BlueTooth Interview Questions and Answers
Question - 41 : - What is the total number of masters and slaves in a piconet?
Answer - 41 : - 1 Master and 7 Slaves.
Question - 42 : - Which method is used for Data transfer?
Answer - 42 : - Asynchronous Connectionless (ACL) is Data transfer method in Bluetooth.
Question - 43 : - What is RJ-45?
Answer - 43 : - RJ-45 stands for Registered Jack – 45. It is an 8-wire connector for connecting computer systems on to a LAN, especially Ethernets. These connections are similar in appearance to the ubiquitous RJ-11, which are used in connecting telephone equipment, with little more width.
Question - 44 : - Which technology is used to avoid interference in Bluetooth?
Answer - 44 : -
Blue tooth uses frequency hopping technology. In this technology, 79 hop frequencies are transmitted and received from 2402 to 2480 mhz. hopping in a pseudo random sequence at a rate of 1600 times in a second. Guassian frequency shift keying modulation is utilized with a maximum data transfer rate of 721 kbps. Bluetooth protocol stack is developed and TCP/IP imported layers are used in this technology.
Interference is being avoided by utilizing the frequency-hop(FH) spread spectrum technology. It is adaptable for low-power, low-cost radio implementations and also used in certain wireless LAN products.
The major advantage with this technology transmission is the high rate of 1600 hops / ps. Another advantage is, short packet length is also used by Bluetooth.
Question - 45 : - Define Bluetooth dongle?
Answer - 45 : -
Bluetooth dongle is a technology that enables a PC for point to multi-point friendly connectivity with other similar Bluetooth devices, like PDA, mobile phone. The devices enable the communication between devices within a range of 30 feet apprx.
Certain recent desktops and laptops are built-in with Bluetooth dongle to communicate. Bluetooth enables a single adapter to allow multiple devices for communicating with one system to another.
Question - 46 : - Define Bluetooth profiles?
Answer - 46 : -
Order to describe the way of implementing user models accomplishments, the profiles are developed. A number of user scenarios are described by the user models where Bluetooth performs the radio transmission. Profile stack describes the options in each protocol which are mandatory for each profile, and defines range of parameters for each protocol. The profiles are concerned for decreasing the risk of interoperability issues among various products of different manufacturers.
Question - 47 : - Can you please explain the difference between power classes in Bluetooth?
Answer - 47 : -
Device Power Class, Max Output Power (mW), Max Output Power (dBm), Expected Range
- Class 1, 100mW, 20dBm, 100m
- Class 2, 2.5mW, 4dBm, 10m
- Class 3, 1mW, 0dBm, 10cm
Question - 48 : - Describe LDAP and also define its uses?
Answer - 48 : -
Lightweight Directory Access Protocol is one of the directory service protocols. It runs over TCP/IP. LDAP directory services implements a client/server model. Directory data is available on one or more LDAP servers. The server responds with a pointer to another LDAP server.
Uses:
LDAP allows the users to access the information in the directory to change. Online telephone directories and email directories are some of the uses of LDAP. LDAP directory has utilities to modify, delete, and search the entries.
Question - 49 : - Can you please explain the difference between Bluetooth and Infrared?
Answer - 49 : -
Connectivity:
One-to-one connections are made by infrared devices, while Bluetooth devices can form when all the devices have identified themselves to each other.
Versatility:
Bluetooth devices could work together; where as infrared devices need to be specially designed for specific devices.
Range:
Class 3 Bluetooth devices works at about 30 feet; while infrared is rated at 3 feet.
Orientation:
Infrared devices are direct line-of-sight; where as Bluetooth devices could communicate even in times of separation by obstacles. Security: Bluetooth is less secure than infrared due to the omni directional nature; where as infrared signals could only be intercepted by a device.
Question - 50 : - What is LMP (Link Management Protocol)?
Answer - 50 : -
Multiple data links are combined for the formation of a single traffic engineering link, for the purpose of scale ability. The in-band messaging is not restricted by the management of TE links, but can be utilized by using out-of-band techniques.
The Link Management Protocol runs between a pair of nodes and is utilized for managing TE links. LMP is specifically used for maintaining control channel connectivity, verifying the physical connectivity of the data links, correlating the link property information, suppressing downstream alarms and localizing the link failures for protection/restoration purposes.