time E-Commerce and whether you require remote client access. If you need either of these features you require a broadband connection with a static IP address.

•	If you are hosting your own server and all of your Xebra clients are connecting over your LAN and you are not running E-Commerce, all you need is a dial-up Internet connection to download software updates.

•	Other activities on your network can alter your Internet connection requirements. If your art department, for example, is e-mailing large files regularly, they can use up all of the connection bandwidth while the file is being uploaded.