Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Computer Networking > ICND1 > Flashcards

ICND1 Flashcards

1
Q

OSI Layers

A

Physical, Data Link, Network, Transport, Session, Presentation, Application

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the data link layer address for Ethernet

A

MAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the non-overlapping channels in the 2.4 Ghz frequency for wireless access points.

A

1, 6, and 11

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Basic function of IPS

A

Learn normal behavior of network and block or warn when an abnormality is observed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

IOS Configuration, interface mode, ‘ntp broadcast’

A

Sends NTP broadcasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do the following port light colors indicate on a Cisco switch?

no light
green
blinking green
alternating green-amber
amber
blinking amber
A

no light - no link, or port is admin down.

green - link present

blinking green - activity (normal operation)

alternating - link fault: errors such as excessive collisions, CRC, alignment, and jabber.

amber - port blocked by STP while listening or learning

blinking amber - port is in STP blocking state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What conditions might cause a switch port status light to remain unlit?

A

admin down or link down.

Link down may be due to encapsulation or other layer 2 protocol mismatch, a bad or incorrect cable, or a lack of signal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

For numbered ACLs what are the number ranges for standard and extended IP ACLs

A

standard: 1-99 and 1300-1999
extended: 100-199 and 2000-2699

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the OSI Application Layer

A

This layer interacts directly with applications.

These services include FTP, SMTP, HTTP, DHCP, et al.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the OSI Presentation Layer

A

This is not always used. It handles translation, compression, and encryption. Translation changes the data to be understood by different types of computers such as changing LF to CRLF in an ASCII FTP transfer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the OSI Session Layer

A

Creates, manages, and terminates sessions between communicating nodes. These are APIs such as NetBIOS, TCP/IP Sockets aka Python SocketIO, and RPC.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the OSI Transport layer

A

It has two main parts. One is keeping track of what data comes from what application and combining that data into a single flow for use by the lower layers. The receiving device reverses this operation. Dividing the data into segments ready for layer 2 and 3 encapsulation is also done here.

Part 2 TCP/UDP - providing either connection-oriented (TCP) or connectionless (UDP) services. Connection-oriented services include flow control, keeping packets in order, recovering from lost transmissions or errors. Connectionless services do almost nothing apart from keeping track of which application the traffic belongs to. They are called best-effort because if the data is lost there is no attempt to recover it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the OSI Network Layer

A

This layer handles logical addressing, routing, datagram encapsulation, fragmentation and reassembly, and error handling and diagnostics. Error handling and diagnostics doesn’t include data recovery. The most common example of this is a routing protocol using a ‘hello’ protocol to verify the link is up.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the OSI Data Link Layer

A

This includes logical link control, media access control, data framing, local addressing, and error detection and handling. Common error detection includes the checksum on Ethernet frames.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the OSI Physical Layer

A

This includes hardware specifications, encoding and signaling, and data transmission and reception.
Layer 1 devices are CSU/DSU, transceivers, and repeaters that take bit streams and convert or repeat them without regard to the structure at the other layers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 7 layers of the OSI model

A

Physical, Data Link, Network, Transport, Session, Presentation, and Application

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the major letters used in the ‘show ip route’ command and their associated protocol

A 
C - connected
S - static
R - RIP
B -BGP
D - EIGRP
EX - EIGRP external
I - IGRP (deprecated)
O - OSPF
i - IS-IS
o - ODR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which protocol is used by Ethernet to control transmission over a shared medium. Which similar protocol is used by WiFi?

A

CSMA/CD for Ethernet
(Carrier Sense Multiple Access / Collision Detection)

CSMA/CA for WiFi (Carrier Sense Multiple Access / Collision Avoidance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q 
Answer one to \_\_\_\_ for the following:
Unicast
Multicast
Broadcast
Anycast
A

Unicast: One to One
Multicast: One to Many
Broadcast: One to All
Anycast: One to Any

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which method do network devices use to translate a name to an IP address

A

DNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the RFC number for private IPv4 address space?

A

RFC 1918

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

List the RFC 1918 address ranges

A
  1. 0.0.0 - 10.255.255.255
  2. 16.0.0 - 172.31.255.255
  3. 168.0.0 - 192.168.255.255
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

List differences between UDP and TCP

A

TCP deliveries all packets in order

UDP delivers whatever packets arrive.

TCP has higher overhead.

UDP is better for real-time applications like VoIP

TCP is connection-oriented

UDP is connectionless

TCP is slower

TCP does error checknig and error recovery

UDP does error checking but discards and does not recover

TCP has a handshake UDP does not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is TCP sliding window?

