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24 Cards in this Set
- Front
- Back
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What US agency governs data and voice communications? What state agency governs communications within its borders?
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Federal Communications Commission (FCC)
Public Utilities Commission (PUC) |
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What do you call a private company that sells or leases communications services and facilities to the public?
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Common Carrier
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What do you call the local telephone services provided by a common carrier? The long distance services?
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Local Exchange Carrier (LEC)
Interexchange Carrier (IXC) |
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What is the oldest and simplest MAN/WAN approach? What type of network does it use?
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Circuit Switched Services
Public Switched Telephone Network (PSTN) |
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What are the two basic types of circuit switched services?
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1. Plain Old Telephone Service (POTS)
2. Integrated Services Digital Network (ISDN) |
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What are the two types of narrowband ISDN services available?
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1. Basic Rate Interface (BRI, basic access service or 2B+D)
2. Primary Rate Interface (PRI, primary access service or 23B+D) |
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Which circuit-switched service uses ATM to move data?
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Broadband ISDN (B-ISDN)
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What 3 B-ISDN services are currently offered?
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1. Full duplex at 155.2 Mbps
2. Full duplex at 622.08 Mbps 3. Asymmetrical service (upstream of 155.2, downstream of 622.08) |
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What are the 3 basic dedicated circuit architectures?
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Ring, Star, and Mesh
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List the T-Carrier Digital Hierarchy and corresponding data rates.
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T-1 : 1.544 Mbps
T-2 : 6.312 Mbps T-3 : 33.375 Mbps T-4 : 274.176 Mbps |
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What is the ANSI standard for optical fiber transmission for speeds in the gigabit per second range?
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Synchronous Optical Network (SONET)
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List the lowest two SONET designations and corresponding data rates from the SONET digital hierarchy
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OC-1 : 51.84 Mbps
OC-3 : 155.52 Mbps |
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What do packet switching users use to connect to the common carrier network?
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Packet Assembly/ Disassembly Device (PAD)
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What are the 2 methods of routing packets?
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1. Datagram
2. Virtual Circuit |
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What are the 2 types of virtual circuits?
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1. Permanent (PVCs)
2. Switched (SVCs) |
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What are the two data rates for a PVC?
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1. Committed Information Rate (CIR)
2. Maximum Allowable Rate (MAR) |
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Packets sent at rates exceeding the CIR are marked...
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Discard Eligible (DE)
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What is the difference between CIR and MAR?
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CIR is guaranteed while MAR sends data only when the extra capacity is available.
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What are the 5 protocols used for packet switched services?
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1. x.25
2. ATM 3. Frame Relay 4. Switched Multimegabit Data Services (SMDS) 5. Ethernet/IP packet networks |
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Which packet service is not standardized?
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Switched Multi-megabit Data Services (SMDS)
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<blank> uses PVCs that run over the Internet but appear to the user as private networks.
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Virtual Private Networks
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What are the two disadvantages of VPNs?
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1. The unpredictability of internet traffic
2. The lack of standards for internet-based VPNs, so that not all vendor equipment and services are compatible |
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What 3 types of VPNs are currently in use?
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1. Intranet VPN - between organization offices over the internet
2. Extranet VPN - same as Intranet VPN, except that it connects several organizations together 3. Access VPN - enables employees to access organization's network from a remote location |
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How do you improve MAN/WAN performance?
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1. Improve device performance
2. Improve circuit capacity 3. Reduce network demand |
