Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
65 Cards in this Set
- Front
- Back
|
How to set up SSH on a router with hostmane CorpR1 in domain example.com?
|
Router>enable
Router#config t Router(config)#hostmane CorpR1 CorpR1(config)#ip domain-name example.com CorpR1(config)#crypto key generate rsa general-keys modulus 1024 CorpR1(config)#line vty 0 4 CorpR1(config-line)#transport input ssh |
|
|
What command would you use to troubleshoot a serial link problem?
|
show interface serial 0
|
|
|
If you type "show interface serial 0" and you see "up, line protocol is down" what layer is having a problem?
|
Data Link layer problem
|
|
|
If you type "show interface serial 0" and you see "down, line protocol is down" what layer is having a problem?
|
Physical layer problem
|
|
|
What do you see when you type "show interfaces"?
|
statistics for the interfaces on the router
whether they are shut down the IP address of each interface |
|
|
What is the sequence of powering on a router?
|
POST
IOS loaded from flash startup-config loaded from NVRAM |
|
|
What does "show version" provide?
|
basic configuration of the system's hardware and software version
names and sources of configuration files "config-register" setting boot images |
|
|
How do you set the hostname of a router to CorpR2?
|
enable
config t hostmane CorpR2 |
|
|
What does config-register 0x2102 mean?
|
default boot setting tells the router to look for boot sequence in NVRAM
|
|
|
This command will erase the configuration of a router.
|
erase startup-config
|
|
|
This will verify RIP routing.
|
show ip route
|
|
|
Advantages of RIPv2 over RIPv1
|
multicasts
sends subnet mask information with updates supports classless networks supports discontiguous networks supports authentication |
|
|
Command used to stop RIP routing updates from exiting out an interface
|
Router(config)#passive-interface s0
|
|
|
Class B private address range
|
172.16.0.0 through 172.31.255.255
|
|
|
Class C private address range
|
192.168.0.0 through 192.168.255.255
|
|
|
Class A private address range
|
10.0.0.0 through 10.255.255.255
|
|
|
OSI layers
|
7. Application
6. Presentation 5. Session 4. Transport 3. Network 2. Data Link 1. Physical |
|
|
Function of the Transport layer
|
provides segmentation, sequencing, and virtual circuits
|
|
|
Function of the Network layer
|
provides logical network addressing and routing through and internetwork
|
|
|
Function of the Data Link layer
|
provides framing and placing of data on the network medium
|
|
|
Function of the Physical layer
|
responsible for taking 1s and 0s and encoding the into a digital signal for transmission on the network
|
|
|
the three layers of the Cisco three-layer model
|
core, distribution, access layers
|
|
|
shows RIP routing updates
|
debug ip rip
|
|
|
Used by RIPv1 and RIPv2 to prevent routing loops
|
split horizon and holddown timers are used by RIPv1 and RIPv2 for this purpose
|
|
|
the command "show cdp neighbors" works at this layer
|
data link layer command that shows:
-device ID -local interface -holdtime -capability -platform -port ID (remote interface) |
|
|
PPP Data Link layer protocols
|
NCP - Network Control Protocol
LCP - Link Control Protocol HDLC - High-Level Data-Link Control |
|
|
WAN Data Link encapsulations
|
HDLC
PPP Frame Relay |
|
|
PPP authentication methods
|
CHAP
PAP |
|
|
WAN connection types
|
Packet switching
Circuit switching Leased Lines |
|
|
PPP phases of session establishment
|
link establishment
authentication phases Network layer protocol phase |
|
|
TCP/IP Model
|
Application (App, Presentaion, Session)
Transport (Transport) Internet (Network) Network Interface (Data Link, Physical) |
|
|
Protocol Data Units
|
Application (Data)
Presentation (Data) Session (Data) Transport (Segment) Network (Packet) Data Link (Frame) Physical (bits) Did Sally Pack For Bermuda |
|
|
MAC address characteristics
|
12 valid hex chars
first 6 are OUI |
|
|
Layer 2 protocols
|
Ethernet
Frame Relay PPP HDLC CDP |
|
|
Layer 3 protocols
|
IP, IPX, ICMP
OSPF,IGRP,EIGRP,RIP,IS-IS ARP,RARP |
|
|
SNMP port
|
161 UDP
|
|
|
NTP port
|
123 UDP
|
|
|
TFTP port
|
69 UDP
|
|
|
DNS port
|
53 TCP, UDP
|
|
|
DHCP
|
67, 68 UDP
|
|
|
Telnet port
|
23 TCP
|
|
|
FTP port
|
20,21 TCP
|
|
|
NNTP
|
119 TCP
|
|
|
PAR
Positive Acknowledgement & Retransmission |
1. Timer started by sender. Segment retransmitted if timer expires before acknowledgement is received.
2. Sender keeps record of all segments sent and expects acknowledgement of each one. 3. Receiving device acknowledges receipt of a segment by sending a segment back indicating next sequence number it expects. |
|
|
Transport layer protocols
|
TCP UDP
|
|
|
Application Layer protocols
|
HTTP, FTP, SMTP, POP3, NTP, SNMP, TFTP, DNS, DHCP, Telnet
|
|
|
802.3ab
|
1000-BaseT
1000Mbps Full Duplex UTP |
|
|
Anatomy of a collision
|
1. Jam signal sent
2. All hosts stop transmitting 3. All host run backoff algorithm |
|
|
Flash memory stores it
|
IOS is stored here
|
|
|
NVRAM stores it
|
startup-config is stored here
|
|
|
0x2142
|
ignores startup config
used for password recovery |
|
|
0x2101
|
boots into ROM RxBoot mode (able to connect to a TFTP server to download an IOS to flash)
|
|
|
0x2100
|
boots into ROMMON (ROM monitor mode)
|
|
|
0x2102
|
checks NVRAM for "boot system" commands
|
|
|
Router switch boot sequence
|
1. POST
2. Locate IOS 3. Load IOS 4. Locate configuration 5. Load configuration |
|
|
WAN serial encapsulations
|
HDLC
PPP Frame Relay |
|
|
Frame Relay encapsulations
|
Cisco (default)
IETF |
|
|
LMI types
Link Management Interface |
Cisco (default)
ANSI Q.933a |
|
|
Admiistrative Distances
|
Routing Source / Administrative Distance
Connected / 0 Static / 1 EIGRP (internal) / 90 OSPF / 110 RIP / 120 EIGRP (external) / 170 |
|
|
Example of an Availability security issue
|
(D)DOS attacks
|
|
|
Example of an Integrity security issue
|
Man-in-the-middle attacks
|
|
|
Example of a Confidentiality security issue
|
packet capturing and replaying
|
|
|
sub-interface types
|
point-to-point (split horizon)
multipoint |
|
|
Permanent Virtual Connection (PVC) states
|
Active
Inactive Invalid (Deleted?) |
|
|
PPP components
|
Compression
Callback Multilink Authentication |
