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Records 19 - 30 Oracle9i Database Administration. Fundamentals I. Volume 1 • Student Guide. DGC Production September D New Oracle9i features such as Oracle Managed Files, Automatic segment Oracle9i DBA Fundamentals I. Understanding the Oracle9i Server Architecture. 1 Records 16 - 32 Introduction. Course Objectives I Oracle 9i Enterprise Edition I Database Administrator Tasks I 1 Oracle Architectural Components.

Oracle 9i Fundamental-1 Pdf

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Fundamentals II subparagraph (c)(1)(ii) of DFARS , Rights in Technical Data and Explain solutions included with Oracle9i for. Each pdf file contains a unique serial number associated with your particular name Chapter 1: Oracle9i Database Administration and Management Features . Oracle is a registered trademark and Oracle9i is a trademark or registered trademark of Oracle .. of on the upper floors of #1 World Trade Center in New York City. .. comprehend, it fundamentally changes the nature of the relationship.

Please contact us for the latest prices and special offers. The exam fees are not included in the course fee unless specifically stated. If you are from out of town, we can arrange accommodation close to our centre.

Accommodation rates vary depending on the time of year. Included in your course fees: Tuition Breakfast and lunch on course days Teas and coffees Training Material Attendance certificate.

What other branches do you have in SA or in the world? We only train in Cape Town. What books do I get with this course? You will receive a course text book which you can take away with you to keep after the course. What are the dates for the course? See our schedule page: No, the exam is not included in the price. Exam prices vary from centre to centre. The exam is a multiple test, on computer at an authorised testy centre.

The results are made known immediately. If you fail the test, you must book it again at a future date and will pay again. Oracle Course Outline Networking Overview [ ] Explain solutions included with Oracle9i for managing complex networks [ ] Describe Oracle networking addon solutions.

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Full Name Comment goes here. Are you sure you want to Yes No. Search for IT online training Providers at http: Sheeraz Mirani. Subramani Arumugam. Show More. Consider the following questions to determine the security of a network: What kinds of information will be sent across the Oracle network?

This may involve sending the data in a format that makes it tamperproof and also ensures that the data cannot be captured and read by parties other than the client and the intended Oracle server. In large organizations with many Oracle services, this can be a management and administration issue.

Interfacing Existing Systems with New Systems The following issues should be considered when existing computer systems must communicate with Oracle server networks: If so, what is the frequency and what transport mechanisms should be used? Will the Oracle server need to send information back to the existing system? Here are some of the key responsibilities of the DBA in the Oracle network implementation process: Network Configurations T here are three basic types of network configurations to select from when you are designing an Oracle infrastructure.

The simplest type is the singletier architecture. This has been around for years and is characterized by the use of terminals for serial connections to the Oracle server.

Applications utilizing single-tier architecture are sometimes referred to as green-screen applications because most of the terminals using them, such as the IBM terminal, have green screens.

Single-tier architecture is commonly associated with mainframe-type applications. This architecture is still in use today for many mission-critical applications, such as Order Processing and Fulfillment and Inventory Control, because it is the simplest architecture to configure and administer.

When a single-tier architecture is being used, users interact with the database using terminals.

These terminals are non-graphical, character-based devices. Figure 1. In this type of architecture, client terminals are directly connected to larger server systems such as mainframes. All of the intelligence exists on the mainframe, and all processing takes place there. Simple serial connections also exist on the mainframe. Although no complex network architecture is necessary, a single-tier architecture is somewhat limiting in terms of scalability and flexibility.

Because all of the processing must take place on the server, the server can become the bottleneck to increasing performance. Also, two-tier architecture allows the client computer to share the application processing load. To a certain degree, this reduces the processing requirements of the server. The two-tier architecture does have some faults, even though at one time, it was thought to be the panacea of all networking architectures. Unfortunately, the main problem, that of scalability, persists.

The slash represents the invisible component of the two-tier architecture and the one that is often overlooked: When prototyping projects, many developers fail to consider the network component and soon find out that what worked well in a small environment may not scale effectively to larger, more complex systems. There was a great deal of redundancy in the two-tier architecture model because application software was required on every desktop. As a result of this scenario, many companies end up with bloated PCs and large servers that still do not provide adequate performance.

