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The correct choice is (a) device

For explanation I WOULD SAY: XMPP creates a device IDENTITY ALSO called a Jabber ID. In MQTT, identities are created and managed separately in BROKER implementations.

The correct CHOICE is (a) True

The EXPLANATION is: YES, You can PASS a user name and password with an MQTT packet in V3.1 of the PROTOCOL.

Correct CHOICE is (c) Andy Stanford-Clark

Best explanation: MQTT is created by Andy Stanford-Clark in It was ORIGINALLY DEVELOPED by IBM and is now an OPEN standard.

The correct answer is (a) True

Explanation: The nodes have 8-bit MICROCONTROLLERS with SMALL AMOUNT of ROM and RAM, while constrained network such as IPv6 over Low-power Wireless Personal AREA Network OFTEN high packet error rates and a typical throughput of 10s of kbit/s.

The correct answer is (c) 2

The explanation is: Both asynchronous multiprocessor protocols, the idel line and the address bit microprocessor MODE allow efficient DATA transfer between MULTIPLE communication SYSTEMS.

Right CHOICE is (d) 9600bits/sec

To explain: The 8250 UART has ONE character BUFFER for the receiver and the transmitter each, which meant that communications software performed poorly at speed above 9600bits/sec, ESPECIALLY it operating under a multitasking system or if handling interrupts from disk controllers.

Right option is (B) I2C protocol

To EXPLAIN I would say: UART(Universal Asynchronous Receiver/Transmitter) is a SMALL, efficient communication device, similar to I2C.

Correct answer is (a) MAC address

The best explanation: Along with an IP address there is also a hardware address. Typically it is tied to a key connection device in your computer called the NETWORK INTERFACE card. Every NIC has a hardware address that’s KNOWN as MAC, for Media Access Control.

The CORRECT choice is (b) UDP

The EXPLANATION is: TCP, not UDP, provides reliable end to end communication, i.e. error recovery by MEANS of error detecting code and automatic REPEAT request PROTOCOL.

The correct CHOICE is (a) True

Explanation: IP is connectionless, is that a DATA packet can travel from a sender to a receiver WITHOUT the RECIPIENT having to send an acknowledgment connection-oriented protocols exits at other, higher layers of the OSI model.

Correct OPTION is (c) Internet Relay Chat

Easiest explanation: The XMPP extension for MULTI user chat can be seen a COMPETITOR to Internet Relay Chat, although IRC is far simpler, has far fewer FEATURES, and is far widely used.

Correct OPTION is (c) Sensors and Wi-Fi

Easy EXPLANATION: Following are the key components of a M2M system.

Sensors

RFID (Radio Frequency IDENTIFICATION)

Wi-Fi

Autonomic COMPUTING.

The correct ANSWER is (a) WEB Transfer

The best I can explain: The CoAP is a specialized web transfer protocol for use with CONSTRAINED nodes and constrained networks.

The correct CHOICE is (d) MULTI master, multi slave

To elaborate: I2C pronounced as I-squared-C, is a multi master, multi salve. It is typically used for attaching lower-speed peripheral IC’s to processors and micro controllers in short DISTANCE, INTRA band COMMUNICATION.

Right choice is (a) True

Explanation: In IDLE LINE MULTIPROCESSOR mode, a precise idle period can be GENERATED to create efficient address CHARACTER identifiers.

Right choice is (b) RS232C

For explanation: RS232C is a long established standard (“C” is the current version) that DESCRIBES the physical interface and protocol for relatively LOW speed serial data COMMUNICATION between computers and relates devices.

Right option is (b) True

To elaborate: MAC ADDRESSES are formed ACCORDING to the RULES of one of three numbering name SPACES managed by the INSTITUTE of Electrical and Electronics Engineers(IEEE).

Correct choice is (b) Variable Length SUBNET MASKING

The explanation is: The class system of the address SPACE was replaced with CLASSLESS Inter – Domain Routing in 1993. CIDR is based on variable length Subnet Masking to ALLOW allocation and routing based on arbitrary length prefixes.

Right OPTION is (b) 128 bits

The explanation is: Because of the growth of the Internet and the DEPLETION of available IPV4 address, a new version of IP(IPV6), using 128 nits for the IP address, was DEVELOPED in 1995, and standardized as RFC 2460 in 1998. IPV6 deployment has been ongoing since the mid 2000s.

Correct CHOICE is (d) Patterns

For explanation: There are commonly reoccurring problems that occur in the design and IMPLEMENTATION of communication protocol and can be addressed by patterns from SEVERAL different pattern languages: Pattern Language for APPLICATION Level Communication Protocol etc.

The correct option is (C) Transport protocols

Easiest EXPLANATION: Above the network layer, we FIND TCP and UDP, the two transport protocols. TCP is used for most of our human INTERACTIONS with the web. UDP is also BETTER suited for real-time data applications such as voice and video.

