Question: What Is Logical And Physical File?

Is IP address logical or physical?

Logical vs.

An IP address is a logical address that is assigned by software residing in a server or router (see DHCP).

The physical address is built into the hardware (see MAC address)..

How do I create a file in as400?

Creating Physical and Logical files in AS400Create a Physical File. To create a physical database file, enter your source statements in a DDS source file member. … Create a Physical File With Key Fields. Let’s modify this file definition to add key fields. … Create a Logical File To Resequence Order of Records. … Create a Logical File To Select and Resequence Records.

What is a logical file system?

The logical file system is the level of the file system at which users can request file operations by system call. … Each set of predefined operations implemented constitutes a virtual file system. As such, a single physical file system can appear to the logical file system as one or more separate virtual file systems.

What is the difference between a physical and logical network diagram?

Logical network diagrams focus in on how traffic flows across the network, IP addresses, admin domains, how domains are routed, control points, and so on. … A physical network diagram will, ideally, show the network topology exactly as it is: with all of the devices and the connections between them.

What is an example of a file?

A file is an object on a computer that stores data, information, settings, or commands used with a computer program. … For example, the picture is an icon associated with Adobe Acrobat PDF files.

What are the structures used in file system implementation?

A directory structure ( per file system ), containing file names and pointers to corresponding FCBs. UNIX uses inode numbers, and NTFS uses a master file table. The File Control Block, FCB, ( per file ) containing details about ownership, size, permissions, dates, etc.

What is access path in as400?

Ü Access path Access path describes the order in which records are to be read. Access paths can be kept on the system permanently (such as physical or logical file) or temporarily. OPNQRYF command may create a temporary access path for use one time, and then discard the access path.

What is record format in as400?

1. A “record format” is a named structure that is used for device file I/O. It contains descriptions of each column in the ‘record’ (or ‘row’). The specific combination of data types and sizes and the number and order of columns is hashed into a value that is known as the “record format identifier”.

Why are both physical and logical topologies necessary?

When a problem arises, I.E. a link is down, by simply looking at the physical layout, we are able to quickly identify where the problem is located, allowing us to quickly resolve it. Having a visual view of a logical and physical network also helps identify possible security problems.

What is the physical or logical arrangement of a network?

topologyThe physical or logical arrangement of network is called topology. Topology is the network of interconnection elements.

What is the difference between logical and physical?

The logical address is used like a reference, to access the physical address. The fundamental difference between logical and physical address is that logical address is generated by CPU during a program execution whereas, the physical address refers to a location in the memory unit.

What is logical file in as400?

A logical file is a database file that describes how data records contained in one or more physical files are presented to a program. The logical file does not contain data records.

What happens if 2 devices have the same MAC address?

If two devices have the same MAC Address (which occurs more often than network administrators would like), neither computer can communicate properly. … Duplicate MAC Addresses separated by one or more routers is not a problem since the two devices won’t see each other and will use the router to communicate.

Is logical address same as IP address?

Every network device has two types of addresses, one called the logical address — in most cases this is the IP address — and the other one being the physical address — also known as the MAC address. The IP address is an address bound to the network device, i.e., computer, via software.

What is basic file system?

A file is a container that holds information. Most of the files you use contain information (data) in some particular format–a document, a spreadsheet, a chart. The format is the particular way the data is arranged inside the file. The format of a file is known as its data type. … Each data type has a different icon.

What is meant by logical address?

In computing, a logical address is the address at which an item (memory cell, storage element, network host) appears to reside from the perspective of an executing application program. A logical address may be different from the physical address due to the operation of an address translator or mapping function.

What are physical and logical topologies?

A logical topology is how devices appear connected to the user. A physical topology is how they are actually interconnected with wires and cables.