What is needed is a more scalable model for network communications. That is what n-tier architecture provides. Instead of dividing application processing work between a client and a server, you divide the work up among three or more machines. The n-tier architecture introduces middleware components, one or more computers that are situated between the client and the Oracle server, which can be used for a variety of tasks.

Some of those tasks include the following: This common interface means less training of staff and also increases the potential reuse of client-side application components. N-tier architecture makes it possible to take advantage of technologies such as networked computers. Such computers can make for economical, low-maintenance alternatives to the personal computer.

Because much of the application processing can be done by application servers, the client computing requirements for these networked computers are greatly reduced. In addition, the processing of transactions can also be offloaded to transaction servers, which reduces the burden on the database servers. The n-tier model is very scalable and divides the tasks of presentation, business logic and routing, and database processing among many machines, which means that this model accommodates large applications.

In addition, the reduction of processing load on the database servers means that the servers can do more work with the same amount of resources. Also, the transaction servers can balance the flow of network transactions intelligently, and application servers can reduce the processing and memory requirements of the client see Figure 1. It is responsible for handling client-to-server and server-to-server communications, and it can be configured on the client, the middle-tier application, web servers, and the Oracle server.

Oracle Net also manages the flow of information in the Oracle network infrastructure. First, it is used to establish the initial connection to the Oracle server, and then it acts as the messenger, passing requests from the client back to the server or passing them between two Oracle servers. Basically, Oracle Net handles all negotiations between the client and server during the client connection.

These products allow n-tier architectures to be used in the enterprise, which increases the flexibility and performance of application designs. To learn more about these products and some of the features of Oracle Net, read the following sections, which mirror the five categories of networking solutions that Oracle Net provides: This support is handled transparently and allows Oracle Net to establish connectivity to a wide range of computers and a wide range of operating environments.

SANs are special configurations of hardware that are used for situations in which multiple servers need high-speed communications between them.

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The new Virtual Interface VI protocol is lightweight and works with a specific hardware configuration to relieve network activity responsibility from the CPUs and place it on special network adapters. A for details on the use, configuration, and restrictions on the VI protocol. This guide may be obtained from the Oracle Technology Network website at technet. This range allows users to bridge existing systems to other Unix or PC-based systems, which increases the data access flexibility of the organization without making wholesale changes to the existing systems.

These features allow clients to connect to applications interfacing with an Oracle database via a web browser. By utilizing features such as Secured Sockets Layer SSL , client connections can obtain a greater degree of security across the Internet. Directory Services: Directory Naming Directory Naming allows for network names to be resolved through a centralized naming repository. It provides a simplified way to manage directories of information, whether this information is about users in an organization or Oracle instances connected to a network.

By utilizing Oracle Internet Directory, you ensure security and reliability of the directory information because information is stored in the Oracle database. As of Oracle9i, Directory Naming has become the preferred method of centralized naming within an Oracle environment, replacing the Oracle Names Server.

The Oracle Names Server can still be utilized in Oracle8i and earlier versions, however. OID can be used with both Oracle8i and 9i databases. In Oracle9i, the OID runs as an application. The OID is a scalable architecture, and it provides mechanisms for replicating service information among other Oracle servers.

OID also provides security in a number of ways. Also, an administrator can maintain policies that grant or deny access to services. These policies are defined for entities within the Oracle Internet Directory tree structure. Oracle Shared Server Oracle Shared Server formerly known as Multithreaded Server is an optional configuration of the Oracle server that allows support for a larger number of concurrent connections without increasing physical resource requirements.

This is accomplished by sharing resources among groups of users. Connection Manager Oracle Connection Manager is a middleware solution that provides three additional scalability features: Multiplexing Connection Manager can group together many client connections and send them as a single multiplexed network connection to the Oracle server.

This reduces the total number of network connections the server has to manage. Network access Connection Manager can be configured with rules that restrict access by IP address. This rules-based configuration can be set up to accept or reject client connection requests.

Also, connections can be restricted by point of origin, destination server, or Oracle server.

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Cross-protocol connectivity This feature allows clients and servers that use different network protocols to communicate. Connection Manager acts as a translator, providing two-way protocol conversion. Oracle Connection Manager is controlled by a set of background processes that manage the communications between clients and servers.

