Ccna Chapter 1

Front 1

MAC Address

Back 1

OSI Model Level 2
aka Hardware or Physical Address
48 bits long
1st 24 bits - Mfg ID #
2nd 24 bits - Unique Equip #

Front 2

Non-Routable IP Ranges

Back 2

OSI Layer 3
10.0.0.0
172.(16-31).0.0
192.168.0.0

Front 3

Class A IP Address Range

Back 3

0 - 126
ie. 125.0.0.0

subnet mask - 255.0.0.0

Front 4

Class B IP Address Range

Back 4

128 - 191
ie. 128.0.0.0

subnet mask 255.255.0.0

Front 5

Class C IP Address Range

Back 5

192 - 223
ie. 198.0.0.0

subnet mask - 255.255.255.0

Front 6

MAC Sublayer

Back 6

OSI Layer 2
Media Access Control is the lower sublayer in the Data Link Layer, it is responsible for hardware addressing, media access, and error detection of frames.

Front 7

LLC Sublayer

Back 7

OSI Layer 2
Logical Link Control is the higher of the Data Link sublayers responsible for error detection (not correction), flow control, and framing.

Front 8

UDP

Back 8

OSI Layer 4
User Datagram Protocol is a connectionless protocol in the TCP/IP stack that allows datagrams to be exchanged without acknowledgement.

Front 9

TCP

Back 9

OSI Layer 4
Transmission Control Protocol is a connection-oriented protocol that provides reliable delivery of data through the use of acknowledgments

Front 10

Causes of Network Congestion

Back 10

1. Too many hosts in BC domain
2. Broadcast storms
3. Multicasting
4. Low Bandwidth
5. Adding hubs in topology
6. A lot of ARP or IPX traffic

Front 11

OSI Model

Back 11

7. Application
6. Presentation
5. Session
4. Transport
3. Network
2. Data Link
1. Physical

Front 12

Physical Layer

Back 12

OSI Layer 1
Responsible for converting frames into electrical signals. Includes the transport media.
Deals with bits

Front 13

Data Link Layer

Back 13

OSI Layer 2
Ensures trustworthy transmission of data across a physical link, physical addressing, line discipline, network topology, error notification, ordered delivery of frames, and flow control.
Deals with frames

Front 14

Network Layer

Back 14

OSI Layer 3
Routing in implemented, establishing connections and path selection between two end systems.
Deals with packets

Front 15

Transport Layer

Back 15

OSI Layer 4
Responsible for reliable communication between end nodes over a network. Establishes, maintains and terminates virtual circuits, transport fault detection and recovery, and controlling the flow of information.
Deals with segments

Front 16

Session Layer

Back 16

OSI Layer 5
Responsible for creating, managing, and terminating sessions between applications and overseeing data exchange between presentation layer entities. Keeps different applications' data separate from other applications' data.

Front 17

Presentation Layer

Back 17

OSI Layer 6
Defines how data is formatted, presented, encoded, encrypted, and converted for use by software at the Applicaiton Layer.

Front 18

Application Layer

Back 18

OSI Layer 7
Supplies services to applications (such as email and file transfer) that are outside the OSI model. Determines the availability of resources necessary to make the intended connection.

Front 19

Data Encapsulation

Back 19

The process in which the in a protocol is wrapped in the data section of another protocol. In the OSI model each layer encapsulates the layer immediately above it as the data flows down the protocol stack.

Front 20

PDU

Back 20

Protocol Data Units - the resulting data from each layer in the OSI model (segments, packets, frames, bits)

Front 21

Access List

Back 21

A set of test conditions kept by routers that categorize packets. They help exercise control over network traffic.

Front 22

Data Packets

Back 22

OSI Layer 3
Use to transport user data through the internetwork.
Use routed protocols.

Front 23

Route Update Packets

Back 23

OSI Layer 3
Packets used to update neighbor routers about networks connected to the routers in the internetwork.
Use routing protocols.

Front 24

Router

Back 24

OSI Layer 3
Will not forward multicasts or broadcast. Will stop a broadcast storm. Use the logical (IP) address to determine the next router to send packet to. Provide connection for VLANs. Uses packet switching, packet filtering, path selection, and network to network communication.

Front 25

Hubs

Back 25

OSI Layer 1
Really just a multiport repeater. All devices connected are in the same broadcast and collision domain. Does not look at the traffic. Allow only one device per network segment to communicate at a time. Only operated in half duplex mode, so all connected devices must throttle back to half duplex.

Front 26

Bridges

Back 26

OSI Layer 2
A device for connecting two segments of a network together. A bridge filters, sends, and floods an incoming frame, based on the MAC address of that particular frame.

