N/W ( Tutorials II )

What Is Network A network is a group of computers or nodes connected together. They are connected with each other by communication paths. Types of Networks: LAN – Local Area Network connects a group of nodes covering a small physical area. LAN’s are most commonly seen in offices, building etc. LAN’s enable higher transfer rate of data, smaller coverage of area and hence less wiring. WAN – Wide Area Network connects a group of nodes covering...

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IP, TCP and UDP In Networking

Explain IP, TCP and UDP TCP – Transmission control Protocol is used to establish communication between nodes or networks and exchange data packets. It guarantees delivery of data packets in the order they were sent. Hence it is most commonly used in all applications that require guaranteed delivery of data. It can handle both timeouts (if packets were delayed) and retransmission (if packets were lost). The stream of data is transmitted in segments....

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7 Layers Of OSI

Explain the 7 Layers of OSI Layer 1: Physical layer It represents all the electrical and physical specifications for devices.  Layer 2: Data link layer It provides the functional and procedural means to transfer data between network entities and to detect and possibly correct errors that may occur in the Physical layer. Layer 3: Network layer The Network layer provides the functional and procedural means of transferring...

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N/W ( Tutorials I )

What Is LAN LAN is a computer network that spans a relatively small area. Most LANs are confined to a single building or group of buildings. However, one LAN can be connected to other LANs over any distance via telephone lines and radio waves. A system of LANs connected in this way is called a wide-area network (WAN). Most LANs connect workstations and personal computers. Each node (individual computer) in a LAN has its own CPU with which it...

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PHP ( Tutorials V )

Type Of Juggle In PHP Type Juggling means dealing with a variable type. In PHP a variables type is determined by the context in which it is used. If an integer value is assigned to a variable, it becomes an integer. E.g. $var3= $var1 + $var2 Here, if $var1 is an integer. $var2 and $var3 will also be treated as integers.   Difference Between Include And Require Require () and include () are the same with respect to handling failures....

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PHP ( TutorialsIV )

How can we increase the execution time of a php script Default time allowed for the PHP scripts to execute is 30s defined in the php.ini file. The function used is set_time_limit(int seconds). If the value passed is ‘0’, it takes unlimited time. It should be noted that if the default timer is set to 30 sec and 20 sec is specified in set_time_limit(), the script will run for 45 secs. How to set cookies in PHP  Cookies are often...

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Functions For IMAP In PHP

IMAP is used for communicate with mail servers. It has a number of functions. Few of them are listed below: Imap_alerts – Returns all the imap errors occurred Imap_body – Reads the message body Imap_check – Reads the current mail box Imap_clearflag_full – Clears all flags Imap_close – close and IMAP stream Imap_delete – Delete message from current mailbox Imap_delete_mailbox – Deletes a mailbox Imap_fetchbody – Fetches...

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Different types of errors in PHP

Different types of Errors are: E_ERROR: A fatal error that causes script termination E_WARNING: Run-time warning that does not cause script termination E_PARSE: Compile time parse error. E_NOTICE: Run time notice caused due to error in code E_CORE_ERROR: Fatal errors that occur during PHP's initial startup (installation) E_CORE_WARNING: Warnings that occur during PHP's initial startup E_COMPILE_ERROR: Fatal compile-time errors...

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Difference Between $message and $$message In PHP

Explain the difference between $message and $$message. $message is used to store variable data. $$message can be used to store variable of a variable. Data stored in $message is fixed while data stored in $$message can be changed dynamically. E.g. $var1 = ‘Variable 1’ $$var1= ‘variable2’ This can be interpreted as $ Variable 1=‘variable2’; For me to print value of both variables, I will write $var1 $($var1) Persistent Cookie Cookies...

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