This option is not configured using the graphical Oracle Net Manager tool. Advanced Security The threat of data tampering is becoming an issue of increasing concern to many organizations as network systems continue to grow in number and complexity and as users gain increasing access to systems. Sensitive business transactions are being conducted with greater frequency and, in many cases, are not protected from unauthorized tampering or message interception. Oracle Advanced Security, formerly known as the Advanced Security Option and the Advanced Networking Option, not only provides the tools necessary to ensure secure transmissions of sensitive information, but it also provides mechanisms to confidently identify and authenticate users in the Oracle enterprise.

When configured on the client and the Oracle server, Oracle Advanced Security supports secured data transactions by encrypting and optionally checksumming the transmission of information that is sent in a transaction. These security features ensure that data transmitted from the client has not been altered during transmission to the Oracle server. Oracle Advanced Security also gives the database administrator the ability to authenticate users connecting to the Oracle servers.

In fact, there are a number of authentication features for ensuring that users are really who they claim to be. These are offered in the form of token cards, which use a physical card and a user identifying PIN number to gain access to the system; the biometrics option, which uses fingerprint technology to authenticate user connection requests; Public Key; and certificate-based authentication. Another feature of Oracle Advanced Security is the ability to have a single sign-on mechanism for clients.

Single sign-on is accomplished with a centralized security server that allows the user to connect to any of the Oracle services in the enterprise using a single user ID and password. Oracle leverages the industrystandard features of Kerberos to enable these capabilities.

Kerberos is an authentication mechanism based on the sharing of secrets between two systems. This greatly simplifies the privilege matrix that administrators must manage when they are dealing with large numbers of users and systems.

Firewall Support Firewalls have become an important security mechanism in corporate networks. Firewalls fall into two broad categories: IP-filtering firewalls IP-filtering firewalls monitor the network packet traffic on IP networks and filter out packets that either originated or did not originate from specific groups of machines.

The information contained in the IP packet header is interrogated to obtain this information. Vendors of this type of firewall include Network Associates and Axent Communications. Proxy-based firewalls Proxy-based firewalls prevent information from outside the firewall from flowing directly into the corporate network.

Instead, the firewall acts as a gatekeeper, inspecting packets and sending only the appropriate information through to the corporate network. This prevents any direct communication between clients outside the firewall and applications inside the firewall. Check Point Software Technologies and Cisco are examples of vendors that market proxy-based firewalls.

Oracle works closely with the vendors of both types of product to ensure support of database traffic through these types of mechanism. This product can be incorporated into the firewall architecture to allow database packets to pass through the firewall and still maintain a high degree of security. Know Thy Firewall It is important to understand your network infrastructure, the network routes you are using to obtain database connections, and the type of firewall products you are using.

I have had more than one situation in which firewalls have caused connectivity issues between a client and an Oracle server.

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For instance, I remember what happened after a small patch was applied to a firewall when I was working as a DBA for one of my former employers. In this case, employees started experiencing intermittent disconnects from the Oracle database.

It took many days of investigation and network tracing before we pinned down the exact problem. When we did, we contacted the firewall vendor and they sent us a new patch to apply that corrected the problem.

It turns out that the networking routes for the development staff had been modified to have connections routed through a new firewall. This firewall was configured to have a connection timeout after 20 minutes of inactivity, which was too short an amount of time for this department. These are examples of the types of network changes that a DBA needs to be aware of to avoid unnecessary downtime and to avoid wasting staff time and resources.

Heterogeneous Services Heterogeneous Services provide the ability to communicate with non-Oracle databases and services. These services allow organizations to leverage and interact with their existing data stores without having to necessarily move the data to an Oracle server.

These products allow Oracle to communicate with non-Oracle data sources in a seamless configuration. Heterogeneous Services also integrate existing systems with the Oracle environment, which allows you to leverage your investment in those systems. These services also allow for two-way communication and replication from Oracle data sources to non-Oracle data sources.

Transparent Gateway The Transparent Gateway product seamlessly extends the reach of Oracle to non-Oracle data stores, which allows you to treat non-Oracle data sources as if they were part of the Oracle environment.

