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The correct option is (C) DNS SPOOFING

Explanation: In DNS spoofing, also known as DNS cache poisoning, an attacker gets the valid CREDENTIALS from a victim by spoofing the intended RESOURCE, and tricking the victim to give his/her valid authorization credentials.

The CORRECT choice is (a) international data encryption algorithm

To elaborate: The IDEA was DESIGNED in 1991 by Xuejia Lai and James Massey. Before IDEA, PGP USED the cipher METHOD BassOmatic.

The CORRECT option is (b) email SECURITY

Explanation: PGP is an encryption method used in e-mail security to encrypt and decrypt the content of an e-mail transmitted over the internet. It makes sure that the MESSAGE cannot be stolen by other UNAUTHORIZED users.

Right answer is (b) wireless networks

To ELABORATE: The EXTENSIBLE Authentication Protocol (EAP) is an authentication protocol used to connect a network NODE to the INTERNET. It designed through EXTENDING the methods used by the Point-to-Point Protocol for authentication.

The correct answer is (a) DENIAL-of-service ATTACK

To explain: In a Denial of Service attack, the attacker won’t let the victims access the NETWORK by using a certain method that ensures that an essential network resource is UNAVAILABLE to the VICTIM. The methods that the attacker can use are vulnerability attack, bandwidth flooding and connection flooding.

The correct choice is (a) STATEFUL firewall and STATELESS firewall

Explanation: Most network layer firewalls can operate as stateful or stateless firewalls, creating two subcategories of the standard network layer firewall. Stateful firewalls have the advantage of being able to track packets over a period of time for greater analysis and accuracy — but they require more memory and operate more slowly. Stateless firewalls do not analyze past traffic and can be useful for systems where SPEED is more IMPORTANT than SECURITY, or for systems that have very specific and limited needs. For example, a computer that only needs to connect to a particular backup server does not need the extra security of a stateful firewall.

Right ANSWER is (b) packet filter

For explanation I would say: As you know, firewalls are available as hardware appliances, as software-only, or a combination of the two. In every case, the purpose of a firewall is to isolate your trusted internal network (or your PERSONAL PC) from the dangers of unknown resources on the Internet and other network connections that MAY be harmful. The firewall prevents unauthorized access to your internal, trusted network from OUTSIDE threats.

Correct CHOICE is (a) Entire IP packet

For explanation: In the tunnel mode, IPSEC ADDS control bits into the packets to encrypt the entire packet between the IPSec endpoints. Using encryption, it provides secure COMMUNICATION between the two endpoints.

The correct option is (b) network layer

Easy explanation: IPSEC is a set of protocols USED to provide AUTHENTICATION, DATA integrity and confidentiality between two machines in an IP network. In the TCP/IP model, it PROVIDES security at the IP layer i.e. the network layer.

Right answer is (b) Link State Packet

To ELABORATE: A Link State Packet is a packet created by a router that lists its neighboring NODES and routers in link state routing protocol. It is SHARED with other routers to find the SHORTEST path from a SOURCE to the destination.

The correct answer is (a) Reverse Path Forwarding

The explanation: Reverse Path Forwarding is a loop-free forwarding method for multi-cast routing in MODERN SYSTEMS. The method FOCUSES on forwarding the packet AWAY from the source IP in each iteration to make sure there is no loops.

The correct choice is (b) Loops

For explanation: In multicast routing, there is ONE sender and MANY receivers. So FLOODING is the most BASIC METHOD to forward packets to many receivers. The one issue with flooding is that it creates routing loops. One loop prevention method is that the routers will not send the packet to a node where the packet has been received before.

Right answer is (a) Graph

To elaborate: The Djikstra’s shortest path algorithm is the fastest among the ALGORITHMS for finding the shortest path in a graph. But it is a GREEDY method based algorithm so it does not guarantee the shortest path EVERY time.

Right option is (c) GUARANTEED

The best explanation: In Unicast routing, there is only SENDER and one receiver. So, if there is instability between three nodes, in which one is sender, one is receiver and one is the router in the PATH, there is no other path available for the packet and the STABILITY of the network is not guaranteed.

Right answer is (B) Security Measures

The best I can EXPLAIN: In host-specific routing, the ROUTE of the packet is defined based on the exact MATCH of the packet’s IP with the routing table entry of the host. It provides the best security for the packet as the packet is forwarded only to routers in the pre-defined path.

The correct choice is (d) Security

The best I can explain: The size of the routing table in the TECHNIQUE must be manageable for the NETWORK nodes i.e. it must not be too big. Security of the forwarding PACKET is the highest priority for a technique and must be high ENOUGH so that only authorized senders and receivers can access the packet’s CONTENT.

The correct choice is (c) Routing Table

Explanation: In the next-HOP forwarding method, the routing table of each router in the path contains the address of only the next hop in the path of PACKET. This method is SUITABLE for SHORT distances only.

The correct choice is (c) Forwarding

Easy explanation: Forwarding is done by the nodes in the path from SOURCE to destination, that are not the intended destination for the packet in ORDER to PASS the packet to the next node in the path. The destination machine does not FORWARD the packet to any other node.

Correct answer is (b) False

Best EXPLANATION: POST operation can cause DIFFERENT result so they are not idempotent. The DELETE and PUT operations are idempotent as they invoke the same result EVERY time they are called.

Correct answer is (B) True

The best explanation: In REST architecture, a REST Server SIMPLY provides ACCESS to resources and REST client accesses and presents the resources. It is popularly used because it MAKES efficient use of the bandwidth and can be cached for better performance and scalability.

The correct OPTION is (c) @PUT

The best I can explain: @PUT is the HTTP request that is USED to create resource and ALSO define a complete resource PATH. @POST may also be used to create a resource but it won’t define a resource path i.e. an accessing medium.

Correct option is (b) 201

For explanation: HTTP Status Code 201 MEANS CREATED, when a resource is successful created USING POST or PUT request. The code 200 means SUCCESS i.e. OK, code 204 means NO CONTENT, and the code 304 means NOT MODIFIED.

Correct ANSWER is (b) PRIVATE

To elaborate: Private directive indicates that resource is cachable by only client and server; no intermediary can cache the resource. But if we USE the public directive, it indicates that the resource MAY be cachable by any intermediary component.

The correct choice is (b) DELETE

Explanation: DELETE operation should be idempotent, means their result will always same no matter how MANY times these OPERATIONS are INVOKED. Also, the PUT operation is supposed to be idempotent.

Right answer is (a) HTTP

The best explanation: Restful web SERVICES make use of HTTP PROTOCOL as a medium of communication between CLIENT and server. The REST architecture was KNOWN as the HTTP object model back in the year 1994.

The correct choice is (b) Representational State Transfer

Explanation: REST stands for Representational State Transfer and is a software architecture STYLE in which the SERVER sends a REPRESENTATION of the state of the resource that it requests. It provides INTEROPERABILITY between the systems.

Correct choice is (c) 4 KB

The BEST I can explain: Each cookie can hold up to only 4 KB. In practice, browsers allow MANY more than 300 COOKIES total, but the 4 KB SIZE limit may still be enforced by some. Storage of a session has to be a minimum of 5MB.

Correct choice is (a) EncodeURIComponent()

For explanation: Cookie VALUES cannot include semicolons, COMMAS, or whitespace. For this reason, you may want to USE the core JAVASCRIPT global FUNCTION encodeURIComponent() to encode the value before storing it in the cookie.

Right choice is (B) SECURE

The best explanation: The FINAL cookie attribute is a boolean attribute named secure that specifies how cookie values are transmitted over the network. By default, cookies are INSECURE, which means that they are transmitted over a normal, insecure HTTP connection. If a cookie is marked secure, however, it is transmitted only when the browser and server are connected via HTTPS or another secure protocol.

