Glossary |
Advanced Audio Coding, a “lossy” compression format capable of delivering relatively high quality at relatively low bit rates.
An alias token enables a card owner to access the same Sun Ray session with more than one physical token. This can be useful, for example, when a user needs a duplicate smart card.
The Sun Appliance Link Protocol, a suite of network protocols that enable communication between Sun Ray servers and DTUs.
Automatic Multigroup Hotdesking. See regional hotdesking.
Authentication headers, used as part of an IPSec implementation.
The Authentication Manager, using the selected authentication modules, decides what tokens are valid and which users, as token owners, have access to the system and sessions.
Although all tokens are used by the Authentication Manager to grant or deny access to Sun Ray sessions, this term usually refers to a user’s smart card token. See token.
Sometimes also referred to as switch fabric. A switch’s backplane is the pipe through which data flows from an input port to an output port. Backplane bandwidth usually refers to the aggregate bandwidth available amongst all ports within a switch.
To prevent clients from downloading firmware that is older than the firmware they already have, the administrator can set a barrier mechanism. The barrier mechanism symbol BarrierLevel is defined by default in the DHCP table of Sun Ray servers running version 2.0 or later of Sun Ray Server Software.
Context-adaptive binary arithmetic coding, a “lossless” entropy coding technique used in H.264/MPEG-4 AVC video encoding.
Controlled Access Mode, also known as kiosk mode. As of SRSS 4.0, the CAM module was replaced by a rewritten Kiosk module.
See token reader.
The most common type of wiring used in LANs. It is approved for both voice and data (at up to 100Mhz). Also called cat 5.
A common way to describe network services and the user processes (programs) of those services.
A device or program capable of encoding and/or decoding a digital data stream or signal.
Pressing the Cold Restart button terminates all sessions on a given server before restarting Sun Ray services. See restart.
The switch begins forwarding the incoming frame onto the outbound port as soon as it reads the MAC address, while it continues receiving the remainder of the frame.
Dynamic Host Configuration Protocol, which is a means of distributing IP addresses and initial parameters to the DTUs.
A set of one or more system boards that acts as a separate system capable of booting the OS and running independently of any other board.
Sun Ray desktop units were originally known as Desktop Terminal Units, hence the acronym. The are also referred to as Sun Ray thin clients, Sun Ray ultra-thin clients, and Sun Ray virtual display terminals.
Encapsulating Security Payloads, used as part of IPSec.
Physical and link-level communications mechanism defined by the IEEE 802.3 family of standards.
The unique hardware address assigned to a computer system or interface board when it is manufactured. See MAC address.
A unit that redirects packets from input ports to output ports. It can be a component of the Sun Ray interconnect fabric.
The process of transferring processes from a failed server to a functional server
Two or more Sun Ray servers configured to provide continuity of service in the event of a network or system failure. Sometimes abbreviated as FOG or HA (for high availability). The term high availability refers to the benefit of this type of configuration; the term failover group refers to the functionality.
When a DTU’s firmware is downgraded to an earlier version because it connects to a server running the earlier version, it needs to be connected to a filling station so that it can download newer firmware. For this purpose, a filling station can be any private network configured for Sun Ray services or any shared network in which the Sun Ray DHCP server is the only DHCP server.
See barrier mechanism.
See failover group.
Video output device that drives the video display. See virtual frame buffer.
File Transfer Protocol. The name of the Internet protocol and the program used to transfer files between hosts.
A standard for video compression developed by MPEG and VCEG for a wide range of bit rates and resolutions. Also known as MPEG-4 AVC (Advanced Video Coding) and MPEG-4 Part 10.
High availability. Sun Ray HA groups have traditionally been called failover groups.
Colloquial term for a screen, or display, or monitor, especially in a context where more than one is used in conjunction with the same keyboard and mouse, as in “multihead” feature.
See failover. The term high availability refers to a benefit of this type of configuration; the term failover group refers to the functionality.
The ability for a user to remove a smart card, insert it into any other DTU within a server group, and have the user’s session “follow” the user, thus allowing the user to have instantaneous access to the user’s windowing environment and current applications from multiple DTUs.
A pre-defined key that causes something to appear on your screen. A hot key is used to bring up the Settings screen on the Sun Ray DTU.
A property of a hardware component that can be inserted into or removed from a system that is powered on. USB devices connected to Sun Ray DTUs are hot-pluggable.
A session that is running on a Sun Ray server but to which no user (identified by a smart card token or a pseudo-token) is logged in.
Internet Key Exchange, a component of IPSec.
All the cabling and switches that connect a Sun Ray server’s network interface cards to the Sun Ray DTUs.
A collection of networks interconnected by a set of routers that enable them to function as a single, large virtual network.
The largest internet in the world, consisting of large national backbone nets (such as MILNET, NSFNET, and CREN) and myriad regional and local campus networks all over the world. It is a global collection of networks connecting a wide range of computers using a common protocol to communicate and share services.