In fact, the user is not even aware that the data being accessed is coming from a non-Oracle source. This can significantly reduce the time and investment necessary to transition from existing systems to the Oracle environment.

Transparent Gateway fully supports SQL and the Oracle transaction control features, and it currently supports access to more than 30 non-Oracle data sources. Generic Connectivity Generic Connectivity provides a set of agents, which contain basic connectivity capabilities.

You can also use ODBC as a stand-alone connection solution. These drivers can be obtained from Oracle or third-party vendors. Because these drivers are generic in nature, they do not provide as robust an interface to external services as does the Transparent Gateway.

External Procedures In some development efforts, it may be necessary to interface with procedures that reside outside of the database. These procedures are typically written in a third-generation language, such as C. When a call is made, a process will be started that acts as an interface between Oracle and the external procedure.

This callout process defaults to the name extproc. The listener is then responsible for supplying information, such as a library or procedure name and any parameters, to the called procedure. These programs are then loaded and executed under the control of the extproc process. The Oracle Net Stack Architecture T he Oracle Net software is comprised of a series of programs that form a type of stack architecture.

Each of these programs is responsible for handling various aspects of network communications, and each functions as a layer of the stack. This section discusses the architecture of the Oracle Net stack and defines the responsibilities of each portion. To successfully complete the OCP exam, you need to understand the structure and responsibilities of the Oracle Net stack.

The upper layers of the model handle responsibilities such as communicating with the application and presenting data.

The lower layers are responsible for transporting data across the network. The upper layers pass information, such as the destination of the data and how the data should be handled, to the lower layers.

The lower layers communicate status information back to the upper layers. Table 1. As you can see from this table, this layered approach allows for a separation of responsibilities. It also allows for the separation of the logical aspects of network communications, such as presentation and data management, from the physical aspects of communications, such as the physical transmission of bits across a network.

TABLE 1. Accepts commands and returns data. Presentation Layer Settles data differences between client and server. Also responsible for data format. Session Layer Manages network traffic flow. Determines whether data is being sent or received.

Transport Layer Handles interaction of the network processes on the source and destination. Error correction and detection occurs here. Network Layer Delivers data between nodes. Data Link Layer Maintains connection reliability and retransmission functionality. Physical Layer Transmits electrical signals across the network. Each of the layers of the Oracle communications stack has characteristics and responsibilities that are patterned after the OSI model.

Oracle interacts with the underlying network at the very highest levels of the OSI model. In essence, it is positioned above the underlying network infrastructure and communicates with the underlying network. Oracle uses Oracle Net on the client and server to facilitate communications.

The communications stack functions as a conduit to share and manage data between the client and server. The layers of Oracle communications stack are as follows: The client process makes network calls that traverse down the Oracle Net client layers to the network protocol. The server receives the network request, processes it, and returns the results to the client. This layer is responsible for interacting with the user, which involves providing the interface components, screen, and data control elements.

Interfaces such as forms or menus are examples of the application layer. The OCI layer exists on the client only. Because the OCI is an open architecture, third-party products can write applications that interface directly with this layer of the communications stack.

The Two-Task Common layer acts as a translator, converting values from one character set to another. It is based on the Transparent Network Substrate TNS , which allows Oracle Net to be a very flexible architecture, interfacing with a wide variety of network protocols.

The TNS interface shields both the client and server from the complexities of network communications. At this layer of the communications stack, Oracle Net interfaces with the other layers of the stack and their underlying protocols.

It is this layer that provides the level of abstraction necessary to make Oracle Net a flexible and adaptable architecture, and it is this layer that compensates for differences in connectivity issues between machines and underlying protocols. The Oracle Net Foundation layer has several sublayers: Network interface NI sublayer The network interface sublayer provides a common interface on which the clients and servers can process functions.

This layer of the stack is also responsible for handling any break requests. Network routing NR sublayer This is where Oracle Net keeps its network roadmap of how to get from the source or client to the destination or server. Network naming NN sublayer This layer takes network alias information and changes it into Oracle Net destination address information.

Network authentication NA sublayer This layer is responsible for any negotiations necessary for authenticating connections. Network session NS sublayer The network session layer handles the bulk of activity in an Oracle network connection.

