Cnt 4703 Test 3

Front 1

Broadcast Ethernet Address

Back 1

FF:FF:FF:FF:FF:FF
All bits are 1's - forty eight 1's.

Front 2

Multicast Ethernet Address

Back 2

Last Bit of First Byte of an ethernet address is 1.
(Odd Number)

Front 3

Unicast Ethernet Address

Back 3

Last Bit of First Byte of an ethernet address is 0.
(Even Number)

Front 4

1-Persistent CSMA/CD

Back 4

Collision Detection method: Continuously sense whether line is busy or not, transmit only when line becomes free.

Front 5

p-Persistent CSMA/CD

Back 5

Collision Detection method:
Set probability p, station will send frame with this probability.
With probability 1-p, station will wait a time slot and try to send again.
---If line is busy, act as though collision occured.
---If line is idle, go back to first step.

Front 6

non-Persistent CSMA/CD

Back 6

Collision Detection method:
If line is busy, wait randomly and try again. If line is idle, transmit.

Front 7

10BASE5

Back 7

"Thick Ethernet" or "Thicknet"
Thick Coax
500 m
Bus topology

Front 8

10BASE2

Back 8

"Thin Ethernet" or "Cheapernet"
Thin Coax
185 m
Bus Topology

Front 9

10BASE-T

Back 9

Twisted Pair - Uses four twisted pair cables
100 m
Star Topology

Front 10

10BASE-F

Back 10

10 Mbps
2000 m
Fiber Optic Cable
Star Topology

Front 11

LLC Layer

Back 11

Logical Link Control - Flow Control, Error Control, Part of Framing Duties.
Single Data Link Control for all IEEE LANs.

Front 12

MAC Layer

Back 12

Media Access Control - Defines specific access method for each LAN. Part of Framing Duties are handled here.
The MAC sublayer contains a number of modules for defining the access method and framing format for the corresponding LAN protocol.

Front 13

Repeater

Back 13

Operates only in the physical layer.
Receives signal and regenerates the original bit pattern. Resends the refreshed signal.

Front 14

Bridge

Back 14

Physical and Data Link Layers.
Acts as a repeater - regenerates any signal it receives.
Also has filtering capability: Checks destination address of frame and decides if it should be forwarded or dropped. Has a bridge table for forwarding that maps addresses to ports.

Front 15

Switch

Back 15

3-layer switch - type of router.
2-layer switch:
Physical and Data Link Layers
Switch is a bridge with many ports and faster performance. No competing traffic (collisions)

Front 16

Router

Back 16

Connects LANs and WANs. Has routing table. Routes packets based on logical addresses.

Front 17

Frame Relay

Back 17

Virtual Circuit WAN. 1.544 - 44.376 Mbps speeds
Just physical and Data Link Layers
9000 byte frame size
Virtual Circuits: Permanent & Switched

Front 18

ATM

Back 18

Asynchronous Transfer Mode
Cell Relay Protocol. Allows high speed interconnects of all networks.
The "highway" of the internet.

Front 19

Cell

Back 19

In Cell Networks, all data are loaded into identical cells that can be transmitted predictably and uniformly. Allows muxing to occur without problems caused by different size frames.

Front 20

ATM - How many standards?

Back 20

AAL1, AAL2, AAL 3 / 4, AAL5

Front 21

AP

Back 21

Access Point - Central Base station in a BSS (Optional)

Front 22

BSS

Back 22

Basic Service Set - Building Block of a wireless LAN. Made of stationary or mobile wireless stations and an optional central base station.

Front 23

ESS

Back 23

Extended service set - Two or More BSS's with AP's. Connected through a distribution system, which is usually a wired LAN.

Front 24

Ad-Hoc Architecture

Back 24

A BSS without an AP - A standalone network. Cannot send data to other BSS's.

Front 25

Infrastructure Network

Back 25

A BSS with an AP.

