what is meant by n-tier architecture?
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interior architechture, is a speciality in design. For example and interior architect would be one of those people you see on trading spaces that decorate the house all fancy like.
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Computer System Architecture\nBy Morris Mano \nOther titles by Mano at this site
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Back in the eighties when network equipment vendors first started to hawk their wares, the term client/server was used to conjure up a host of fancy capabilities offered by the new hardware. Today, client/server has a very specific meaning that has nothing to do with hardware at all. Even so, most folks still associate the term client with the physical computers they are using and the term server with some other physical computer to which they are connected. There's a glimmer of truth there, to be sure, but today client/server means much more.\n\nWe're going to cover the essentials of client/server computing. We'll define one-tier, two-tier, three-tier, and n-tier client/server program architectures; we'll explain the difference between a thin client and a fat client; and we'll discuss the middleware concept. But first, you need to understand a few things about general software architecture.\n\nMost application programs have three major layers. On top is the presentation layer, which provides the human/machine interaction (the user interface). The presentation layer handles input from the keyboard, mouse, or other device and output in the form of screen displays. In the middle is the application or business logic, the functionality that gives the application program its character. Application logic makes the difference between an order entry system and an inventory control system, for example; it is often called business logic because it contains the business rules that drive a given enterprise. The bottom layer provides the generalized services needed by the other layers, including such things as file services, print services, communications services, and, perhaps most important, database services.\n\nFor simplicity, we will confine this discussion just to those programs needing database services. That's what most architects first think of when they hear the term client/server, but the general rules apply to any kind of service.\n\nThe number of tiers in a client/server application is determined by how tightly or loosely the three program layers are integrated. A one-tier application is one in which the three program layers are tightly connected. In particular, the presentation layer has intimate and detailed knowledge of the database structure. The application layer is often interwoven with both the presentation layer and the services layer. All three layers, including the database engine, almost always run on the same computer.\n\nOne-tier applications are easy to design and write, especially with today's modern software tools. It's also possible to create a multiuser one-tier application by running the application on several PCs and having them share the database. The database can be stored either on one of the PCs (a peer solution) or on a file server. Note that each PC running the application has its own copy of the database engine; only the data is shared, not the database logic itself.\n\nMultiuser one-tier applications are okay until the number of users gets large. The problem is that all the database work is performed in each client. For example, if the program needs to list all clients with the last name of Smith, all the information (indexes and data records) needed to resolve that query to the database must be transferred over the network. For some complex queries, a significant amount of data must be examined, perhaps even the entire database. At a more technical level, it is difficult to manage independent database engines to be sure that no conflict arises when two clients attempt to access or update the same record. This is called the record-locking problem.\n\nThe solution for the performance and technical problems associated with multiuser one-tier programs is two-tier client/server architecture. This type of application is written in mostly the same way as a one-tier application, with the exception that the database service (engine) no longer runs with the client. Instead, it
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- Multi-platform.\n- A syntax that is so easy that even a well-trainned monkey can pick up.\n- The effort of big companies like Sun and IBM for it to succeed.\n- Wide availabity of libraries and decent development tools.\n- Low TCO (total cost of ownership).
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It's an expansion of the client-sever concept:\nOfr example, you can have a data layer, then a business rules layer, and finally a GUI layer.
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Interconnection, an ISO standard for worldwide communications that defines a networking framework for implementing protocols in seven layers.\n\nApplication(Layer 7) \nThis layer supports application and end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are considered, and any constraints on data syntax are identified. Everything at this layer is application-specific. This layer provides application services for file transfers, e-mail, and other network software services. Telnet and FTP are applications that exist entirely in the application level. Tiered application architectures are part of this layer. \n\nPresentation(Layer 6) \nThis layer provides independence from differences in data representation (e.g., encryption) by translating from application to network format, and vice versa. The presentation layer works to transform data into the form that the application layer can accept. This layer formats and encrypts data to be sent across a network, providing freedom from compatibility problems. It is sometimes called the syntax layer. \n\nSession(Layer 5) This layer establishes, manages and terminates connections between applications. The session layer sets up, coordinates, and terminates conversations, exchanges, and dialogues between the applications at each end. It deals with session and connection coordination. \nTransport(Layer 4)\n This layer provides transparent transfer of data between end systems, or hosts, and is responsible for end-to-end error recovery and flow control. It ensures complete data transfer. \nNetwork(Layer 3)\n This layer provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions of this layer, as well as addressing, internetworking, error handling, congestion control and packet sequencing. \nData Link(Layer 2) \nAt this layer, data packets are encoded and decoded into bits. It furnishes transmission protocol knowledge and management and handles errors in the physical layer, flow control and frame synchronization. The data link layer is divided into two sublayers: The Media Access Control (MAC) layer and the Logical Link Control (LLC) layer. The MAC sublayer controls how a computer on the network gains access to the data and permission to transmit it. The LLC layer controls frame synchronization, flow control and error checking. \nPhysical(Layer 1)\n This layer conveys the bit stream - electrical impulse, light or radio signal -- through the network at the electrical and mechanical level. It provides the hardware means of sending and receiving data on a carrier, including defining cables, cards and physical aspects. Fast Ethernet, RS232, and ATM are protocols with physical layer components.
