attachmentsSlide 1 of 2

  • attachment_1attachment_1
  • attachment_2attachment_2

UNFORMATTED ATTACHMENT PREVIEW

QUESTION 1 1. The Kingsbury Agreement essentially re-affirmed the idea that AT&T could continue to operate as a regulated monopoly free from competition. True False 10 points QUESTION 2 1. Which of the following expanded the digital communications industry to new entrants, thus beginning the dot.com era? a. b. c. d. The Kingsbury Agreement Telecommunications Act of 1996 The Modified Final Judgment (MFJ) Hush-a-Phone decision 10 points QUESTION 3 1. The Cable Communications Policy Act of 1984 addressed a new national policy intended to encourage greater competition within the CATV industry. True False 10 points QUESTION 4 1. Which act or judgment enabled non-AT&T devices to be attached electrically to the AT&T telephone network? a. 1913 Kingsbury Agreement b. Communications Act of 1934 c. 1956 Hush-a-Phone decision d. Caterfone decision 10 points QUESTION 5 1. Which regulatory act created seven Regional Bell Operating Companies (RBOCs) from 22 former Bell Operating Companies (BOCs)? a. 1913 Kingsbury Agreement b. 1956 Hush-a-Phone decision c. 1982 Modified Final Judgement (MFJ) d. Telecommunications Act of 1996 10 points QUESTION 6 1. The common channel signaling (CCS) system provides a separate network dedicated to control and signaling over the PSTN. This enables subscribers to establish calls on an on-demand basis. True False 10 points QUESTION 7 1. Select the correct statement(s) regarding in-band and out-of-band signaling. a. with out-of-band signaling, control signals take place on the same physical circuits as the actual data traffic b. both in-band and out-of-band signaling takes place over the normal data traffic network c. both in-band and out-of-band signaling takes place over a dedicated control and signal network d. with in-band signaling, control signals take place on the same physical circuits as the actual data traffic 10 points QUESTION 8 1. What is the difference between interLATA and intraLATA calls? a. b. c. d. a LATA controls all interLATA calls interLATA calls must be switched through an IXC facility only intraLATA calls go through an IGF interLATA calls go through the Internet 10 points QUESTION 9 1. An International Gateway Facility (IGF) is a facility responsible for the switching of all calls regardless of whether the calls are local, national, or international. True False 10 points QUESTION 10 1. What is the importance of NPA? a. It provides a hierarchical telephone numbering scheme that enables call connection at the regional and global levels b. It provides specifications for international IPv4 addressing c. It is an ITU policy that enhances global competition for telephone services d. It was the first standards organization which led to the creation of ANSI and OSI 10 points QUESTION 11 1. What is CPE? a. communication devices that reside at the subscriber location but are the responsibility of the service provider b. communications processing equipment that reside at the service provider’s central office c. subscriber communication devices that connect to the service provider network, but are owned, operated, and maintained by the subscriber d. a switching device that provides CENTREX services 10 points QUESTION 12 1. A PBX switch is considered part of the PSTN and not part of the CPE. True False 10 points QUESTION 13 1. Select the correct statement(s) regarding a DS0. a. DSO is a digitized analog signal (i.e., typically supporting a 4kHz bandwidth voice signal) b. DSOs are created using PCM techniques that adhere to Nyquist Sampling rates c. DS0s use a bit-depth of 8 bits per sample d. all are correct statements 10 points QUESTION 14 1. A DS0 is a basic 64kbps building block for channelized T-Carrier and SONET standards. True False 10 points QUESTION 15 1. What do T-Carriers, SONET and SDH have in common? a. b. c. d. supports 