Any network that provides similar services within an organization to those provided by the Internet but which is not necessarily connected to the Internet.
A unique number that identifies each host or other hardware system on a network. An IP address is composed of four integers separated by periods. Each decimal integer must be in the range 0-255 (for example, 129.144.0.0).
The assignment of an IP address to a computer system for a specified length of time, rather than permanently. IP address leasing is managed by the Dynamic Host Configuration Protocol (DHCP). The IP addresses of Sun Ray DTUs are leased.
The Internet Protocol (Security) set of protocols seeks to secure IP communications by encoding data packets through authentication headers (AH) and encapsulating security payloads (ESP) and by providing a key exchange mechanism (IKE).
A facility to run sessions without UNIX login under an anonymous user account. Kiosk sessions provide a preconfigured, usually restricted, software environment. The term kiosk mode was used interchangeably with CAM in earlier versions of SRSS. As of SRSS 4.0, however, this module was completely rewritten and is now officially called kiosk mode. The term CAM is meant to refer to implementations in SRSS 3.1 and earlier.
Local Area Network. A group of computer systems in close proximity that can communicate with one another through some connecting hardware and software.
The data link layer. In the OSI (Open Standards Interconnection) model, there are a total of seven layers. Layer 2 is concerned with procedures and protocols for operating the communication lines between networks as well as clients and servers. Layer 2 also has the ability to detect and correct message errors.
The CPU or computer on which a software application is running.
From the DTU’s perspective, the most immediate server in the LAN.
The process of gaining access to a computer system.
The name by which the computer system knows the user.
Media Access Control. A MAC address is a 48-bit number programmed into each local area network interface card (NIC) at the time of manufacture. LAN packets contain destination and source MAC names and can be used by bridges to filter, process, and forward packets. 8:0:20:9e:51:cf is an example of a MAC address. See also Ethernet address.
An object monitored by the Sun Management Center software.
If mobile sessions are enabled, a user can log into an existing session from different locations without a smart card, in which case the user name is associated with the session. This type of pseudo-token is called a mobile token.
For the purposes of the Sun Ray Server Software, the property of a session that allows it to follow a user from one DTU to another within a server group. On the Sun Ray system, mobility requires the use of a smart card or other identifying mechanism.
Authentication modules are used to implement various site-selectable authentication policies.
Microsoft Point-to-Point Compression protocol.
Maximum Transmission Unit, used to specify the number of bytes in the largest packet a network can transmit.
The process of enabling communication between Sun Ray servers over their Sun Ray network interfaces in a failover environment.
See head.
The process of transmitting multiple channels across one communications circuit.
See network address translation.
A set of names in which a specified ID must be unique.
Technically, the hardware connecting various computer systems enabling them to communicate. Informally, the systems so connected.
The IP address used to specify a network.
NAT. Network address translation typically involves the mapping of port numbers to allow multiple machines (Sun Ray DTUs in this case, but not Sun Ray servers) to share a single IP address.
An access point to a computer system on a network. Each interface is associated with a physical device. However, a physical device can have multiple network interfaces.
NIC. The hardware that links a workstation or server to a network device.
The time delay associated with moving information through a network. Interactive applications such as voice, video displays and multimedia applications are sensitive to these delays.
A number used by software to separate the local subnet address from the rest of a given Internet protocol address. An example of a network mask for a class C network is 255.255.255.0.
A network suite of protocols, organized in a hierarchy of layers called a stack. TCP/IP is an example of a Sun Ray protocol stack.
A mobile session on a Sun Ray DTU that does not rely on a smart card. NSCM requires a policy that allows pseudo-tokens.
On-screen display. The Sun Ray DTU uses OSD icons to alert the user of potential start-up or connectivity problems.
Pluggable Authentication Module. A set of dynamically loadable objects that gives system administrators the flexibility of choosing among available user authentication services.
A single PAM handle and run time state associated with all PAM items, data, etc.
A collection of files and directories that replace or update existing files and directories that prevent proper execution of the software on a computer system. The patch software is derived from a specified package format and can only be installed if the package it fixes is already present.
A mechanism that allows the entry of configuration parameters for a Sun Ray DTU from the attached keyboard.
(1) A location for passing data in and out of a computer system. (2) The abstraction used by Internet transport protocols to distinguish among multiple simultaneous connections to a single destination host.
Using the power cord to restart a DTU.
A Sun Ray session associated with a pseudo-token rather than a smart card token.
A user accessing a Sun Ray session without a smart card is identified by the DTU’s built-in type and MAC address, known as a pseudo-token. See token.
Microsoft Remote Desktop Protocol.
Originally known as Automatic Multigroup Hotdesking (AMGH), this SRSS feature allows users to access their sessions across wider domains and greater physical distances than was possible in earlier versions of SRSS. Administrators enable this feature by defining how user sessions are mapped to an expanded list of servers in multiple failover groups.