Front 26

FHSS

Back 26

Frequency Hopping Spread Spectrum - Uses 2.4 GHz ISM band, divided into 79 Subbands of 1MHz.
Pseudorandom number generator selects hopping sequence.
Modulation is 2 or 4-level FSK. Data rate is 1 or 2 Mbps.

Front 27

ATM - VPI

Back 27

Virtual Path Identifier - Identifies the specific Virtual Path.
VPI is the same for all virtual connections bundled in one VP. Used for addressing (routing)

Front 28

ATM - VCI

Back 28

Virtual Circuit Identifier - Identifies specific Virtual Circuit within the Virtual Path.
Used for addressing (routing)

Front 29

AAL1

Back 29

Supports constant bit rate information transfer, such as Video and Voice. Allows ATM to connect existing digital telephone networks. Segments the stream into 47 byte pieces and adds 1 byte of SAR header.

Front 30

AAL2

Back 30

Used for low bit rate traffic and short frame traffic such as Audio, video or fax. Mobile telephony uses AAL2.
Allows muxing of short frames into one cell.
Adds 3 bytes of header in addition to 1 byte SAR header.

Front 31

AAL3/4

Back 31

Supports connection oriented and connectionless data services. Adds 8 bytes of header/trailer in addition to 4 bytes of SAR header/trailer.

Front 32

AAL5

Back 32

Simple and Efficient Adaptation Layer (SEAL). Assumes all cells belonging to a single message travel sequentially and that control functions are included in upper layers of the sending application.

Front 33

AAL

Back 33

Application Adaptation Layer.
Enables two ATM Concepts:
ATM Must Accept any type of payload - data frames and streams of bits.
Payload must be segmented into 48-byte segments to by carried by a cell, then reassembled. AAL Defines the Segmentation and Reassembly sublayer.

Front 34

ATM Packet Composition - UNI

Back 34

User-to-Network Interface
[ GFC | VPI ]
[ VPI | VCI ]
[ VCI ]
[VCI |PT|CLP]
[ HEC ]
[Payload.....]

Front 35

ATM Packet Composition - NNI

Back 35

Network-to-Network Interface
[ VPI ]
[ VPI | VCI ]
[ VCI ]
[VCI |PT|CLP]
[ HEC ]
[Payload.....]

Front 36

SONET

Back 36

Synchronous Optical Network
Developed by ANSI (US)

Front 37

SDH

Back 37

Synchronous Digital Hierarchy
Developed by ITU-T (EU)

Front 38

SONET defines ____ Layers

Back 38

Four

Front 39

All STS frames have _____ rows.

Back 39

Nine

Front 40

STS-n Frames have ____ columns.

Back 40

n*90.
STS-1 = 90
STS-3 = 270

Front 41

A _______ is the optical link connecting two neighbor devices.
(SONET)

Back 41

section

Front 42

A ______ is the portion of the network between two multiplexers.

Back 42

Line

Front 43

A ______is the end-to-end portion of the network between two STS multiplexers.

Back 43

Path

Front 44

The ______ layer is responsible for the movement of a signal from its optical source to its optical destination.

Back 44

path

Front 45

The ____ layer is responsible for the movement of a signal across a physical line.

Back 45

line

Front 46

The ______ layer is responsible for the movement of a signal across a physical section.

Back 46

section

Front 47

An STS multiplexer is a ______ device.

Back 47

Four

Front 48

An add/drop multiplexer is a ______ device.

Back 48

Three Layer

Front 49

A regenerator is a ________ device.

Back 49

Two Layer

Front 50

VCIs in Frame Relay are called ______.

Back 50

DLCI's

Front 51

In Frame Relay, the EA field defines the number of bytes; it is _____ in the last byte of the address.

Back 51

1

Front 52

In ATM, ______ is for constant-bit-rate data.

Back 52

AAL1

Front 53

In ATM, _______is for short packets.

Back 53

AAL2

Front 54

In ATM, _____ is for conventional packet switching (virtual-circuit approach or datagram approach).

Back 54

AAL3/4

Front 55

In ATM, ______ is for packets requiring no sequencing and no error control mechanism.

Back 55

AAL5