Right answer is (c) Routing Information Protocol

Explanation: The Routing Information Protocol is one of the OLDEST distance vector routing protocols which EMPLOY the hop COUNT as a routing METRIC.

Correct option is (B) 100 kbit/s

For EXPLANATION: There are several operating modes for I2C communication. All are COMPATIBLE in that the 100 kbit/s STANDARD MODE is always used.

The correct answer is (a) high to low

To explain I would say: SDA is having a high to low transition when the clock line SCL is high. Under normal CIRCUMSTANCES this does not happen as you can see in the subsequent clock PULSES that the data line is STABLE in one STATE, EITHER high or low when the clock line is high.

The correct option is (b) Underrun ERROR

To explain: An Under RUN error occurs when UART transmitter has completed sending a character and the TRANSMIT buffer is empty. In asynchronous mode this is treated as an indication that no data remains to be TRANSMITTED.

Right answer is (c) SPIUART

Best EXPLANATION: WD1402A is the FIRST single chip UART on general sale. INTRODUCED about 1971. COMPATIBLE chip included the Fairchild TR1402A and the general instruments AY-5-1013.

Right option is (a) Web chat

Easy EXPLANATION: There are MANY services PROVIDED by application layer:

1. SIMPLE mail transfer protocol

2. File transfer

3. Web transfer

4. Web chat etc.

Right option is (a) True

The best I can EXPLAIN: XMPP features such as FEDERATION across domains, public/subscriber, authentication and its security EVEN for mobile endpoints are being used to implement the INTERNET of THINGS.

Correct ANSWER is (d) MAC

To explain: On wireless NETWORKS, a process called MAC filtering is a security measure to prevent unwanted network ACCESS by hackers and intruders. In MAC ADDRESS filtering, the router is configured to accept traffic only from specific MAC addresses.

The CORRECT answer is (B) TCP

The explanation: The original and native transport protocol for XMPP is Transmission Control Protocol (TCP), USING open ENDED XML stream over long-lived TCP connections.

Correct choice is (c) SERVICE layer

To explain: In intelligent NETWORK and cellular network, service layer is a conceptual layer within a network service provider architecture. CoAP is a service layer PROTOCOL that is INTENDED for use in resource-constrained internet devices, such as wireless SENSOR network nodes.

Correct answer is (a) True

The best explanation: eSPI SLAVES are allowed to use the eSPI master as a PROXY to PERFORM FLASH operations on a standard SPI flash memory slave on behalf of the requesting eSPI slave.

The CORRECT option is (a) Synchronous DATA Link Control

The explanation is: Synchronous Data Link Control synchronous link LAYER protocols, which were with synchronous voice frequency modems. These protocols were DESIGNED to make the best use of bandwidth when modems were ANALOG devices.

Right choice is (b) END user

The explanation: In perception layer SENSOR networks are deployed on VARIOUS locations. Network layer CONTAINS Wireless or wired link. while APPLICATION layer interacts directly with the end user.

The correct option is (a) Automatic Repeat Request

The explanation: TCP, not UDP, provide end to end communication, i.e. error recovery by MEANS of error detecting code and automatic repeat request protocol. The ARQ protocol ALSO provides FLOW control, which may be COMBINED with congestion avoidance.

Right choice is (d) DATAGRAMS

The explanation is: UDP is a very simple PROTOCOL, and does not PROVIDE virtual circuits, nor reliable communication, deleting these functions to the application PROGRAM. UDP PACKETS are called datagrams, rather than segments.

The correct CHOICE is (d) Routers, Bridges and Switches

The explanation is: This layer contains hardware DEVICES such as routers, bridges, firewalls, and switches, but it actually creates a logical IMAGE of the most efficient communication ROUT and implements it with a PHYSICAL medium.

Correct CHOICE is (a) Third level

Easiest EXPLANATION: The NETWORK layer is the third level of the OPEN system interconnection model and the layer that provides data routing paths for network communication.

Right choice is (b) Flow control

The EXPLANATION: Devices at each end of a network connection often have no WAY of knowing each other’s capabilities in terms of data throughput and can THEREFORE send data faster than the receiving devices is able to buffer or process it. In these cases, buffer overruns can cause COMPLETE communication breakdowns.

The correct ANSWER is (d) HTTP

To explain: FINALLY, HTTP/2 INTRODUCES the notion of server PUSH. Concretely this means the server can provide content to clients without having to wait for them to send a REQUEST.

Correct option is (d) More pins

Easiest explanation: REQUIRES more pins on IC PACKAGE than I2C, EVEN in the THREE wire VARIANT.

Correct answer is (a) No START and stop bits

Best explanation: As we don’t have start and stop bits, so the DATA can be STREAMED continuously WITHOUT interruption.

Correct choice is (a) METHOD

Explanation: HTTP is a request/ response protocol where CLIENTS request information from a server and the server responds to these requests accordingly. A request is MADE up of a method, a resource, some headers, and some OPTIONAL content.