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When I do a design I use the three basic things to define a network. Physical connections, logical (ie network routing and switching, IP address schemes, etc...) and finally application information (usually I use tcp ports to define what is where since quite a few customers do not have a list of running apps). Once you have that information,  start from what you would consider your data center. Define it as above and start working your way out. Wireless presents an inetersting problem if the system is not strictly point to point. I typically use Visio to do my work in and then save it to pdf since alot of folks do not have visio as a viewer. Hope this helps, TX
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Please Do Not Throw Sausage Pizza Away\n\nApplication - email..telnet...ftp layer\nPresentation - encryptian layer\nSession - establish, manage, terminate connections between apps.\nTransfer - end to end error recovery and flow control\nNetwork - switching/routing, IP address\nData Link - encode/decode into bitsMAC address layer\nPhysical - bit stream (electrical pulses, light, or sound signal)\n\nThese are the 7 layers.  I am not sure where you got 5.  This is the correct order as well.
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This means there are three possible systems that control the application.  A front end (top tier) that displays the graphics to the user.  A middle layer (middle tier) that is acting as a broker for user requests and tapping the back end resources like a database.  A final back end (bottom tier) is providing data services most likely.\n\nAn example would be the following type of application:\nweb browser <-> An HTTP server <-> A database
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http://www.thirdage.com/features/tech/netglos/ here is some net lingo
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Yes, with asp.net 1.1 and 2.0 you can build up applications following a 3-tier architecture concept.\n\nThe use of 3-tier architecture empowers you with the flexibility to adapt your application in a modular fashion, ie without having to change the all code just because, for example, you want to be able to connect to different database engines.\n\nBy the consequent implementation of data providers in asp.net, you don't have to mix up connection strings and data queries with your logic code.\n\nMore on this topic under:
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Just looked at their website.This is an 'all-in-one ' package which may suit a greenfield development but if you are having to integrate with other middleware? Tomcat/JBOSS/Websphere/Microsoft MTS/.NET?.It's all very well using grids,parallelism and clustering , but you still have the page-lock or contention problem , i.e. what if 2 processes are after the same part of the DB? They have a Caching Edition , but this only postpones the problem . If you have less than 100 TPS then your usually OK with a single instance of MySQL. Any more than that and you start haibg to think a bit. ( take a look at the Oracle performance tuning sites , lots theree about disk / cache / processor configuring).
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NAS (Network Attached Storage) is used as a storage server with high perfomance.\n\nNetwork-attached storage (commonly abbreviated to NAS) systems are generally computing-storage devices that can be accessed over a computer network (usually TCP/IP), rather than directly being connected to the computer (via a computer bus such as SCSI). This enables multiple computers to share the same storage space at once, which minimizes overhead by centrally managing hard disks. NAS systems usually contain one or more hard disks, often arranged into logical, redundant storage containers or RAID arrays.\n\nThe protocol used with NAS is a file based protocol such as NFS or Microsoft's Common Internet File System (CIFS). In reality, there is a miniature operating system on the device such as DART on EMC's Celerra devices or Data ONTAP on NetApp NAS devices.\n\nA storage area network (SAN) is very similar, except it uses a block-based protocol and generally runs over an independent, specialized storage network.\n\nNAS devices become logical file system storage for a local area network. Thus the performance of NAS devices depends heavily on cached memory (the equivalent of RAM) and network interface overhead (the speed of the router and network cards). The benefit is that the device can become a giant neighborhood hard drive for a whole building. The disadvantage is that any constrictions in the local network will slow down the resulting access time.\n\nNAS was developed to address problems with direct attached storage, which included the effort required to administer and maintain "server farms", and the lack of scalability, reliability, availability, and performance. They can deliver significant ease of use, provide heterogeneous data sharing and enable organizations to automate and simplify their data management.\n\nIn addition, the price of NAS appliances has plummeted in recent years, offering flexible network based storage to the home consumer for little more than the cost of a regular USB or Firewire external hard disk.
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Hmmm.  Not really understanding your question, but I'll take a stab at it...  Yahoo mail works via a web browser, which is an application.  The Application Layer is Layer 7 in the OSI Model.  The OSI, or Open System Interconnection, model defines a networking framework for implementing protocols in seven layers. Control is passed down from one layer to the next, starting at the application layer in one station, proceeding to the bottom layer, over the channel to the next station and back up the hierarchy to layer 7 on the destination computer. \n\nLayer 7 supports application and end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are considered, and any constraints on data syntax are identified. Everything at this layer is application-specific. This layer provides application services for file transfers, e-mail, and other network software services. Telnet and FTP are applications that exist entirely in the application level. Tiered application architectures are part of this layer.
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Hi There,\n\nIt´s actually Redundant Array Of Independant Disks but sometimes inexpensive is used. For a more detailed summary of RAID see link below.\n\nSATA stands for Serial Advanced Technology Attachment. You can get a more detailed summary of this below also.\n\nHope This Helps!
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SOA (if you mean service oriented architecture) is essentially the connection of multiple services.  These services connect with each other and pass data.  This can be done over the internet.\n\nGrid computing is interconnectin of multiple computers to effectively use idle bandwidth.  \n\nThey are related in that they both involved interconnectivity and communication.  A Grid could also be used for SOA
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root user/ admin level,multi-path secured domain.\n\nAdd to your question if you're looking for a specific tech terminology.