WAN Flashcards
Dedicated Leased Line
▪ Logical connection that connects two sites through a service provider’s facility or telephone company’s central office
▪ More expensive than other WAN technologies because a customer doesn’t share bandwidth with other customers
Circut-Switched Conncetion
▪ Connection is brought up only when needed, like making a phone call
▪ On-demand bandwidth can provide cost savings for customers who only need periodic connectivity to a remote site
Packet-Switched Connection
▪ Always on like a dedicated leased line, but multiple customers share the bandwidth
▪SLAs used to guarantee a certain quality (5mbps at least 80% of the time) Virtual circuits are represented as dashed lines
RG-6
Coaxial cable
BPL
Broadband over Power Line
2.7 Mbps
HSPA+
Evolved High-Speed Packet Access
Wireless broadband
84 Mbps
Advancement over LTE and 4G
WiMax
Worldwide Interoperability for MIcrowave Access
Alternateive to DLS/Cell
Wireless fixed location service
DS0
Digital Signal 0
64 kbps channels
can be combined
T1
24 Channels
~1.5 Mbps
T3
672 Channels
~45 Mbps
E1
2.0 Mbps
Metro Ethernet
▪ Service providers are beginning to offer Ethernet interfaces to their customers
▪ Less expensive and more common than specialized serial ports used in a CSU/DSU
▪ Technology used by service provider is hidden from customer and they only need to connect their network’s router to a Smart Jack
PPP
Point-to-Point Protocol (PPP)
▪ Commonly used Layer 2 protocol on dedicated leased lines to simultaneously transmits multiple Layer 3 protocols (IP, IPX)
PAP
Password Authentication Protocol
PPP Authentication
▪ Performs one-way authentication between client and server
▪ Credentials sent in clear-text
CHAP
Challenge Handshake Authentication Protocol
CHAP
● Challenge-Handshake Authentication Protocol
● Performs one-way authentication using a three-way handshake
● Credentials are hashed before transmission
PPPoE
PPP over Ethernet (PPPoE)
▪ Commonly used with DSL modems
▪ PPPoE encapsulates PPP frames within Ethernet frames ▪ Allows for authentication over Ethernet
DSL
Digital Subscriber Line
ADSL
Asymmetric DSL (ADSL)
● Maximum distance to DSLAM: 18,000 feet
● Voice and Data on same line
● Downstream: Up to 8 Mbps
● Upstream: Up to 1.544 Mbps
SDSL
Symmetric DSL (SDSL)
● Maximum distance to DSLAM: 12,000 feet
● No simultaneous voice and data on same line
● Downstream: 1.168 Mbps
● Upstream: 1.168 Mbps
VDSL
Very High Bit-Rate DSL (VDSL)
● Maximum distance to DSLAM: 4,000 feet
● Downstream: Up to 52 Mbps
● Upstream: Up to 12 Mbps
HFC
Hybrid Fiber-Coax
Cable Modem
distribution network is a cable television infrastructure containing both coaxial and fiber-optic cabling
DOCSIS
Data-Over-Cable Service Interface Specifications
Cable Modem
POTS
Plain Old Telephone Service
Public switched telephone network (PSTN) consists of telephone carriers from around the world
PSTN
Public Switched Telephone Network
Public switched telephone network (PSTN) consists of telephone carriers from around the world
ISDN
Integrated Services Digital Network (ISDN)
▪ Supports multiple 64-kbps B (Bearer) channels
▪ Older technology designed to carry voice, video, or data over B channels
▪ D channel (data or delta channel) existed for 64-kbps signaling data
▪ Circuits classified as a basic rate interface (BRI) or primary rate interface (PRI):
● BRI: Offers a two 64-kbps B-channels with a 16kbps D-channel
● PRI: Offers a 1.472-Mbps data path over 23 B-channels and a 64kbps D-channel
Frame Relay
Losing market share due to cable and DSL
● Frame Relay sites connected to virtual circuits (VC)
● VCs are point-to-point or point-to-multipoint
● Low cost and widely available
● Always-on or on-demand
● Layer 2 technology Synchronous Optical Network (SONET)
SONET
Synchronous Optical Network (SONET)
▪ Layer 1 technology using fiber as media
▪ Transports Layer 2 encapsulation (like ATM)
▪ High data rates (155 Mbps to 10 Gbps)
▪ Covers large distances (20 km to 250 km)
▪ Physical topology can be a bus or ring
ATM
Asynchronous Transfer Mode FIBER AND SONET Rides on top of SONET Uses fixed-length CELLS as its PDU 53 Bite cell so makes it faster to move around
MPLS
Multiprotocol Label Switching
Used by service providers
Supports multiple protocols on same network
Can use both ATM and Frame Relay
DMVPN
Dynamic Multipoint Virtual Private Network
▪ Allow Internet to be used as WAN connection for secure site-to-site communication
▪ VPN tunnel has authentication and encryption so users on the unsecure network cannot read or decrypt the traffic without proper keys
▪ Can connect remote locations with low cost, instead of dedicated or leased-line access
OC
Optical Carrier
OC-1 ~51 Mbps
rest are multiples
OC-3~155 Mbps
How ATM and SONET measure data rates ATM and SONET
