Metropolitan Area Sun Ray Services
The IT costs for companies, organizations, and government bodies is a modern challenge. Costs frequently grow out of control and are hard to calculate. IT operations cost money, but not all costs are visible. Computer problems, primarily at the user level, generate productivity problems on a massive scale, and with productivity loss, your income decreases as expenses increase. Deploying Sun Ray_ appliances in your network environment is a powerful weapon against such hidden costs, and because of the modest pricing, the cost of deployment is reasonable.
The desktop computational device can be obsoleted by deploying Sun Ray appliances without loss of computational power to the end user. Metropolitan Area Sun Ray Services (MASS) is a method to get the good things that Sun Rays provide, out from the small LAN and into the wide open spaces of metropolitan area networks (MANs, see "What is a Metropolitan Area Network?" on page 11). This technology also opens a market for entire new types of operations, as described in this article.
Sun Ray appliances have a great potential to be a viable alternative to the common workstation. By using true broadband technologies, deploying Sun Ray appliances on a massive scale in MAN environments is possible. The advantage is that centralized data centers can be run by a few specialists. This method eliminates production losses and incompatibility problems at the user level, reduces overall costs of operation, increases data integrity, and practically eliminates the risk of virus attacks. The MAN could be a CityNet, and the end users could be anybody from the common citizen (surfing the Internet, retrieving mail, or home office use), to small firms, franchising companies, corporations, government bodies, health care, or other organizations.
Today, all IT operations consist of various servers, but on the user side, we are still bound to the desktop computer. The purpose of this paper is to describe a viable thin client alternative, the functions of the components that form it, and how to massively deploy such clients over broadband technology in MAN-type networks.
This article is intended for people working with IT architecture or IT strategies with the intent to rationalize IT operations, especially if these operations are spread over a large geographic area.
The Vision of Sun Ray Appliances in a MAN-type Network
The immediate possibilities of MASS can be appreciated at once. MASS can be viewed as an innovative method of deploying Sun Ray appliances in various quantities, at different locations, and still connect them to a centralized data center in a robust way. This concept can be sufficient for the individual company or organization. MASS is scalable too. Instead of using a Sun Ray backnet (a private Sun Ray network) and its Sun Ray server, you could consider a Sun Ray data center hosting a large number of Sun Ray domains, each with its own backnet.
MASS could grow to become a valuable asset for large MANs like a CityNet. With MASS, the owners of a CityNet can offer its users maintenance-free access to the Internet while providing an appliance, complete with surfing capabilities, mail, and an excellent office packagethe StarOffice_ software.
Because the Sun Ray servers and application servers are situated in a data center, user data can be backed up centrally, thus offering data protection to the individual user. Sun Ray appliances deployed to ordinary users can run processes in user mode on the servers. This feature makes them practically immune to the virus plague that constantly rages the Internet these days.
Taking one step further, it is possible to facilitate easy and inexpensive outsourcing for everything from small firms to franchising companies, and large corporations for mail, web access, office, and portal carrying applications.
Although Sun Ray appliances use a special private network, it is possible to configure the broadband/Ethernet switch (the proxy switch to which the Sun Ray appliance is connected) so that the appliance has access to other networks. This configuration enables standard workstations to coexist with Sun Ray appliances on the same switch (using port VLANs), should the need arise. Proxy switches could also be deployed in residential areas using one or more fibers and common narrowband techniques. Users could have access to 10 Mbps or 100 Mbps connections even at home. The Sun Ray appliance could function as an Internet "surf board", office carrier, and mail tool. The field is open for net-bound applications on portals to be instantly accessible by Sun Ray users without locking out workstations or other types of appliances or computers. This maintenance-free surf board could be an option in an Internet subscription.
Other uses for MASS could be in educational services. Instead of maintaining hundreds of workstations, plug-and-play Sun Ray appliances could be set up. If a Sun Ray appliance malfunctions, the only thing that has to be done is to replace it with another unit. No reinstallation or upgrading is needed, and possible licensing costs could be incorporated in the fee for access to the MASS network. Servers could either be outsourced or be placed at a location within the educational service's premises. Sun Ray appliances could be spread to schools over the MAN, regardless of distance within the MAN. Hospitals, government bodies, and so on are also potential MASS customers.
The main advantage for MASS users in a MAN area is that no unexpected costs will occur. Hardware upgrades every six months are no longer necessary, and companies and firms do not have to keep an expensive IT department anymore. MASS is easy to establish. It can expand as needed, and it is easy to maintain.
