File Name: what is server and client in network .zip
Traditional network management tools NMT are centralised in nature, as a result of which they are not flexible enough when large control network e. SCADA network design is desired for.
- An overview of HTTP
- Client–server model
- A STUDY ON CLIENT SERVER SYSTEM IN ORGANIZATIONAL EXPECTATIONS
- Client–server model
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An overview of HTTP
The primary function of Oracle Net is to establish and maintain connections between a client application and an Oracle database server. Oracle Net is comprised of several communication layers that enable clients and database servers to share, modify, and manipulate data. A database server is the Oracle software managing a database, and a client is an application that requests information from a server. Information passed from a client application sent by the client communication stack across a network protocol is received by a similar communications stack on the database server side.
The process flow on the database server side is the reverse of the process flow on the client side, with information ascending through the communication layers. Figure illustrates the various layers on the client and on the database server after a connection has been established. In the OSI model, communication between separate computers occurs in a stack-like fashion with information passing from one node to the other through several layers of code, including:.
Character set differences can occur if the client and database server run on different operating systems. The presentation layer resolves any differences. It is optimized for each connection to perform conversion when required. TTC provides character set and data type conversion between different character sets or formats on the client and database server. At the time of initial connection, TTC is responsible for evaluating differences in internal data and character set representations and determining whether conversions are required for the two computers to communicate.
The Oracle Net foundation layer is responsible for establishing and maintaining the connection between the client application and database server, as well as exchanging messages between them. TNS provides a single, common interface for all industry-standard OSI transport and network layer protocols. TNS enables peer-to-peer application connectivity, where two or more computers can communicate with each other directly, without the need for any intermediary devices. On the client side, the Oracle Net foundation layer receives client application requests and resolves all generic computer-level connectivity issues, such as:.
On the server side, the Oracle Net foundation layer performs the same tasks as it does on the client side. It also works with the listener to receive incoming connection requests. In addition to establishing and maintaining connections, the Oracle Net foundation layer communicates with naming methods to resolve names and uses security services to ensure secure connections. Oracle protocol support layer is positioned at the lowest layer of the Oracle Net foundation layer. This layer supports the following network protocols:.
The network protocol is responsible for transporting data from the client computer to the database server computer, at which point the data is passed to the server-side Oracle protocol support layer. The server communication stack uses the same layers as the client stack with the exception that the database uses Oracle Program Interface OPI.
For example, an OCI request to fetch 25 rows would elicit an OPI response to return the 25 rows after they have been fetched. Oracle offers two JDBC drivers. The Oracle database server supports many other implementations for the presentation layer that can be used for Web clients accessing features inside the database in addition to TTC. The listener facilitates this by supporting any presentation implementation requested by the database. A network protocol is responsible for transporting data from the client computer to the database server computer.
This section describes the protocols used by the Oracle Protocol Support layer of the Oracle Net communication stack. It contains the following topics:. TCP is the transport protocol that manages the exchange of data between hosts. IP is a network layer protocol for packet-switched networks. IPv6 addresses the shortcomings of the currently used IPv4. The primary benefit of IPv6 is a large address space derived from the use of bit addresses.
A bit IP address is generally represented as 8 groups of 4 hexadecimal digits, with the colon : symbol as the group separator. For example, the following address is in a valid IPv6 format:. Each hexadecimal digit in the address represents 4 bits, so each group in the address represents 16 bits. The following addresses represent the first and last hosts in the DB subnet:. In shorthand notation, consecutive zero fields can be compressed with a double colon :: separator, as shown in the following equivalent notations:.
Classless routing was designed to overcome the exhaustion of address space in the IP class system and the unmanageable growth in the size of routing tables. For example, in the notation IPv4-mapped addresses are a subclass of IPv6 addresses in which the following conditions are true:. Example shows the same IP address in different notations. The first address uses standard IPv6 notation.
The second address is an IPv4-mapped address in which the last 32 bits use dotted-decimal IPv4 notation. The last address uses a shorthand notation to compress the consecutive zero fields.
A host may have different IPv4 and IPv6 interface configurations. The following configurations are possible for a host:. A single host may also use different types of IP address. For example, a domain name server may associate a dual-stack host both an IPv4 and an IPv6 address or only an IPv6 address. The IP address configurations that are not supported are the following:. Figure shows possible host and interface configurations.
The network connectivity of a host refers to its ability to communicate with another host over a network. For example, if a dual-stack client must communicate with an IPv6-only server, then the network and router must make end-to-end communication between these hosts possible.
The IPv6 capability of a host is partially dependent on the network and partially dependent on its interface and address configuration. Both dedicated and shared server modes are supported. Components in this release of Oracle Database 11 g support IPv6 in the configurations described in "IPv6 Network Connectivity" , with the following exceptions:.