A

The adjustment in quantity of data sent before the sender receives an acknowledgement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are the 3 steps in a TCP 3-way handshake.
SYN (initiator) SYN-ACK (responder) ACK (initiator)
26
List the differences between the TCP/IP reference model and the OSI reference model. (Layer names will be covered on other slides)
OSI is protocol independent OSI is a reference model and TCP/IP is an implementation OSI model has 7 layers and the TCP/IP model has 4 layers.
27
What OSI layer(s) provider similar functionality to the TCP/IP Application layer?
Application, Presentation, and Session
28
What TCP/IP model layer provides the functionality of the OSI Presentation layer?
Application
29
What TCP/IP model layer provides the functionality of the OSI Session layer?
Application
30
What TCP/IP model layer provides the functionality of the OSI Transport layer?
Transport
31
What TCP/IP model layer provides the functionality described by the OSI Network layer.
Internet layer
32
What TCP/IP model layer provides the functionality described by the OSI data-link layer?
Network Access layer
33
What TCP/IP model layer provides the functionality described by the OSI physical layer?
Network Access layer
34
What OSI layer(s) describe the functionality of the TCP/IP Transport layer?
Transport layer
35
What OSI layer(s) describe the functionality of the TCP/IP Internet layer.
Network layer
36
What OSI layer(s) describe the functionality of the TCP/IP Network Access layer
Data Link layer and Physical layer
37
List the main IOS Command modes
``` User EXEC Privileged EXEC Global configuration Interface configuration Subinterface configuration ROM monitor ```
38
List configuration required for SSH access
``` line vty 0 4 login local transport input ssh/all username xxx secret xxx hostname router ip domain-name example.com crypto key generate rsa ```
39
Command to view table of interface mac address mapping
show mac address-table
40
Command to view directly connected Cisco devices
show cdp neighbors
41
Commands to enable lldp globally, disable it on an interface, and view discovered neighbors.
global: lldp run interface: no lldp transmit EXEC: show lldp neighbors
42
What is LLDP an acronym for?
Link Layer Discovery Protocol
43
Describe the three possible response types for switchport port-security
protect: block traffic from any MAC addresses beyond the number allowed restrict: same as protect but will log violations shutdown: will err-disable the port if the number of allowed MAC addresses are exceeded
44
Command for a sticky mac in port security
switchport port-security mac-address sticky
45
Command to limit number of mac addresses on port
switchport port-security maximum n
46
Command to enable port security
switchport port-security
47
Command to configure port security response type
switchport port-security violation [protect, restrict, shutdown]
48
Command to set port as static access
switchport mode access
49
Command to set port to attempt to negotiate trunk with DTP capable switch
switchport mode dynamic desirable
50
Default switchport DTP mode
dynamic auto
51
List some conditions which will cause a switch to have its VLAN database replaced by a neighboring switch
If VTP domain is null and packet is received from switch with non-null domain. If the password is set on the non-null switch then the null switch won't inherit the VTP setup.
52
A switch running in VTP client mode version 2 on cbtnuggets.com domain is not receiving the revision updates from the VTP server on version 2 from domain CBTNuggets.com. What is the problem?
Domain names don't match - case sensitive.
53
Command for routing protocol details
show ip protocols
54
Command too apply ACL to vty
access-class n [in|out]
55
Configure DHCP server range 192.168.1.20-100.
ip dhcp excluded-address 192.168.1.1 192.168.1.19 ip dhcp excluded-address 192.168.1.101 192.168.1.254 ip dhcp pool POOL network 192.168.1.0 /24 default-router 192.168.1.1 dns-server 8.8.8.8 4.2.2.2
56
Configure NAT overload to the Fa0/1 interface IP for all RFC 1918 addresses behind Fa0/0.
access-list 1 permit 10.0.0.0 0.255.255.255 access-list 1 permit 172.16.0.0 0.15.255.255 access-list 1 permit 192.168.0.0 0.0.255.255 interface Fa0/0 ip nat inside interface Fa0/1 ip nat outside ip nat inside source list 1 interface Fa0/1 overload
57
Configure a NAT pool with the four IP address 200.1.1.2 through 200.1.1.5.
ip nat pool NAME 200.1.1.2 200.1.1.5 prefix-length 24
58
Configure a static NAT so that | the host 10.50.1.20 connected to Fa0/0 will appear with a source of 200.2.1.1 to the ISP on Fa0/1.
interface Fa0/0 ip nat inside interface Fa0/1 ip nat outside ip nat inside source static 10.50.1.20 200.2.1.1
59
What is the IPv6 broadcast address?
Trick question there is no IPv6 broadcast.
60
Describe EUI-64
first 24-bits of MAC, followed by FFFE, followed by second 24-bits of MAC.
61
List major IPv6 address type prefixes
Global Unicast - 2000::/3 Unique Local - FD00::/8 (FC00::/7 with FC00::/8 undefined) Link Local - FE80::/10 Multicast -FF00::/8
62
What is used in the host portion of a link local address on a Cisco router.
Modified EUI-64 address
63
Command to turn off all IPv6 router advertisements both solicited and unsolicited
IPv6 nd ra suppress all | note: 'all' keyword introduced in 15.1(3)T3
64
What command enables Stateless Address Auto Configuration on interfaces with IPv6 addresses?
ipv6 unicast-routing
65
Configure ipv6 route to network 2001:56::/64 with next-hop 2001:210::1
