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The correct choice is (d) Static ports

Easiest explanation: IANA divided port numbers into three ranges i.e., Well-known, Registered and DYNAMIC ports. Well-known port numbers RANGE from 0 to 1023, registered port numbers are from 1024 to 49151 and dynamic port numbers are from 49152 to 65535.

Right ANSWER is (d) 0 and 65,535(16-bit)

To EXPLAIN: Port numbers are 16-bit integers between 0 and 65,535. They are an interface for the IMPLEMENTATION of PROCESS to process delivery for the TRANSPORT layer.

Correct answer is (B) Port number

Explanation: MULTIPLE processes on DESTINATIONS are identified by a transport layer address also called as port number. The IP address along with the port number is called the socket address.

Correct answer is (a) CLIENT/Server

The explanation is: The most COMMON method used for this communication is Client/Server. The client requests a service through a PARTICULAR PORT number to the port of the server using its socket address. Then the server RESPONDS by giving the requested service to the client port.

The correct option is (C) Transport layer

Easiest explanation: The transport layer is responsible for process-to-process DELIVERY, error control and FLOW control. It provides an INTERFACE for the implementation of process to process delivery through ports. There are 65,535 port numbers.

Right CHOICE is (d) June 6, 2012

For explanation I would say: IPv6 is the latest VERSION of the Internet Protocol released on 6^th June 2012. An IPv6 ADDRESS is 128 bits LONG. Therefore, 2^128 i.e. 340 undecillion addresses are possible in IPv6.

Correct choice is (b) Two COLONS (::) are used to represent successive HEXADECIMAL fields of zeros

For EXPLANATION I would say: In order to shorten the written length of an IPv6 address, successive fields of zeros may be replaced by double colons. In trying to shorten the address further, leading zeros may also be removed. Just as with IPv4, a SINGLE DEVICE’s interface can have more than one address; with IPv6 there are more types of addresses and the same rule applies. There can be link-local, global unicast, and multicast addresses all assigned to the same interface.

Correct choice is (a) Prefix type

Easiest explanation: Prefix is the BITS in the IP address which are placed in leftmost position. A NETWORK prefix in IPV6 is GIVEN by a CIDR format-liked number at the end of the address.

Correct option is (b) Loopback ADDRESS

Explanation: In SUBCATEGORIES of reserved address in IPV6, address that is USED by a host to test itself without going into NETWORK is called loop back address. IPv6 loopback address is 0000:0000:0000:0000:0000:0000:0000:0001. IPv4 loopback address is 127.0.0.1. It’s a reserved address.

Correct CHOICE is (c) Isolated subnet

To explain I would say: Isolated subnet is very huge SHARING network area in this link local ADDRESS of local addresses is USED. A link local address can be configured on any subnet with the prefix “FE80::”.

Correct choice is (a) 96 to 127

The explanation is: TEREDO is a TECHNIQUE through which gives the possibility for full IPv6 network connectivity to IPv6 capable hosts which are currently on an IPv4 network. Bits 96 to 127 in the datagram represents OBFUSCATED 1Pv4 address of the IPv4 network.

Correct ANSWER is (b) Tunneling

For explanation: The IPv4 ROUTERS can form a tunnel in which at the sender’s side, the IPV6 datagram is encapsulated in to IPv4, and at the RECEIVER’s side of the tunnel, the IPv4 packet is stripped and the IPv6 packet is SENT to the receiver.

The CORRECT CHOICE is (a) 96 to 127

The best I can explain: Teredo is a TECHNIQUE through which gives the possibility for full IPv6 network connectivity to IPv6 capable HOSTS which are CURRENTLY on an IPv4 network. Bits 96 to 127 in the datagram represents obfuscated 1Pv4 address of the IPv4 network.

Correct answer is (C) node has both IPv4 and IPv6 support

The best I can EXPLAIN: Dual-stack is one of the approaches used to support IPv6 in already existing SYSTEMS. ISPS are using it as a method to TRANSFER from IPv4 to IPv6 completely eventually due to the lower number of possible available addresses in IPv4.

The correct CHOICE is (a) Hop LIMIT

The explanation: The Hop limit VALUE is decremented by one by a router when the datagram is forwarded by the router. When the value BECOMES zero the datagram is discarded. The field is 8-bits wide, so an IPv6 packet can live up to 255 router hops only.

Correct choice is (d) Anycast ADDRESS

To explain I would say: There is an anycast address in IPV6 which allows SENDING MESSAGES to a group of devices but not all devices in a network. Anycast address is not standardized in IPv4.

Correct option is (c) ToS field

To explain: The traffic class field is used to specify the PRIORITY of the IP PACKET which is a similar functionality to the TYPE of Service field in the IPv4 header. It’s an 8-bit field and its VALUES are not defined in the RFC 2460.

The correct choice is (B) 128 bits

For explanation: An IPv6 address is 128 bits long. Therefore, 2128 i.e. 340 undecillion addresses are possible in IPv6. IPv4 has only 4 billion possible addresses and IPv6 would be a BRILLIANT alternative in CASE IPv4 runs out of possible new addresses.

The correct option is (d) Class F

The EXPLANATION: Class F is not a class of IP addressing. There are only FIVE CLASSES of IP addresses: Class A (0.0.0.0 to 127.255.255.255), Class B (128.0.0.0 to 191.255.255.255), Class C (192.0.0.0 to 223.255.255.255), Class D (224.0.0.0 to 239.255.255.255), and Class E (240.0.0.0 to 255.255.255.255).