64 DS0s per frame transmission rates operate at 8000 frames per second all standards depend upon fiber optic physical layer medium all are common 10 points QUESTION 16 1. How is the Channelized T-1 rate of 1.544 Mbps determined? a. 64 frames/second * ((24 DS0s/frame * 8 bits/DS0) * 1 FB) b. 8000 frames/second * ((24 bits/frame) + 1 FB) c. 8000 frames/second * ((24 DS0s/frame * 8 bits/DS0) + 1 FB) d. 64 frames/second * ((193 bits/frame * 8 bits/DS0) + 1 FB) 10 points QUESTION 17 1. Select the correct statement(s) regarding Wide Area Networks (WANs). a. b. c. d. WANs operate at the OSI Layer 3 (network layer) today’s WANs only use IPv4 and IPv6 at the OSI network layer WANs operate at the OSI Layer 2 (data link layer) a WAN is a wireless area network, implemented by cellular service providers 10 points QUESTION 18 1. Select the correct statement(s) regarding Frame Relay (FR). a. FR is a connectionless standard that operates at the OSI layer 2 b. FR packets are fixed length, therefore transmission delays are predictable c. FR is a connection oriented variable sized frame standard that operates at the data link layer d. all of the statements are correct 10 points QUESTION 19 1. Select the correct statements regarding Asynchronous Transfer Mode (ATM): a. ATM is a variable-length cell standard that supports voice, video and data b. ATM is connection-oriented c. ATM is a connectionless network layer protocol similar to IP, in which fixed cell sizes enable predicable latency and quality-of-service (QoS) d. a and b are correct statements 10 points QUESTION 20 1. ATM over SONET provides high data rate capacities, predictable delays and quality-ofservice; however, both ATM and SONET are complex technologies to implement. True False 10 points QUESTION 21 1. Select the correct statement(s) regarding SONET and SDH. a. STS describes the SONET electrical signal, while STM describes the SDH electrical signal b. OC describes the optical signal on both SONET and SDH c. An STS-3 equals an STM-1, which is 155.52 Mbps d. All of the above are correct 10 points QUESTION 22 1. What is a true statement regarding WDM? a. WDM is another name for SONET. b. SONET can be implemented onto one of the wavelengths in a WDM or DWDM multiplexer. c. Since WDM and SONET are competing optical signal standards, they cannot be used together on the same fiber optic cable. d. There are no true statements above. 10 points QUESTION 23 1. Wavelength Division Multiplexing (WDM) is used to combine several optical channels (i.e., wavelengths) into an aggregate broadband signal that is transmitted over a fiber optic cable. True False 10 points QUESTION 24 1. Select the correct statement(s) regarding Carrier Ethernet (CE). a. the Metro Ethernet Forum (MEF) created a CE framework to ensure the interoperability of service provider CE offerings b. MEF certifies CE network providers, manufacturers and network professionals to ensure interoperability and service competencies c. MEF certified services include E-Line, E-LAN, E-Tree, E-Access, and E-Transit d. all are correct statements 10 points QUESTION 25 1. Select the correct statement(s) regarding the PBX. a. Organizations using PBXs must have technical expertise on their staffs to operate and maintain them b. A PBX can support both analog and digital communications c. Numerous PBXs can be configured as a distributed network to support organizational requirements d. All are correct 10 points QUESTION 26 1. Select the correct statement(s) regarding CENTREX. a. CENTREX systems reside at the service providers central office, however, the operations and maintenance are still the responsibility of the user organization b. CENTREX systems reside at the service providers central office, and the operations and maintenance responsibilities belong to the service provider c. CENTREX systems offer greater choice to users because the service provider has better and more sophisticated