IPv6 route 2001:56::/4 2001:210::1
66
Syslog severities are logged from 0 to _____. ____ is the most severe level while ___ is the least.
7 | 0, 7
67
Command to enable seeing console messages on telnet/ssh vty
terminal monitor
68
Command to send syslog messages to another host
logging host x.x.x.x
69
Command to set daylight savings time
clock summer-time XX recurring
70
Commands to configure NTP 1) Listen for broadcasts 2) Listen for multicasts 3) Poll server directly
1) interface: ntp broadcast client 2) interface: ntp multicast client 3) global: ntp server x.x.x.x
71
List the four major configuration registers
0x2100 ROMMON 0x2101 RXBOOT 0x2102 Boot Normally 0x2142 Ignore NVRAM
72
List where IOS looks for a bootable images in order
Images specified by "boot system" commands First IOS image in flash Broadcast for a TFTP server
73
When in ROMMON how to set to boot with no config
confreg 0x2142
74
Configure port security to re-learn MAC addresses every 10 minutes
switchport port-security aging time 10
75
Configure a ROAS subinterface for Fa0/0 VLAN 2
interface Fa0/0.2 encapsulation dot1q 2 ip address x.x.x.x
76
Configure logging to send only warnings level 4 and below to syslog hosts
logging trap warnings
77
Command to set time zone
clock timezone XXX -n
78
List steps to obtain and install a license on an IOS 15 device
1 - Purchase license and receive PAK key 2 - Get license file from CLM or www.cisco.com/go/license using UDI 3 - Use the CLI to install the .lic file
79
How do you find the UDI and what is it a combination of
show license udi | It is a combination of the product id (PID) and SN. (ex: CISCO2911/K9FTX1524PIRE
80
Command to show licenses
show license all | show license detail
81
Command to show features enabled on device
show license feature
82
Install license
license install flash0:licensefile.lic
83
Backup license
license save flash:filename
84
Unistall a license
``` license boot module x x x disable do reload license clear x conf t no license boot module x x x disable do reload ```
85
What command sets the local router as an authoritative time source
ntp master
86
What commands show cdp neighbor information
``` show cdp show cdp entry * show cdp neighbors show cdp neighbors detail show cdp interface show cdp traffic ```
87
How to configure the router to generate a link-local IPv6 address
Either statically assign an IPv6 address or autoconfig. Link-local will be generated at the same time.
88
What is another name for ROMMON mode?
Router diagnostic mode (maybe?)
89
List and describe DHCP message types
DHCPDiscover - First packet sent by host DHCPOffer - Response from server includes IP, mask, gateway, and other information. DHCPRequest - This is the response to the DHCPOffer or simply a request if renewing DHCPDecline - The client determines the offered configuration parameters are invalid and sends a decline message. DHCPAck - This comes from the server to acknowledge the request DHCPNak - This comes from the server if DHCPRequest has an unavailable IP DHCPRelease - The client sends this when it no longer needs the lease. DHCPInform - This is used to obtain other network information if the client already has an IP manually configured or obtained elsewhere.
90
When running a classful routing protocol what command allows it to use the default route even if it already knows some routes in a major network?
ip classless
91
How many NTP stratum levels can be used?
16
92
What should be included in a login banner?
- Notice that use is permitted only by authorized personnel - Notice that unauthorized use is unlawful and may be prosecuted - Notice that access and use may be monitored and logged for use in court - It should not include words like 'welcome'
93
List and describe colors of the system LED on Cisco switches
off - no power solid green - operating normally solid amber - not operating normally
94
List Cisco password best practices
- 10 characters - Must begin with alphabetic character - Include U/L/N/S - No dictionary words even as part of password
95
What command disables cdp on a router?
no cdp run
96
List device type codes for CDP
``` R - Router T - Transparent Bridge S - Switch H - Host r - Repeater P - Phone D - Remote M - Two-port Mac Relay ```
97
List device type codes for LLDP
``` (R) Router (B) Bridge (T) Telephone (C) DOCSIS Cable Device (W) WLAN Access Point (P) Repeater (S) Station (O) Other ```
98
What is the mac address-table default timeout. Bonus, how do you change it?
5 minutes mac address-table aging time ss
99
Configure arp timeout
interface: arp timeout ss
100
View arp timeout
show interfaces
101
What is the arp timeout default?
4 hours
102
View CAM table timeout
show mac address-table aging
103
What DHCP configuration command is used to provide phones or other hosts that need a tftp server that address?
next-server x.x.x.x
104
What is equivalent to ntpq -p
show ntp associations
105
How to tell if the clock is synchronized
No asterik and/or 'show ntp status'
106
How to find ntp protocol or bad version packets?
show ntp packets
107
Command to verify md5 hash of file
verify /md5 filesystem:filename [hash]
108
List SYSLOG level names with their associated numbers
``` Emergency - 0 Alert - 1 Critical - 2 Error - 3 Warning - 4 Notification - 5 Informational - 6 Debugging - 7 ```
109
Command to suppress CDPv2 advertisements
no cdp advertise-v2
110
What OSI layer includes SCP and service requests
Session Layer

Computer Networking (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions