chapter 6 Flashcards
(106 cards)
1
Q
What are the key functions involved in Communication?
A
- Signal Distribution* Channel sharing* Data Routing* Message security* Metadata
2
Q
Signals are evolving towards digital as standards become established.
A
True
3
Q
All physical signal transmissions are _______ , while their modulation can convey _______ .
A
analogue , digital information
4
Q
What are the Types of Audio Networks?
A
- PSTN Voice Networks2. Intelligent Networks (IN)3. IP Multimedia Subsystems (IMS)4. Broadband5. WWAN (Wireless Wide Area Network)6. WLAN (Wireless Local Area Network)7. Audio Broadcast Networks
5
Q
What are the Two basic types of networks?
A
Audio Unicast Networks (PSTN)Audio Broadcast (Radio) Networks
6
Q
Public Switched Telephone Network [ PSTN ] was initially designed to support _______ ?
A
voice communication, not data or video.
7
Q
In PSTN, Despite progress, voice and data still often use separate networks.
A
True
8
Q
What was the Original core network design of PSTN?
A
circuit-switched, not packet-switched.
9
Q
Circuit Switching Utilizes a hierarchy with _____ levels.
A
5
10
Q
PSTNs are not very resilient.
A
False PSTNs were designed to be very resilient.
11
Q
Circuit switching allows higher _____ per call but at the expense of _______ .
A
Quality of Service (QoS)channel efficiency
12
Q
Later digital telecom networks evolved from the PSTN.
A
True
13
Q
What is the motivation behind IN Network Service Model?
A
- Introduced to address challenges of Early Digital Networks : - New features required long development times and were implemented directly within core switch systems.
14
Q
Early Digital Networks support _____ services while Intelligent Networks [ IN ] Support ______ services
A
specific , independent component-based
15
Q
IN enables the creation of flexible overlay networks, enhancing adaptability.
A
True
16
Q
In Recent years there’s a decline in the active development of new Intelligent Networks (IN) services.
A
True
17
Q
Emphasis is now on developing _____ and _____ rather than creating new telecom network protocols.
A
telecom services and APIs
18
Q
What are the Key Challenges of IP Multimedia Subsystems (IMS).
A
developing an application-layer control (signaling) protocol for: - voice/video sessions, - multimedia conferences, - messaging,
19
Q
How can Control can be achieved in IP Multimedia Subsystems (IMS)?
A
- using the SIP (Session Initiation Protocol) - that replaces the ITU’s earlier H.323 protocol.
20
Q
What are the three different types of MCU (Multipoint Control Unit) used by [ SIP ]
A
- full mesh- mixer- multicast
21
Q
Abbreviate : ADSLMCUSIPIMS
A
ASDL - Asynchronous Digital Subscriber LineMCU - Multipoint Control UnitSIP - Session Initiation ProtocolIMS - IP Multimedia Subsystems
22
Q
What type of physical networks does ADSL provide transmission capability over?
A
ADSL provides transmission capability over existing physical networks, such as copper-wire PSTN type access networks.
23
Q
In comparison to audio telephony, what bandwidth does ADSL typically use?
A
audio telephony - 3 kHz ADSL - 1 MHz
24
Q
High-frequency signals face more transmission challenges in ADSL.
A
True
25
What does WWAN stand for?
WWAN stands for Wireless Wide-Area Network.
26
What is the primary purpose of WWAN?
WWAN provides anywhere access for mobile or cell phone users.
27
In what ways do WWANs differ?
WWANs differ based on - geographic region and- generation (G) of the wireless network- such as 1G analogue and 2G digital.
28
How are WWANs designed in terms of user access?
WWANs are designed to share access to the wireless network among different users.
29
WWAN differ primarily on the way they _____ ?
are designed to share access to wireless network amongst different users.
30
WWAN networks can interoperate via _____ ?
gateways,
31
What limitation do WWAN transmitters or base stations have?
WWAN transmitters or base stations have a limited range.
32
abbriviate DAB
Digital Audio Broadcast
33
____ is the commonly used standard for digital radio.
DAB
34
What is the proposed enhancement to DAB and what features does it offer?
- DAB+ standard.- It features a better and more efficient transmission codec compared to the original DAB.
35
What innovations were the reason for the development of the early internet (1960's)
* Shift from batch to time-shared computers.* Shift from P2P topology* Shift from analogue to digital communication* Support for high capacity and resilient network* Large data was split into fixed size data packets* Shift from circuit switched to packet-switched data model
36
What is defined in a network communication protocol?
Answer:Data and control packets are defined in a network communication protocol.
37
What does each data packet carry?
Answer:Each data packet is labeled with the address.
38
What does multiplexing enable in a network?