This layer is responsible for such things as negotiating the initial connection request from the client. It is also responsible for managing the Oracle Net buffer contents and passing the buffer information between the client and the server. This becomes the entry point into the underlying network. This layer maps the Oracle Net Foundation layer functions to the analogous functions in the underlying protocol.

There are different adapters for each protocol supported. The Network Specific Protocol Layer This is the actual transport layer that carries the information from the client to the server. These protocols are not supplied with the Oracle software and must be in place to facilitate network communications. It is analogous to the OCI on the client. This layer is responsible for server-toserver communications, whereas the OPI is used in client-server communications and is used in distributed environments where databases communicate with each other across database links.

An Object Request Broker is a piece of software that handles the routing of object requests in a distributed network. This type of connectivity would be used if an application were accessing Java procedures that were written and stored in the Oracle database. This streamlined communications stack allows for more efficient connectivity of Oracle servers when server-side Java procedures are being used.

Connections to the Oracle server are available directly through Java applications, Java applets, or via an application server such as Oracle9iAS. The main difference is that the application server acts as the client, providing communications to and from the Oracle server. JDBC is an interface that allows Java programs to interact with data stored in tabular form, such as in an Oracle database. Typically in this environment, an HTTP request is initiated at the client and sent to the application server.

The application server forwards the request to the appropriate database service for processing. Oracle Net serves as the mechanism for communication between the application server and the database.

HTTP is used to send the request to the application server and to receive the response from the application server.

A client can make a request to the Oracle database and interface with these components directly. Oracle Net must be configured on the server to accept and process these types of requests. Summary T here are several key components that are necessary to understand in order to succeed when you are networking in an Oracle environment.

The main responsibilities of the network administrator include determining the applications and type of connections that will be supported, the number of users and the locations from which they will be accessing the network, and the security issues involved in protecting sensitive information, such as single sign-on and data encryption.

In addition to being aware of their own responsibilities, the DBA needs to choose from the three basic types of network configurations when setting up their Oracle network: Because systems have evolved from the simpler single-tier architecture to the more complex n-tier architecture, which can include connections through middle-tier servers and the Internet, database administrators will most likely find themselves choosing between the two architectures that Oracle Net is an integral part of: Oracle Net manages the flow of information from client computers to Oracle servers and forms the foundation of all networked computing in the Oracle environment.

Oracle Net is comprised of a series of layers that make up the Oracle Net stack architecture. This architecture is based on the OSI model of networking and provides the basic building blocks of network interaction. Each layer in the Oracle Net stack is responsible for one or more networking tasks. Requests and responses are sent up and down the stack, which exists on both the client and the server.

In addition to the main network architecture that supports connections to an Oracle server, Oracle Net provides services that can be divided into five main categories: Connectivity solutions include support for multiple protocols, multiple operating systems, and Java and Internet. Directory Services provide an infrastructure to resolve Oracle service names through a centralized naming repository.

Accessibility support includes Heterogeneous Services and support for calling external procedures. Oracle Net also provides connectivity to Java stored procedures: This chapter provides the foundation of knowledge that you will need to understand when you are designing an Oracle network infrastructure.

The decisions you make about the network design have ramifications in terms of the scalability, security, and flexibility of your Oracle environment. When you understand the underlying network architecture and the network options available to you, you will be able to make informed choices when you are designing your Oracle network. You should be able to list the responsibilities of the database administrator with respect to network administration.

Can you define the basic network configuration choices and summarize the strengths and weaknesses of these options? Understand what Oracle Net is and the functionality it provides.

You should be able to define the five categories of functionality that Oracle Net provides and what functionality falls into each category. In addition, you should be able to define Oracle Advanced Security and know when to use it.

Be able to define the uses of the Heterogeneous Services and the situations in which these options are useful. Heterogeneous Services provide the ability to communicate with non-Oracle databases and services. Be able to define the Oracle Net stack architecture. This model divides the responsibility of conducting network transactions among various layers.

You should know the names and definitions of the various layers of the Oracle Net stack. You should have a basic understanding of the connection options Oracle provides from the Internet. This includes connections made via an application server and connections made directly to the Oracle server from a web browser. Key Terms Before you take the exam, be certain you are familiar with the following terms: All of the following are examples of networking architectures except: N-tier C.