The correct OPTION is (a) /

To ELABORATE: SETTING the path of a cookie to “/” gives scoping like that of localStorage and also specifies that the browser must transmit the cookie NAME and value to the server whenever it requests any web page on the site.

Right ANSWER is (d) Server

Easy explanation: The Cookie visibility SCOPE is configurable through cookie attributes path and domain. Domain attribute in the cookie is USED to SPECIFY the domain for which the cookie is sent. Path INCLUDES the Path attribute in the cookie to specify the path for which this cookie is sent.

Correct choice is (d) All of the mentioned

Explanation: sessionStorage, LOCALSTORAGE and Document path all are used to STORE data on the client-side. Each ONE has its own storage and expiration limit. Cookie VISIBILITY is scoped by the document origin as Local Storage and Session Storage are, and also by document path.

The correct CHOICE is (c) Max-age

Explanation: If you want a cookie to last beyond a single browsing session, you must tell the browser how long (in SECONDS) you would like it to retain the cookie by specifying a max-age attribute. A number of seconds until the cookie expires. A zero or negative number will kill the cookie IMMEDIATELY.

Correct choice is (d) Transient

To elaborate: Cookies are transient by default; the values they store LAST for the duration of the web browser session but are lost when the user EXITS the browser. While the browsing session is ACTIVE the cookie stores the user values in the user’s storage itself and accesses them.

The correct option is (a) cookie

The best explanation: The cookie property sets or returns all name/value pairs of cookies in the current document. There are no methods INVOLVED: cookies are queried, SET, and deleted by READING and writing the cookie property of the Document OBJECT USING specially formatted strings.

Right ANSWER is (B) Server SIDE programming

Explanation: Cookies were originally designed for server side programming, and at the LOWEST level, they are implemented as an extension to the HTTP protocol. They were introduced with the intention of providing a better user experience for the websites.

Correct option is (c) Both Datagram Socket & Datagram PACKET

Explanation: Datagram is BASICALLY some information TRAVELLING between the sender and the receiver, but there is no guarantee of its content, arrival or arrival time. Datagram Socket, Datagram Packet are USED for connection-less socket programming, while Server Socket is used for connection-oriented socket programming.

Correct OPTION is (a) Public STRING get Hostname()

The best explanation: In Inet Address CLASS public String getHostname() method RETURNS the host name of the IP Address. The getHostAddress() method returns the IP address of the given host name.

The correct option is (a) True

To elaborate: The FLUSH () method of PRINT STREAM CLASS FLUSHES any un cleared buffers in memory.

Correct OPTION is (B) IP Address

Best explanation: The java.net.InetAddress class represents IP Address of a particular specified host. It can be USED to RESOLVE the host name from the IP address or the IP address from the host name.

The CORRECT choice is (c) PROTOCOL

The best explanation: TCP, FTP, Telnet, SMTP, POP etc. are examples of Protocol. Out of them, TCP is a transport layer protocol and FTP, TELNET, SMTP and POP are application layer PROTOCOLS.

Correct answer is (a) True

The best explanation: Datagram is BASICALLY some information travelling between the sender and the receiver, but there is no guarantee of its content, ARRIVAL or arrival time. A Datagram SOCKET CLASS object is created to make a datagram CONNECTION between the server and the client.

The correct ANSWER is (a) True

To elaborate: The URL Connection CLASS can be used to READ and write data to the SPECIFIED resource referred by the URL. A connection to the URL is initialized by the OpenConnection() METHOD of the class.

Correct ANSWER is (c) Both IP ADDRESS of SERVER & Port number

The explanation is: The client in socket PROGRAMMING must know IP address of Server as it has to use that IP address in order to initialize the socket class constructor. That is how the client requests a connection to the server.

Correct option is (b) Public Socket accept ()

To explain I would say: The Public socket accept () method is used by the ServerSocket CLASS to accept the connection request of exactly ONE client at a time. The client requests by initializing the socket OBJECT with the servers IP address.