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24 Cards in this Set

  • Front
  • Back
What US agency governs data and voice communications? What state agency governs communications within its borders?
Federal Communications Commission (FCC)
Public Utilities Commission (PUC)
What do you call a private company that sells or leases communications services and facilities to the public?
Common Carrier
What do you call the local telephone services provided by a common carrier? The long distance services?
Local Exchange Carrier (LEC)
Interexchange Carrier (IXC)
What is the oldest and simplest MAN/WAN approach? What type of network does it use?
Circuit Switched Services
Public Switched Telephone Network (PSTN)
What are the two basic types of circuit switched services?
1. Plain Old Telephone Service (POTS)
2. Integrated Services Digital Network (ISDN)
What are the two types of narrowband ISDN services available?
1. Basic Rate Interface (BRI, basic access service or 2B+D)

2. Primary Rate Interface (PRI, primary access service or 23B+D)
Which circuit-switched service uses ATM to move data?
Broadband ISDN (B-ISDN)
What 3 B-ISDN services are currently offered?
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)
What are the 3 basic dedicated circuit architectures?
Ring, Star, and Mesh
List the T-Carrier Digital Hierarchy and corresponding data rates.
T-1 : 1.544 Mbps
T-2 : 6.312 Mbps
T-3 : 33.375 Mbps
T-4 : 274.176 Mbps
What is the ANSI standard for optical fiber transmission for speeds in the gigabit per second range?
Synchronous Optical Network (SONET)
List the lowest two SONET designations and corresponding data rates from the SONET digital hierarchy
OC-1 : 51.84 Mbps
OC-3 : 155.52 Mbps
What do packet switching users use to connect to the common carrier network?
Packet Assembly/ Disassembly Device (PAD)
What are the 2 methods of routing packets?
1. Datagram
2. Virtual Circuit
What are the 2 types of virtual circuits?
1. Permanent (PVCs)
2. Switched (SVCs)
What are the two data rates for a PVC?
1. Committed Information Rate (CIR)
2. Maximum Allowable Rate (MAR)
Packets sent at rates exceeding the CIR are marked...
Discard Eligible (DE)
What is the difference between CIR and MAR?
CIR is guaranteed while MAR sends data only when the extra capacity is available.
What are the 5 protocols used for packet switched services?
1. x.25
2. ATM
3. Frame Relay
4. Switched Multimegabit Data Services (SMDS)
5. Ethernet/IP packet networks
Which packet service is not standardized?
Switched Multi-megabit Data Services (SMDS)
<blank> uses PVCs that run over the Internet but appear to the user as private networks.
Virtual Private Networks
What are the two disadvantages of VPNs?
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
What 3 types of VPNs are currently in use?
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
How do you improve MAN/WAN performance?
1. Improve device performance
2. Improve circuit capacity
3. Reduce network demand