Single-tier D. Two-tier E. All of the above are examples of network architectures. You manage one non-Oracle database and several Oracle databases. An application needs to access the non-Oracle databases as if it were part of the Oracle databases. What tool will solve this business problem? Choose the best answer.

Oracle Advanced Security B. Oracle Connection Manager C. Heterogeneous Services D. Oracle Net E. None of the above 3.

Which of the following is true about Oracle Net? It is not an option included in the Oracle Enterprise installation. It has an open API. It is never installed directly on a client workstation. A DBA wants to centrally administer all of the Oracle network services in a large Oracle9i installation with many network services. Which facility would best provide this functionality at minimal cost? Advanced Security B. Heterogeneous Services C. Oracle Shared Server D. Computer programming languages B.

Oracle Net connection tools C. Networking protocols D. Network programming languages 6. Which feature of Oracle Net best describes this statement: GUI tools integration B. Robust tracing and diagnostic tools C. Zero configuration on the client D. Network transport protocol support 7.

IPA C. GIOP D. Oracle Internet Directory 8. What is the standard that the Oracle Net communications stack is based on? OCI B. NPI C. OSI D. Application Layer B. Physical Layer C. Data Link Layer D. Network Layer What is the default name of the process that is used to make external calls via Oracle Net? IIOP is an example of which of the following? Tools to use for Oracle Net B. Oracle network integration utilities C.

Internet network protocol D. Portions of the Oracle Net stack Connection Manager provides which of the following? Multiplexing B. Cross protocol connectivity C. Network access control D. Which of the following is true about the OCI layer? It displays the graphical interface. Its datatype conversions are handled. It interfaces directly with the protocol adapters. It interfaces directly with the TTC layer. To which of the choices below does the following statement apply?

Proxy-based firewalls B. Filter-based firewalls C. Both types of firewalls D. Neither type of firewall When a connection is made via a Java applet, what type of driver is utilized? ODBC driver D. OCI driver A client workstation connects to a transaction server, which passes on requests to the Oracle database. This is a description of which of the following? Single-tier architecture B. N-tier architecture D.

Which Oracle Net networking product can be best described as middleware? Oracle Internet Directory B. Oracle Advanced Networking D. Oracle Shared Server Which of the following are characteristics of complex networks?

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Multiple protocols B. Diverse geographic locations C. Multiple operating systems D. Multiple hardware platforms E.

What is the preferred method of centralized naming in an Oracle9i environment? Oracle Names Server B. Directory Naming with Oracle Internet Directory Which of the following is an example of the ability to group connec- tions together? Protocol Interchange B. Network Access Control C.

Multiplexing D. Data Integrity checking E. All of these are examples of network connectivity configurations. Networking can be as simple as a dumb terminal connected directly to a server via a serial connection. It can also be as complex as an n-tier architecture that may involve clients, middleware, the Internet, and database servers. Oracle Advanced Security would not solve this application problem because it addresses security and not accessibility to non-Oracle databases.

Oracle Net would be part of the solution, but another Oracle Network component is necessary. Connection Manager would also not be able to accommodate this requirement on its own.

Heterogeneous Services is the correct answer because these services provide crossplatform connectivity to non-Oracle databases. Oracle Net is included in the Oracle Enterprise installation and works with a variety of protocols.

It also has a client and a server component. The only statement that is true about Oracle Net is that it has an open Applications Program Interface API , which means that third-party software can write to these specifications to interact directly with Oracle Net.

Advanced Security, Heterogeneous Services, and Oracle Shared Server would not provide a solution to this business need because none of these address the issue of centrally managing network services. The best solution to the problem is the Oracle Internet Directory because it would facilitate centralized naming.

Oracle Net allows for support of multiple protocols. The Physical Layer is responsible for sending the actual data bits across the network.

The other layers are all above this base layer. The default name of the external procedure process is extproc.In the next few sections, you will learn how to use the Oracle Net Manager to configure the server-side network files.

The c the string Public. Stop-based 2. Create a query to display the name and hire date of any employee hired after employee Davies. After entering a value for the substitution variable, click the OK button. Network interface NI sublayer The network interface sublayer provides a common interface on which the clients and servers can process functions.