Remote Hotdesk Authentication, a security enhancement that requires SRSS authentication before users can reconnect to an existing session. RHA does not apply to Kiosk sessions, which are designed for anonymous access without authentication. RHA policy can be administered either with a GUI checkbox or with the utpolicy command.
Sun Ray services can be restarted either from the utrestart command or with the Warm Restart or Cold Restart buttons on the GUI. A a cold restart terminates all Sun Ray sessions; a warm restart does not.
The ability to pan to individual screens on a DTU with a single head that were originally created by a multihead group.
A computer system that supplies computing services or resources to one or more clients.
For the purposes of the Sun Ray Server Software, any application that can directly connect to the Sun Ray DTU. It can include audio, video, Xservers, access to other machines, and device control of the DTU.
A group of services associated with an authentication token. A session may be associated with a token embedded on a smart card. See token.
The ability for a session to “follow” a user’s login ID or a token embedded on a smart card.
Generically, a plastic card containing a microprocessor capable of making calculations. Smart cards that can be used to initiate or connect to Sun Ray sessions contain identifiers, such as the card type and ID. Smart card tokens may also be registered in the Sun Ray Data Store, either by the Sun Ray administrator or, if the administrator chooses, by the user.
An authentication token contained on a smart card. See token.
Simple Network Management Protocol
The spanning tree protocol is an intelligent algorithm that allows bridges to map a redundant topology and eliminates packet looping in Local Area Networks (LAN).
The switch reads and stores the entire incoming frame in a buffer, checks it for errors, reads and looks up the MAC addresses, and then forwards the complete good frame out onto the outbound port.
A working scheme that divides a single logical network into smaller physical networks to simplify routing.
The naming convention for the earliest incarnation of the Sun Ray thin client used the stock symbol for Sun Microsystems (SUNW) plus the letters “ut” to stand for Unix Terminal. Similarly, Sun Ray-specific commands begin with the characters “ut”.
Transmission Control Protocol/Internet Protocol (TCP/IP) is a networking protocol that provides communication across interconnected networks, between computers with diverse hardware architectures and operating systems.
Thin clients remotely access some resources of a computer server, such as compute power and large memory capacity. The Sun Ray DTUs rely on the server for all computing power and storage.
The time interval since some network event. Early versions of SRSS defined a tick as 1/50th of a second. It is now defined as 1/100th of a second, which is the usual SNMP convention.
The maximum allowed time interval between communications from a DTU to the Authentication Manager.
The Sun Ray system requires each user to present a token, which the Authentication Manager uses to allow or deny access to the system and to sessions. A token consists of a type and an ID. If the user uses a smart card, the smart card’s type and ID are used as the token. If the user is not using a smart card, the DTU’s built-in type and ID (the unit’s Ethernet, or MAC, address) are used instead as a pseudo-token. If mobile sessions are enabled, a user can log into an existing session from different locations without a smart card, in which case the user name is associated with the session. A pseudo-token used for mobile sessions is called a mobile token. Alias tokens can also be created to enable users to access the same session with more than one physical token.
A Sun Ray DTU that is dedicated to reading smart cards and returning their identifiers, which can be associate with card owners (i.e. with users).
Servers in the same failover group “trust” one another.
Uniform Resource Identifier, the generic term for all types of names and addresses that refer to objects on the World Wide Web.
Uniform Resource Locator. A standard for writing a textual reference to an arbitrary piece of data in the World Wide Web (WWW). The syntax of a URL is protocol://host/localinfo where protocol specifies a protocol to use to fetch the object (such as HTTP or FTP), host specifies the Internet name of the host on which to find it, and localinfo is a string (often a file name) passed to the protocol handler on the remote host.
The name a computer system uses to identify a particular user. Under UNIX, this is a text string of up to eight characters composed of letters (a-z and A-Z), digits (0-9), hyphens (-), and underscores (_), for example, jpmorgan, jp_morg, jpm-888. The first character must be a letter.
A session that is running on a Sun Ray server and to which a user (identified by a smart card token or a pseudotoken) is logged in.
See SUNWut.
Informal name of the SMPTE 421M video codec standard, now a supported standard for Blu-ray Discs and Windows Media Video 9.
A virtual machine containing a desktop instance that is executed and managed within the virtual desktop infrastructure, usually a Windows XP or Vista desktop accessed through RDP.
A region of memory on the Sun Ray server that contains the current state of a user’s display.
See restart.
Windows Media Audio data compression file format and codec developed by Microsoft.
A collection of associated users who exist in near proximity to one another. A set of Sun Ray DTUs that are connected to a Sun Ray server provides computing services to a work group.
The new default Xserver for Sun Ray Server Software 4.1 and later on Solaris.
A process which controls a bitmap display device in an X window system. It performs operations on request from client applications. Sun Ray Server Software contains two Xservers: Xsun, which was the default Xserver in previous versions of SRSS, and Xnewt, which is the default Xserver for SRSS 4.1 and later. Xnewt enables the latest multimedia capabilities.
Simple, lossless mechanism to store images or a sequence of images.
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