Interview Questions

- Fail-safe approach defines the level that divides the security such that it is safe even in case the system is failed.

- The fail safe approach doesn’t allow an attacker to take the advantage by breaking in the system and crashes out.

- This approach allows the web server to perform the routines even if the system runs out of the memory in case of any attack. 

- The system in attacks doesn’t skip the access to the control check or it doesn’t skip serving any document requested. 

- Fail safe approach can force the web server to run of the memory and have a DoS attack.

- A clustered index is a special type of index that reorders the way records in the table are physically stored. Therefore table can have only one clustered index.

- A non clustered index is a special type of index in which the logical order of the index does not match the physical stored order of the rows on disk. The leaf node of a non clustered index does not consist of the data pages. Instead, the leaf nodes contain index rows.

Oracle supports 3 transaction isolation levels: 

- Read committed (default)

- Serializable transactions

- Read only

unlink()-deletes the given file from the file system.
unset() -makes a variable undefined.

Basically there are many standards of Wi-Fi in the industry but some popular of them are 802.11a, 802.11b, 802.11g/n. With the support of these Wi-Fi protocols we can communicate/interact among the devices at the speed of 5Ghz to 2.4Ghz dual band communication.

If we have Wi-Fi nic card so firstly we have to install their drivers and after installation if we have Wi-Fi access point then we can see the signal strength in the right corner below just open that and find the access point to connect, if access point is configured with the security, type the key to connect and enjoy the service.

Wi-Fi is technically referred to as the 802.11 protocol. Over time, Wi-Fi has improved, giving rise to different variations of the protocol.

802.11a – This version operates at 54Mbps. It is considered as the favorite wireless LAN protocol for IP telephony.

The classloader is a subsystem of JVM that is used to load classes and interfaces.There are many types of classloaders e.g. Bootstrap classloader, Extension classloader, System classloader, Plugin classloader etc.

TTL is a value in data packet of Internet Protocol. It communicates to the network router whether or not the packet should be in the network for too long or discarded. Usually, data packets might not be transmitted to their intended destination within a stipulated period of time. The TTL value is set by a system default value which is an 8-bit binary digit field in the header of the packet. The purpose of TTL is, it would specify certain time limit in seconds, for transmitting the packet header. When the time is exhausted, the packet would be discarded. Each router receives the subtracts count, when the packet is discarded, and when it becomes zero, the router detects the discarded packets and sends a message, Internet Control Message Protocol message back to the originating host.

AWT are heavy-weight componenets. Swings are light-weight components. Hence swing works faster than AWT.