equipment than single organizations have d. All are correct 10 points QUESTION 27 1. ACDs are considered switching PBXs that employ IVRs and are typically used in call centers. ACDs can be networked across the PSTN. True False Chapter 6 Local and Personal Area Networks 1 6.1 Introduction Local area networks (LANs) are comprised of multiple PCs and servers interconnected to one another through guided mediums. (e.g., 802.3 Ethernet)   Networks serving a single organization or location Wireless LAN (WLAN), allows PCs to connect wirelessly to wired network through access points (APs). (e.g., 802.11 Wi-Fi) Wireless Personal Area Networks (WPANs) are smaller wireless networks (e.g., 802.15 Bluetooth and ZigBee)   2 6.2 Local Area Network Architecture Physical and logical networks are arranged in mesh, star, bus, and ring, and hierarchical tree architectures.     The physical topology describes how network devices are physically connected. The logical topology describes how connected devices communicate with one another over the physical topology. The LAN’s physical and logical topologies may differ from one another  3 Ex., network devices may be connected in a star topology through a hub device, but logically communicate to one another as a shared bus topology 6.2 Local Area Network Architecture 4 6.2 Local Area Network Architecture LANs are built on peer-to-peer (P2P) or client-server concepts.   P2P network – computers connect directly to one another to share information.     Client-server – servers provide centralized services and data storage for clients.  5 No central storage of shared files or applications – multiple copies can exist Simple form of network – easily implemented No centralized access or authentication Servers provide access to peripheral devices, other networks, applications and databases, email, storage, and security functions etc. 6.2.1 Centralized and Decentralized Access Control Medium Access Control (MAC) – defines the process by which devices on the network can access the shared medium   Network Interface Unit (NIU) or Network Interface Card (NIC) MAC layer procedures can involve centralized or distributed control model.   OSI RM Data Link Physical 802.3   LLC MAC Physical Logical Link Layer (LLC) – handles communication between upper layers and lower layers  Media Access Control (MAC)     6 Adds control info Implemented in software (driver sw for Network Interface Card, NIC) Preamble generation (if used) Data encapsulation – framing, addressing, error detection Implemented in network interface card (NIC) hardware Provides medium access 6.2.1 Centralized and Decentralized Access Control Centralized access control – Centralized controller determines when the stations can access the shared medium (polling, tokens) – ex.,Token Ring     Passing of control packets requires additional overhead Failure of the central controller disrupts the entire network Deterministic access – node that is granted access has a guarantee that it can transmit data without collisions Decentralized (Distributed) access control – Each station assumes responsibility for controlling its access to the shared network – ex., Ethernet   7 Non-deterministic access control (aka contentious MAC) – no guarantees 6.2.1 Centralized and Decentralized Access Control  With decentralized/distributed access control data collisions on the shared medium can occur.  Two examples: IEEE 802.3 shared Ethernet requires CSMA/CD, IEEE 802.11 CSMA/CA    Carrier sense—Each station continuously listens for traffic Multiple access—Numerous stations share baseband medium Collision Detect—If two or more stations transmit at the same time then data frames will collide   8 Jamming Signal – Any node detecting data collision sends jamming signal causing other nodes to cease activities for a random period of time Collision Avoidance – stations are proactive in attempting to prevent collisions 6.2.2 DTE and DCE The data terminal equipment (DTE) and data communications equipment (DCE) helps identify interface characteristics between devices in a network.    