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Transport Layer

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  Transport Layer Introduction  The transport layer is a 4 th  layer from the top. The main role of the transport layer is to provide the communication services directly to the application processes running on different hosts. The transport layer provides a logical communication between application processes running on different hosts. Although the application processes on different hosts are not physically connected, application processes use the logical communication provided by the transport layer to send the messages to each other. The transport layer protocols are implemented in the end systems but not in the network routers. A computer network provides more than one protocol to the network applications. For example, TCP and UDP are two transport layer protocols that provide a different set of services to the network layer. All transport layer protocols provide multiplexing/demultiplexing service. It also provides other services such as reliable data transfer, bandwidth guarantees

Locality

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  Locality of reference   Locality of reference refers to the tendency of the computer program to access the same set of memory locations for a particular time period. The property of Locality of Reference is mainly shown by loops and subroutine calls in a program. What is 'the principle of locality'? - It is a term for the phenomenon in which the same values or related storage locations are frequently accessed. - It is also known as the locality of reference. - The next most data items or instruction is the closest to the current data item or instruction. - For example, a block in a file may be the closest one that is needed next. The OS can read the next block before its need and made available it on hand at the time of issuing the actual read request.   There are two types of principle of locality: 1. Temporal locality 2. Spatial locality Temporal locality This type of optimization includes bringing in the frequently accessed memory references to a nearby memory location for

Lock Conversion

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  Introduction to Lock Based Protocols in DBMS The DBMS houses data that can interact with one another and can be manipulated at any given instant. In a few scenarios, there is a possibility of more than one user trying to access a certain data item at the same time creating a concurrency. Thus, a need arises to deal with the said concurrency to handle the simultaneous execution of tractions among the multiple databases in the picture. One such method is termed as Lock Based Protocols. In this topic, we are going to learn about Lock Based Protocols in DBMS. Lock Based Protocols eliminate the shortcomings caused by the concurrency access in DBMS by providing the required isolation to the tractions involved within the DBMS. This article tends to provide an insight on Lock Based Protocols in DBMS What is Lock Based Protocols in DBMS? Hundreds of transactions happen each moment. Consider booking a movie ticket in your favorite cinemas, chances are two users will try to book the same seat u