Answer:Multiplexing enables packets from multiple messages to share the same part of the network.
39
Name the layers of the OSI model related to data packet protocols.
Answer:Application Layer, Transport Layer, Network Layer, Data Link Layer, Physical Layer.
40
Before communication, network elements need to be allocated network addresses.
T
41
How many addresses does IPv4 support?
Answer:IPv4 supports 32-bit addresses, approximately 4.3 billion.
42
How many bits do IPv6 addresses consist of?
Answer:IPv6 addresses consist of 128 bits.
43
What problem can arise when data is too large to be transmitted in one go?
Answer:When data is too large to be transmitted in one go, it may need to be split into smaller packets for efficient transmission.
44
At what level is routing typically performed, and is it transparent to applications?
Answer:Routing is typically performed at the network level, and it is usually transparent to applications.
45
What do routers examine to decide the path of data packets?
Answer:Routers examine the addresses of data packets to decide their path through the network.
46
How do routers communicate with each other in a network?
Answer:Routers communicate with each other using specialized routing protocols.
47
What are the Benefits for using wireless networks?
* Anywhere* Mobility* Less disruptive* Adaptivity
48
How do Ad Hoc Wireless Networks differ from Most global, wide area and local area wireless networks?
Answer:- Ad Hoc Wireless Networks have dynamic transmitters and routers- while Most global, wide area and local area wireless networks are infrastructure dependent and use fixed transmitters
49
List the types of Wireless data networks
Wireless LANs (WLANs) / WiFiWiMAXBluetoothZigBeeInfrared (IR)Ultra-Wideband (UWB)Satellite and Microwave
50
What does WiMAX stand for, and what is its purpose
Answer:WiMAX stands for Worldwide Interoperability for Microwave Access. It is a proposed wireless wide-area broadband access technology based on the IEEE 802.16 standard.
51
What is the range of Bluetooth for wireless communication?
Answer:Bluetooth has a range of about 1-100 meters for short-range wireless communication.
52
How does Bluetooth differ from Infrared (IR) in terms of line-of-sight requirements?
Answer:Unlike IR, Bluetooth does not require a line of sight between the transmitter and receiver.
53
What is ZigBee, and what communication protocols does it use?
Answer:ZigBee is a suite of communication protocols for Wireless Personal Area Networks (WPAN), based on the IEEE 802.15.4 standard.
54
_______ is a short-range, low-bandwidth data communication technology.
Infrared (IR)
55
______ Provide an efficient use of scarce radio bandwidth while enabling both high data rate wireless connectivity
Ultra-Wideband (UWB)
56
How do geostationary satellites provide global coverage in satellite communications?
Answer:Geostationary satellites use simpler antenna designs and configurations, and a small number of satellites can be interlinked to provide global coverage
57
What is the advantage of using WLANs at hot spots for mobile phones?
Answer:WLANs at hot spots offer faster and potentially cheaper mobile phone use.
58
What is required for seamless roaming between local area networks and wide area networks for mobile phones?
- a telecommunication system KA Generic Access Network (GAN), also known as UnlicensedMobile Access (UMA)
59
What are Femtocells, and what services do they provide?
Answer:Femtocells are small cellular access points providing enhanced coverage and converged voice, data, and video services such as IPTV.
60
How do Audio and Video (AV) broadcast Content Based Networks (CBN) differ from traditional Telecoms and Internet networks?
Answer:AV broadcast CBNs have different drivers compared to Telecoms and Internet networks, focusing on content-based communication.
61
What are the key characteristics of Telecoms networks, and how do they differ from the Internet initially?
Answer:Telecoms networks are developed for duplex or two-way, one-to-one communication, aiming for global interoperability. In contrast, the Internet initially evolved to support asynchronous communication.
62
What is the primary purpose of Digital AV CBN?[Audio and Video (AV) broadcast Content Based Networks (CBN)]
Answer:Digital AV CBN is designed to transmit streamed audio and video content.
63
AV CBN is oriented towards a _____ rather than a _____ customer base.
regional, global
64
______ is richer and more likely to be tailored to a specific region in terms of language and culture.
Video content
65
What limitation do receivers have in AV CBN regarding live broadcasts?
Answer:Receivers have limited control over live broadcasts in AV CBN.
66
video synchronization with audio and metadata complex in AV CBN
True
67
What aspect did the Internet primarily focus on in its early stages?
Answer:The Internet primarily focused on alphanumeric data [ letters and numbers ] transmission.
68
What is UDP, and what is its role in supporting multicast?
Answer:UDP stands for User Datagram Protocol and is used to support multicast.
69
How is the User Datagram Protocol (UDP) characterized in terms of transport?