DTEs are typically end devices such as terminals, computers, and servers DCEs typically describe network equipment such as modems It is helpful to think of DTEs and DCEs as types of interfaces vice whole devices, especially considering that many of today’s devices have both DTE and DCE interface ports.  9 6.2.2 DTE and DCE  Digital FDX – dedicated send and receive paths – typically used with modems (9, 15, 25, 36 pin connectors)         RS-232 (EIA 232),TIA-232-F (2012), (DB-25 pin connector) RS-422, RS-423, RS-485 EIA-530, EIA/TIA-561 & 562 TIA-574 (9 pin) ITU V.24,V.35 ITU X.21, X.25 Many more… Used with computers and digital networks (e.g.,T-1, CSU/DSU (channel service unit/data service unit), routers,WAN interface, fiber optic cables, Ethernet, etc.) 10 6.2.2 DTE and DCE Twisted Pairs to minimize Crosstalk RJ-45 RJ-45 1 2 TX+ TX- TX+ TX- 3 4 RX+ TRD2+ RX+ TRD2+ 5 6 TRD2RX- TRD2RX- 7 8 TRD3+ TRD3- TRD3+ TRD3- Note: pins 4, 5, 7, 8 are not used for slower 100BaseT Ethernet (i.e., only two pairs required). 1000BaseT requires four pairs. 11 6.2.2 DTE and DCE What happens when both the network (ex. network switch) and computer attempt to transmits on the same wired pair? Twisted Pairs to minimize Crosstalk RJ-45 RJ-45 1 2 TX+ TX- TX+ TX- 3 4 RX+ TRD2+ RX+ TRD2+ 5 6 TRD2RX- TRD2RX- 7 8 TRD3+ TRD3- TRD3+ TRD3- Note: pins 4, 5, 7, 8 are not used for slower 100BaseT Ethernet (i.e., only two pairs required). 1000BaseT requires four pairs. 12 Network Switch 6.2.2 DTE and DCE  Need a way to distinguish flow of data between the terminal-side and network-side devices. Describes interface and direction of data flow.   13 Data Terminal Equipment (DTE) – ex., computers, servers, etc. Data Communications Equipment (DCE) – ex., switches, etc. 6.2.2 DTE and DCE Twisted Pairs to minimize Crosstalk DTE DCE 1 2 TX+ TX- TX+ TX- 3 4 RX+ TRD2+ RX+ TRD2+ 5 6 TRD2RX- TRD2RX- 7 8 TRD3+ TRD3- TRD3+ TRD3- Network Switch Note: pins 4, 5, 7, 8 are not used for slower 100BaseT Ethernet (i.e., only two pairs required). 1000BaseT requires four pairs. A DTE will transmit data on TX+ & TX-, while the DCE will listen, or receive data on TX+ & TX-. A DCE will transmit data on RX+ & RX-, while the DTE will listen or receive data on RX+ & RX14 6.2.2 DTE and DCE Cross-Over Cable DTE DTE 1 2 TX+ TX- TX+ TX- 3 4 RX+ TRD2+ RX+ TRD2+ 5 6 TRD2RX- TRD2RX- 7 8 TRD3+ TRD3- TRD3+ TRD3- Note: pins 4, 5, 7, 8 are not used for slower 100BaseT Ethernet (i.e., only two pairs required). 1000BaseT requires four pairs. 15 6.3 IEEE 802.3 Ethernet LAN   Shared Ethernet – all connected devices receive all transmitted data frames regardless of whether they are the intended recipient or not. Switched Ethernet – devices are connected to a switch. Each connection is a dedicated link, therefore no data collisions occur and the need for an algorithm such as CSMA/CD is not required. 16 A HUB 2 WIRE, 1 PAIR HDX CSMA/CD B HUB C 17 D HUB 4 WIRE, 2 PAIR FDX CSMA/CD A TX B RX RX TX HUB RX TX RX TX C 18 D SWITCH 4 WIRE, 2 PAIR FDX NO COLLISIONS A TX B RX RX TX RX TX RX TX C 19 D 6.3.2 Ethernet 802.3 Selected Standards  Ethernet 802.3 describes a family of specifications at Layers 1 & 2 of the OSI RM       E.g., 100BaseT, 1GBaseT, 10Base2, 100BaseFX, 10Broad36 (obsolete) Decentralized (distributed), Non-determinant access Shared & HDX Switched Ethernet – CSMA/CD Switched FDX Ethernet – no collisions Physical Medium – UTP, Coax., Fiber Optic Data Link Layer – two sublayers  Medium Access Layer (MAC)   20 48 bit MAC address (NIC) fixed to hardware and manufacturer Logical Link Layer (LLC) 6.3.2.2 100Base-T  100Base-TX, Fast Ethernet    Cat 5e, 100Mbps theoretical Configured with hub or switch in center Half-Duplex over two wire (Cat 5e)   21 1 TX+ 2 TX- 3 RX+ 6 RX- 100BaseFX over MMF or SMF optic cables 4B5B