SSL stores authentication data, such as certificates and private keys, in an Oracle Wallet. When the client initiates a connection to the database server, SSL performs a handshake between the two using the certificate. During the handshake, the following processes occur:.
The client and database server negotiate a cipher suite made up a set of authentication, encryption, and data integrity types to apply to the messages they exchange. Depending on its configuration, the database server sends its certificate to the client in a message encrypted with the client's public key. The database server may also send a request for the client's certificate in the same message.
The client decrypts this message by using its own private key, then verifies that the database server's certificate bears the certificate authority's signature. If required, the client may send the user's certificate to the database server. The certificate ensures that the user's information is correct and that the public key actually belongs to that user. The database checks the user certificate to verify that it bears the signature of the certificate authority.
The Named Pipes protocol is a high-level interface providing interprocess communications between clients and database servers using distributed applications.
One server-side process creates a named pipe, and the client-side process opens it by name. What one side writes, the other can read. If a remote Oracle database is running on a host system that supports network communication using Named Pipes, then Oracle Net enables applications on a client to communicate with the Oracle database using Named Pipes.
Skip Headers. Presentation Layer Character set differences can occur if the client and database server run on different operating systems. Oracle Net Foundation Layer The Oracle Net foundation layer is responsible for establishing and maintaining the connection between the client application and database server, as well as exchanging messages between them.
On the client side, the Oracle Net foundation layer receives client application requests and resolves all generic computer-level connectivity issues, such as: The location of the database server or destination How many protocols are involved in the connection How to handle interrupts between client and database server based on the capabilities of each On the server side, the Oracle Net foundation layer performs the same tasks as it does on the client side.
Oracle Protocol Support Layer Oracle protocol support layer is positioned at the lowest layer of the Oracle Net foundation layer. Figure shows the stack communication layers used by JDBC drivers. Using Oracle Net Stack Communication for Web Clients The Oracle database server supports many other implementations for the presentation layer that can be used for Web clients accessing features inside the database in addition to TTC. Understanding Oracle Protocol Support Layer A network protocol is responsible for transporting data from the client computer to the database server computer.
For example, the following address is in a valid IPv6 format: DBCA Each hexadecimal digit in the address represents 4 bits, so each group in the address represents 16 bits. The following configurations are possible for a host: Only an IPv4 interface, in which case the host is an IP4-only host. Only an IPv6 interface, in which case the host is an IPv6-only host. Both an IPv4 and IPv6 interface, in which case the host is a dual-stack host.
An IPv6-only host cannot use an IPv4 address. IPv6 Network Connectivity The network connectivity of a host refers to its ability to communicate with another host over a network. A client or server host is IPv6-capable if it meets the following criteria: It has a configured IPv6 interface. It can connect to other hosts using the IPv6 protocol.
During the handshake, the following processes occur: The client and database server negotiate a cipher suite made up a set of authentication, encryption, and data integrity types to apply to the messages they exchange. Book List. Master Index. Contact Us. Legal Notices.
Client-server architecture , architecture of a computer network in which many clients remote processors request and receive service from a centralized server host computer. Client computers provide an interface to allow a computer user to request services of the server and to display the results the server returns. Servers wait for requests to arrive from clients and then respond to them. Ideally, a server provides a standardized transparent interface to clients so that clients need not be aware of the specifics of the system i. Clients are often situated at workstations or on personal computers , while servers are located elsewhere on the network, usually on more powerful machines. This computing model is especially effective when clients and the server each have distinct tasks that they routinely perform.
Client—server model is a distributed application structure that partitions tasks or workloads between the providers of a resource or service, called servers , and service requesters, called clients. A server host runs one or more server programs, which share their resources with clients. A client usually does not share any of its resources, but it requests content or service from a server. Clients, therefore, initiate communication sessions with servers, which await incoming requests. Examples of computer applications that use the client-server model are email , network printing, and the World Wide Web. The client-server characteristic describes the relationship of cooperating programs in an application.
Most network applications are based on the client-server model: ▫ A server process and one or more client processes. ▫ Server manages some resource.
A STUDY ON CLIENT SERVER SYSTEM IN ORGANIZATIONAL EXPECTATIONS
Client Server Architecture is a computing model in which the server hosts, delivers and manages most of the resources and services to be consumed by the client. This type of architecture has one or more client computers connected to a central server over a network or internet connection. This system shares computing resources. Client Server Architecture Figure 1.
A client is a program that runs on the local machine requesting service from the server. A client program is a finite program means that the service started by the user and terminates when the service is completed. A server is a program that runs on the remote machine providing services to the clients. When the client requests for a service, then the server opens the door for the incoming requests, but it never initiates the service. A server program is an infinite program means that when it starts, it runs infinitely unless the problem arises.
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