Answer:UDP is an unreliable transport protocol, making it suitable for transmitting media streams.
70
When Streaming Media, what protocols are designed for streaming media over IP networks?
- RTP and RTCP - built on top of UDP- RTSP - built on top of TCP.
71
In residential & SME buildings _____ is used to access multiple services, e.g., voice, text, video,
single external comms line
72
How does ADSL compare to older technologies like ISDN and dial-up modems in terms of usage?
Answer:ADSL is replacing the use of older technologies like ISDN and dial-up modems.
73
What is Voice over IP (VolP)
The Use of IP network, to transmit voice as data packets
74
What are the three traditional types of networks for broadcasting audio-video entertainment content?
VHF TV, Satellite TV, and Cable TV.
75
How can analog television broadcast signals be enhanced with text data?
by embedding text data in the Vertical Blanking Interval (VBI) part of the television signal using a technology called Teletext.
76
What is DVB, and what does it replace?
DVB stands for Digital Video Broadcasting, and it replaces analog video broadcasting.
77
there are multiple standards for digital video broadcasting.
True
78
_____ is the most widely used system for digital video broadcasting?
DVB (Digital Video Broadcasting)
79
The DVB system is modeled like _______ at an abstract level.
TCP/IP
80
In what format is all data transmitted in the DVB system?
as MPEG-2 transport streams
81
What services are included in triple-play networks?
web documents, VoIP (Voice over Internet Protocol), and video streaming.
82
What is the additional feature in quad-play networks compared to triple-play networks?
Quad-play networks add mobile phone services to the offerings of triple-play networks.
83
IPv4 has more built-in support for multiplexing.
False.IPv6 new
84
What is Power Line Communication (PLC)?
PLC is an alternative method for accessing data and audio-visual content, utilizing the same network that conducts electricity to deliver energy.
85
How does PLC use electricity distribution wires for data transmission?
simultaneously distributes data by modulating electricity as a signal.
86
Wireless Personal Area Network (WPAN) typically covers a person or object within a _____ range.
10-meter
87
What are examples of Wireless Personal Area Network (WPAN)?
Bluetooth, Zigbee, and IR
88
_______ consists of wearable or implanted sensors monitoring vital body parameters and movements
Body Area Network (BAN)
89
How do electronic devices exchange digital information in Near-Field BANs?
by capacitively coupling picoamp currents through the body, using a low-frequency carrier (less than one megahertz).
90
______ demonstrated that a Near-Field BAN system can support various business processes
Zimmerman
91
wireless access devices can be static
True - e.g : Internet cafes
92
What is the difference between mobile and wireless services?
Mobile services involve access on the move, while wireless services refer to radio frequency access.- mobile devices like phones and GPS Vs.- Large screen Tvs ...
93
Why is determining the network location or address important for mobile users?
In order to receive data. It is easier to send data when the user can locate the nearest access network base station.
94
The main functions of Mobile IP in single-path routing include _____, ______ and ______ .
Discovery, Registration, and Tunnelling.
95
What are the 2 dimensions used to classify routing in mobile users?
- fixed vs. variable routes - single vs. multi-path routes.
96
How do ad hoc networks differ from fixed computer networks?
Ad hoc networks use connections established for the duration of a session and do not require a base station or fixed router, unlike fixed computer networks.
97
What is the significance of the term "ad hoc" in Mobile Ad hoc Networks (MANETs)?
In MANETs, the term "ad hoc" indicates that each node is willing to forward data for other nodes
98
How do devices in MANETs form networks without dedicated router nodes?
- They discover others within range to form a network
99
How are connections established in multi-hop ad hoc networks?
Connections in multi-hop ad hoc networks are made over multiple nodes,
100
MANETs are particularly useful in situations where there is ________
no existing network infrastructure
101
Why are ICT resources connected to the Internet often protected, and how is access controlled?
ICT resources are protected to control access by specific users or closed user groups. Access is controlled using measures such as firewalls, NATs, and VPNs.
102
What are the two levels at which firewalls can be designed, and how do they operate?
Firewalls can be designed at packet-level or application level. - Packet-level firewalls operate by examining individual packets- Application-level firewalls operate at the application layer.
103
How are VPNs useful?
VPNs are useful to restrict resource access on remote networks to specific users over the public Internet
104
What is multicast communication, and why is it useful?
Multicast communication involves sending the same message from a single source to a defined group of multiple receivers. It is useful for efficiently transmitting data to multiple recipients simultaneously.
105
How can large multicast groups be managed more efficiently?
Large multicast groups can be managed more efficiently by splitting them into hierarchies.
106
Why is there a need for low-cost networks and access terminals in certain regions?
the population may not be able to afford high-cost networks.