binary block line coding at 125 Mbaud   Signal Full-Duplex over four wire (Cat 5e) through an Ethernet switch   CSMA/CD MAC mechanism PIN 8B/10B is also common NRZI (“I for inverted) Line Coding (+v = “0”, -v = “1”) 6.3.2.3 1000Base-T (GbE)  1000Base-T     1Gbps (GbE), Baseband uses all 8 Cat5e wires (four pairs) Full-Duplex, 125 Mbaud, over all four pairs (magnetic hybrids) PAM-5 coded signaling (M=5 levels/symbol at -2, -1, 0, +1, +2)    22 N=2 bits data, one level for FEC (Forward Error Correction) C(bps) per pair =125Mbaud * 2 = 250 Mbps over each pair C(bps) total = 250Mbps * 4 = 1Gbps tx rx C(bps) =125Mbaud * 2 =250 Mbps Hybrid C(bps) =125Mbaud * 2 =250 Mbps Hybrid rx Hybrid tx Hybrid 6.3.2.3 1000Base-T (GbE) tx rx tx rx 1000Base-T 1Gbps (GbE), CAT5e 125 Mbaud Full-Duplex, four pairs rx 23 C(bps) =125Mbaud * 2 =250 Mbps Hybrid tx C(bps) =125Mbaud * 2 =250 Mbps tx Hybrid rx Hybrid tx Hybrid PAM-5 (M=5) tx rx rx N=2 bits 6.3.2.4 10GBase-T  10GBase-T (2006)     10Gbps, Baseband over four pairs Full-Duplex – switched Ethernet Cat 6 (600MBaud), Cat 7 (750MBaud) UTP RJ45, 8 pin modular connectors PAM-16 coded signaling (M=16 levels per symbol) N(bits) = log2M = log216 = 4 bits C (bps) = 750E6 baud * 4 = 3 Gbps 4 * 3 Gbps = 12 Gbps tx rx C(bps) =750E6 baud * 4 = 3Gbps Hybrid C(bps) =750E6 baud * 4 = 3Gbps Hybrid rx Hybrid tx Hybrid 6.3.2.4 10GBase-T tx rx tx rx 10GBase-T 10Gbps (GbE), Cat 6, Cat 7 600 MBaud to 750 MBaud PAM-16 rx 25 C(bps) =750E6 baud * 4 = 3Gbps Hybrid tx C(bps) =750E6 baud * 4 = 3Gbps tx Hybrid rx Hybrid tx Hybrid M=16, N=4 bits tx rx rx 6.3.2.5 Ethernet and Fiber Optics    Single mode fiber (SMF) and multimode fiber (MMF) optic cables are popular due to decreasing costs of optical transceivers and fiber cables. The 802.3 standard includes several versions using either SMF or MMF. Example: -100BASE-FX: “FX” indicates fiber optic cable, baseband signaling in either half-duplex (HDX) or fullduplex (FDX) modes.     26 Transceivers perform optical-electrical-optical (OEO) conversions Star configuration SMF cables extends this distance to 10 km. 4B5B encoding and NRZI line coding methods 6.4 IEEE 802.11 Wireless LAN     IEEE 802.11 wireless local area network (WLAN) consists of a family of WLAN specifications that have technically evolved over time. ISM (Industrial, Scientific, and Medical) – frequencies in the 2.4GHz (2.4 GHz to 2.5GHz) and 5GHz (5.725 GHz to 5.875 GHz) bands – no licensing. Interference issues with other devices (e.g., home security cameras, baby monitors, cordless phones, garage door openers, nearby microwave ovens, other WLAN networks, etc. ) Technical innovations introduced to decrease interference issues. 27 6.4.1 IEEE 802.11 Physical Architecture   Shared wireless channels contend with radio frequency interference (RFI). To limit the impact:  28 direct sequence spread spectrum (DSSS) and orthogonal frequency division multiplexing (OFDM) techniques were adopted.  Both spread the signal across a wider frequency band, thus reducing the impact of any narrow band RFI.  OFDM is not considered a spread spectrum technique 6.4.1 IEEE 802.11 Physical Architecture  802.11 WLANs     operate half-duplex over unlicensed ISM band Centralized or distributed/decentralized access process. Peer-to-peer (P2P) mode (aka ad hoc) – no centralized processes or servers Access Point (AP) – client/server network that operates as a centralized or decentralized wireless network  29 nodes can connect to one another, as well as to a wired network that provides services (e.g…

Do you similar assignment and would want someone to complete it for you? Click on the ORDER NOW option to get instant services at essayloop.com

Do you have a similar assignment and would want someone to complete it for you? Click on the ORDER NOW option to get instant services at essayloop.com. We assure you of a well written and plagiarism free papers delivered within your specified deadline.