Correct choice is (C) IP Addressing

Explanation: Network addresses are a very important CONCEPT of IP addressing. The first address in a block is used as network address that represents the organization. The network address can be FOUND by AND’ing any address in the block or class by the default mask.

The correct answer is (c) Wasted

Easiest explanation: In classful addressing, a LARGE part of AVAILABLE addresses are wasted. Thus to solve this classful addressing is replaced with CLASSLESS addressing where ONE can reserve the number of IP addresses required by modifying the CIDR value and make sure that not many addresses are wasted.

Correct answer is (c) Organization

To explain: First address in a block is USED as NETWORK address that represents the organization. The network address can be FOUND by AND’ing any address in the block by the default mask. The LAST address in a block represents the broadcast address.

Correct choice is (a) Classless Addressing

Easiest EXPLANATION: Classful addressing is replaced with classless addressing as a large RATIO of the available addresses in a class in calssful addressing is wasted. In classless addressing, ONE can reserve the NUMBER of IP addresses REQUIRED by modifying the CIDR value and make sure that not many addresses are wasted.

Correct OPTION is (B) BLOCKS

Best explanation: In classless addressing, there are no classes but addresses are still granted in blocks. The total number of addresses in a block of classless IP addresses = 2^(32 – CIDR_value).

Right choice is (a) Offset

Easiest EXPLANATION: The Fragment Offset field SPECIFIES where the fragment fits in the original DATAGRAM. The offset of the first fragment will always be 0. The size of the field (13 bits) is 3-bits shorter than the size of the total LENGTH field (16 bits).

Right answer is (d) All of the mentioned

Best explanation: FRAGMENTATION makes the implementation of the IP protocol complex and can ALSO be exploited by attackers to create a DOS ATTACK such as a TEARDROP attack. Fragmentation won’t be required if the transport layer protocols PERFORM wise segmentation.

The correct option is (b) Offer RELIABLE service

Easy explanation: IP does not provide reliable DELIVERY service for the data. It’s DEPENDENT upon the transport LAYER protocols like TCP to offer reliability.

Correct OPTION is (a) offset

Easiest EXPLANATION: The Fragment Offset field specifies where the fragment fits in the original DATAGRAM. The offset of the FIRST fragment will always be 0. The size of the field (13 bits) is 3-bits shorter than the size of the total LENGTH field (16 bits).

Correct option is (b) offer reliable service

The BEST explanation: IP does not PROVIDE reliable delivery service for the data. It’s dependent UPON the transport layer protocols like TCP to offer RELIABILITY.

The correct choice is (a) 0

To explain I would say: The FLAG FIELD in the IP header is used to control and identify the FRAGMENTS. It contains three BITS: reserved, don’t fragment and more fragments. If the more fragments bit is 0, it means that the fragment is the last fragment.

Right answer is (c) ICMP messages

Explanation: Data FIELD USUALLY has transport layer segments, but it can also carry ICMP messages. SMTP is an APPLICATION layer protocol. First it must go through the transport layer to be converted into TCP segments and then it can be inserted into IP PACKETS.

Correct choice is (b) UDP

Explanation: The protocol field enables the demultiplexing feature so that the IP protocol can be used to carry payloads of more than ONE protocol type. Its most used VALUES are 17 and 6 for UDP and TCP RESPECTIVELY. ICMP and IGMP are network layer PROTOCOLS.

Correct choice is (c) 10

The EXPLANATION: TTL stands for Time to Live. This FIELD specifies the life of the IP packet based on the number of hops it MAKES (Number of routers it goes through). TTL field is decremented by one each time the DATAGRAM is processed by a router. When the value is 0, the packet is AUTOMATICALLY destroyed.

Correct option is (a) Error reporting

To explain I would SAY: The Internet Protocol is the networking protocol which establishes the internet by relaying datagrams across network boundaries. ICMP is a supporting protocol for IP which HANDLES the Error Reporting functionality.

The correct choice is (d) CSS

The best I can EXPLAIN: CSS ALONE cannot be used to generate dynamic web pages as it does not provide MANY event handling functions. It can be used along with JavaScript to generate dynamic web pages which are visually compelling.

The correct CHOICE is (a) sent from a website and STORED in user’s web browser while a user is browsing a website

To ELABORATE: A web cookie is a small piece of data sent from a website and stored in user’s web browser while a user is browsing the website and is used to remember stateful information about the user’s OPERATIONS on the website. This can help the website provide a better browsing experience to the user.

The correct answer is (c) UNIFORM resource locator

The BEST I can EXPLAIN: The Uniform Resource Locator is a locator for the resource to be located by HTTP on the World Wide WEB. The URL is DERIVED from the Uniform Resource Identifier.

Right answer is (a) generate executable files from WEB content by web SERVER

To EXPLAIN I would say: CGI is an interface through servers can run execute console-based executable files on a web server that generates dynamic web PAGES. A CGI script executes only when a request is made. The script then generates HTML.

Right answer is (d) all of the mentioned

The BEST EXPLANATION: A web browser is an application PROGRAM that is used to access the World Wide Web resources, applications and websites. Some examples of web BROWSERS are Google Chrome, Internet Explorer and SAFARI.

Correct ANSWER is (b) generates on demand by a program or a request from browser

To ELABORATE: A dynamic web page provides DIFFERENT content EVERY time the user opens it based on some events like NEW additions or time of the day. Languages such as JavaScript are used to respond to client-side events while languages such as PHP as used to respond to server-side events.