Front 27

Broadcast

Back 27

A data frame or packet that is transmitted to every node on the local network segment (broadcast domain).

Front 28

Switch

Back 28

OSI Layer 2
A device for connecting two segments of a network together. A bridge filters, sends, and floods an incoming frame, based on the MAC address of that particular frame.

Front 29

10Base2

Back 29

OSI Layer 1
RG-58A/U Thinnet Cable
185 meters or 607 feet

Front 30

10Base5

Back 30

OSI Layer 1
RG-8 Thicknet Cable
500 meters or 1,640 feet

Front 31

10BaseT

Back 31

OSI Layer 1
CAT 5,5e,6,6e,7 Twisted Pair
100 meters or 328 feet

Front 32

100BaseT, TX

Back 32

OSI Layer 1
CAT5e, 6, 6e, 7 Twisted Pair
100 meters or 328 feet

Front 33

100BaseFX

Back 33

OSI Layer 1
MMF, SMF Fiber
412 meters or 1,352 feet

Front 34

100BaseCX

Back 34

OSI Layer 1
TwinAx Cable
25 meters or 82 feet

Front 35

Full Duplex

Back 35

Uses two pairs of wire
No collisions because send and receive are on separate wires
100% efficient
Requires dedicated switch port

Front 36

Half Duplex

Back 36

Uses only one wire pair
30 - 40% efficient because collisions can occur
Only one host can transmit at a time.

Front 37

Broadcast Storm

Back 37

Could be cause by a bad NIC or a loop in the ethernet wiring topology. (two or more links exist between switches)
Broadcasts or multicasts are repeated over and over.

Front 38

Ethernet

Back 38

A connection media access method that allows all hosts on a network share bandwidth.
Simple to implement
Readily scalable
Troubleshooting is straight forward.
Uses CSMA/CD.

Front 39

CSMA/CD

Back 39

Carrier Sense Multiple Access / Collision Detection
When collision occurs:
1. Jam signal informs all devices
2. Invokes backoff algorithum.
3. Every device stops transmitting until timers expire.
4. Retransmissions start.

Front 40

Protocol

Back 40

A set of rules understood by a computer governing some process.

Front 41

Collisions

Back 41

When two computers on a network transmit at the same moment.
Cannot happen in full duplex mode, only in half duplex.

Front 42

Logical Topology

Back 42

It is the path a signal takes through a physical topology.

Front 43

Bit

Back 43

A binary digit (0 or 1)

Front 44

Byte

Back 44

8 bits or binary digits.
10110011 is a byte.

Front 45

Nibble

Back 45

4 bits or binary digits.
1011 is a nibble.

Front 46

Reference Model

Back 46

A conceptual blueprint of how some process should take place.
The OSI model is a conceptual model of how communications should take place.

Front 47

CISCO 3 Layer
Hierarchial Model

Back 47

1. Core Layer - network backbone.
2. Distribution Layer - Routers.
3. Access Layer - (aka desktop layer) - switches, network resources users need will be available locally.

Front 48

Network Segmentation

Back 48

Accomplished by:
Routers
Switches
Bridges
Breaks up collision domains, and in the case of routers, broadcast domains.

Front 49

Windowing

Back 49

Quantity of data segments the transmitting machine is allowed to send before receiving an acknowledgement from the receiving machine.

Front 50

Metric

Back 50

The distance to a remote network.
Different routing protocols use different methods to compute this distance, one example would be the number of routers it passes through (or a hop).

Front 51

Three Step Handshake

Back 51

Establishes a connection oriented communication with a remote device.
1. Connection agreement segment is requested for synchronization.
2. Acknowledge the request and establishes connection rules between hosts.
3. Acknowlege notifies destination host that connection agreement has been accepted and connection is established.

Front 52

Flow Control

Back 52

Receiver controls the sender.
Segments are delivered are acknowledged back to sender.
Segments without ack are resent.
Data flow is controled in order to avoid:
Congestion, Overloading, Data Loss

Front 53

Routing Protocols

Back 53

OSI Layer 3
Protocols that send route update packets
RIG, IGRP, EIGRP, OSPF

Front 54

Routed Protocols

Back 54

OSI Layer 3
Protocols used to support data traffic.
IPX, IPv4, IPv6

Front 55

VLAN

Back 55

Virtual LAN
A group of hosts with a common set of requirements as if they were attached to the broadcast domain regardless of their physical location.

Front 56

127.0.0.1

Back 56

Loopback IP Address
If you ping this address you can check if your NIC is working.