SFWRTECH 3IT3: Physical & Data Link Layers

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What is the primary function of the Physical Layer in the OSI model?

Establishes/terminates a connection to the medium, participates in resolving contention/flow control, and modulates digital data into signals suitable for transmission.

What type of physical media is capable of carrying broadband services, such as high-frequency signal transmission?

Coaxial cable

What are the three main components of the Data Link Layer in the OSI model?

IEEE 802.2 Logical Link Control (LLC), IEEE 802.3 CSMA/CD Access Method, and Media Access Control (MAC) Addresses

What type of device is responsible for repeating signals in a network, and is an example of a Layer 1 device?

Repeater Signup and view all the answers

What is the term for the process of converting digital data into signals suitable for transmission over a physical medium?

Modulation Signup and view all the answers

What is the term for the process of resolving contention and controlling the flow of data in a network?

Flow control Signup and view all the answers

What is the maximum distance supported by Multi-mode Optical fibre for 1 Gbps Ethernet?

550 metres Signup and view all the answers

What frequency band is used by Bluetooth and 802.11b/g/n/ax/be Wi-Fi?

2.4 GHz Signup and view all the answers

What is the purpose of WiMAX technology?

To deliver 'last mile' broadband services Signup and view all the answers

What is the primary difference between isotropic and directional antennas?

Direction of transmission power Signup and view all the answers

What is the spectrum range of WiMAX technology?

2-66 GHz Signup and view all the answers

What type of antenna is most suitable for multiple receivers?

Omnidirectional (isotropic) antenna Signup and view all the answers

What type of connector is often used in conjunction with fibre connectors for higher interface speeds (10+ Gbps) and greater distances?

SFP+ Signup and view all the answers

What is the purpose of line codes in digital transmission?

To tune the code to the properties of the channel and encode the digital signal into a pattern. Signup and view all the answers

What type of connector is characterized by a simple, push-pull connector that is commonly used in data networking applications?

LC (Lucent Connector) Signup and view all the answers

What is the name of the RJ-45 connector pinout configuration that is typically used for 10BaseT, 100BaseTX, and 1000BaseT Ethernet connections?

T568A or T568B Signup and view all the answers

What type of connector is commonly used for coaxial cable connections and is characterized by a Bayonet-style mount?

BNC Signup and view all the answers

What is the name of the type of fibre-optic connector that is characterized by a straight tip and is often used in simplex applications?

ST (Straight Tip) connector Signup and view all the answers

What is the main benefit of using line coding in Ethernet, apart from synchronizing the clock signal?

Assisting in error detection Signup and view all the answers

How does the 4B5B line coding scheme map groups of bits into symbols?

Maps groups of 4 bits into 5-bit symbols Signup and view all the answers

What is the purpose of the control characters in the 4B5B line coding scheme?

Used for error detection and control characters Signup and view all the answers

What is the significance of the 5 symbol levels in the 4D-PAM5 line coding scheme?

Maps to -1V, -0.5V, 0, +0.5V, +1V Signup and view all the answers

How does the 8b/10b line coding scheme map groups of bits into symbols?

Maps groups of 8 bits into 10-bit symbols Signup and view all the answers

What is the main function of the Logical Link Control (LLC) sub-layer in the Data Link Layer?

Recognizes start/end of frames in the bitstream Signup and view all the answers

What does the notation DSAP=SSAP=0xAA signify in the context of Ethernet frame formats?

The 802.3 format with SNAP Signup and view all the answers

What is the purpose of the SNAP protocol in Ethernet frames?

To accommodate protocols that cannot be identified by the 1-byte SAP fields Signup and view all the answers

What are the two main components of the SNAP header in an Ethernet frame?

A 3-byte OUI and a 2-byte protocol type field Signup and view all the answers

What is the significance of the joint EtherType/Length definition in modern Ethernet frame formats?

It is used to identify the type of frame received Signup and view all the answers

What is the primary focus of the Data Link Layer (L2) in the OSI model?

Neighbour-to-neighbour communications Signup and view all the answers

What is the access method used in Ethernet, as discussed in the lecture?

CSMA/CD Signup and view all the answers