Establishing MASS is a "win-win" situation for everybody involved, and it will encourage growth and development of new companies and ventures that do not exist today. This article describes how all of this can be achieved.
What is a Sun Ray Thin Client?
The general idea of a thin client is to provide zero administration at the user level. Sun Ray appliances do not have a local operating system, and they do not need to be preconfigured to function. The work involved when installing a Sun Ray appliance is limited to connecting it to its keyboard, mouse, screen, and the network. After the Sun Ray appliance is powered up, it is instantly accessible to a user.
Sun Ray appliances have a very small footprint, and they are extremely rugged and dependable. Because they do not need forced cooling, Sun Ray appliances lack fans, making them silent. Also, there are several versions of Sun Ray appliances. Some are built into flat screens, while others can use modern multisync VGA-type video display units.
Sun Ray appliances are centrally administered by very powerful Sun Ray control software, making them suitable as a highly cost-effective alternative to the traditional workstation.
An extremely useful feature of the Sun Ray appliance is its smart card function. When using smart cards, the session displayed on the appliance is tied to the identification number of the smart card, not to the appliance itself. This feature makes it possible to move the current session to another Sun Ray unit simply by removing the card and inserting it into another Sun Ray appliance. If a smart card is not available, the Sun Ray appliance can be used anyway, but the session will be tied to the physical Sun Ray unit. The smart card function makes the Sun Ray appliance both session persistent and session independent at the same time. In the Sun Ray Server software version 1.3, there is even a non-smart-card mobility feature, enabling user sessions to be hot-desked without a smart card.
How a Sun Ray Appliance Works
A Sun Ray appliance can be described as a a terminal device with no local computing environment, and requires a connection to a Sun Ray server. Sun Ray appliances connect to their servers through a dedicated Sun Ray network using standard TCP/IP. In this article, we refer to that network as a backnet.
Sun Ray appliances communicate using UDP and need a high quality network. Thus, Sun Ray networks must be practically error free (less than 0.1 percent packet loss), cannot be overloaded, and must have low latency and sufficient bandwidth, or the Sun Ray appliance might lose its connection to the server and stop working.
A Sun Ray server can, in principle, be any reasonably modern Sun computer with sufficient capacity. When choosing and sizing servers, we recommend following the directions given by the Sun Ray development team. However, modest resources can be used to form a Sun Ray server if you use other servers as application carriers.
At boot time, a Sun Ray appliance establishes a link to the Ethernet, and then uses DHCP to get its network and Sun Ray vendor specific parameters. When the Sun Ray appliance is up and connected to its Sun Ray server, the server perceives it as yet another video card (and additional hardware such as a mouse, keyboard and so forth).
In a minimal environment, the Sun Ray server is also the application carrier. Sun Ray users log in to run their programs, and displays them on their local screen. In larger deployments, the Sun Ray server has a connection to a public network, or frontnet, such as a corporate LAN segment. Sun Ray users can have their application servers elsewhere (as usual in a true client/server environment).
When traversing the frontnet, the Sun Ray appliance is seen as originating from the IP address of the Sun Ray servers frontnet interface and not from the real IP address of the Sun Ray appliance (no routing occurs between the backnet and frontnet). The Sun Ray appliance is identified through the display number issued by the Sun Ray server; thus the display data can be sent to the correct device.
Because Sun Ray appliances are not running anything but microcode locally, the processes they open on the servers are not dependent on the state of the Sun Ray device. You can use several methods to determine what process belongs to which Sun Ray appliance, but these methods are beyond the scope of this article.
Sun Ray appliances have smart card readers. Using them is optional; users can usually log in on an application server without using smart cards. If smart cards are used, the display number is tied to the smart card identification code. Removing the smart card will free that particular Sun Ray appliance for others to use. Inserting the card again will display the open session associated with the card. Removing the card and inserting it in another Sun Ray appliance causes the session to be displayed there. The purpose of this feature is twofold. You can remove the card without logging out, and your session is available, without logging in, the next time you need to use the application server. The other benefit is that your session is not bound to a geographical location, but instead it can be moved around (flexible office, meetings, and so forth).
Until now, a limitation of the Sun Ray technology has been the modest scalability and inability to effectively function over long distances while retaining a high degree of redundancy. Naturally, there is a demand for these functions and, by using broadband networking techniques, these demands can be met today.