TERMS TO GET DOWN Flashcards
ARP
Resolves a MAC address using the IP address through a ARP broadcast
POP3
(Post Office Protocol)
- used to retrieve email from mail servers by email clients.
IGMP
(Internet Group Management Protocol)
- defines host groups, which then allows them to receive multicasts for their groups.
SNMP
(Simple Network Management Protocol)
- helps to manage complex networks by letting hosts exchange information with each other, which then can be retrieved by management software that can be used to monitor and manage the network.
SMTP
(Simple Mail Transfer Protocol)
- used to send mail between mail servers
RARP
Resolves an IP address by using the MAC address through a RARP broadcast
OSPF
(Open Shortest Path First)
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RIP
(Routing Information Protocol)
- RIPv2 uses multicasts sent to the address 224.0.0.9
- Hop count is used as the metric. Maximum of 15 hops
- Can maintain up to 6 multiple paths to a network, only if the costs are the same. Support for 4 equal-cost routes is the default.
- Routers automatically share routing info with other routers.
- Less administration required.
- For small-medium networks
IGRP
?
What is the purpose for assigning an IP address on a switch?
A. provides local hosts with a default gateway address
B. allows remote management of the switch
C. allows the switch to respond to ARP requests between two hosts
D. ensures that hosts on the same LAN can communicate with each other
B. allows remote management of the switch
Which two statements describe the IP address 10.16.3.65/23? (Choose two.)
A. The subnet address is 10.16.3.0 255.255.254.0.
B. The lowest host address in the subnet is 10.16.2.1 255.255.254.0.
C. The last valid host address in the subnet is 10.16.2.254 255.255.254.0
D. The broadcast address of the subnet is 10.16.3.255 255.255.254.0.
E. The network is not subnetted.
BD
What two things does a router do when it forwards a packet? (Choose two.)
A. switches the packet to the appropriate outgoing interfaces
B. computes the destination host address
C. determines the next hop on the path
D. updates the destination IP address
E. forwards ARP requests
AC
Which statements accurately describe CDP? (Choose three.)
A. CDP is an IEEE standard protocol.
B. CDP is a Cisco proprietary protocol.
C. CDP is a datalink layer protocol.
D. CDP is a network layer protocol.
E. CDP can discover directly connected neighboring Cisco devices.
F. CDP can discover Cisco devices that are not directly connected.
BCE
Which statements are true regarding ICMP packets? (Choose two.)
A. They acknowledge receipt of TCP segments.
B. They guarantee datagram delivery.
C. TRACERT uses ICMP packets.
D. They are encapsulated within IP datagrams.
E. They are encapsulated within UDP datagrams.
CD
What must occur before a workstation can exchange HTTP packets with a web server?
A. A UDP connection must be established between the workstation and its default gateway.
B. A UDP connection must be established between the workstation and the web server.
C. A TCP connection must be established between the workstation and its default gateway.
D. A TCP connection must be established between the workstation and the web server.
E. An ICMP connection must be established between the workstation and its default gateway.
F. An ICMP connection must be established between the workstation and the web server.
D
1000BaseLX
Uses fiber optic cabling+LC connectors and supports more than 550 meters.
1000BaseSX
Uses fiber optic cables and supports up to 550 meters.
1000BaseCX
Uses copper cables and supports up to 25 meters, typically used in wiring closets.
CSU/DSU
(Channel Service Unit/Data Service Unit)
-Physical layer device used in wide area networks to convert the CPE digital signals to what is understood by the provider’s switch.
-RJ-48 connector for integrated CSU/DSU routers,
DB-60 connector for single port routers, and
Smart Serial connector for two-port routers
CPE
(Customer Premises Equipment)
-Devices such as a telephone
BootP
(Bootstrap Protocol)
- Used by diskless hosts to get an IP address from a Bootstrap server
WIC
(WAN Interface Card)
-2 port WIC uses Smart Serial Cables, 1 port WIC uses a DB-60 connector
DTE
(Data Terminal Equipment)
- Usually a customer device: router or computer
- NO clock rate
DCE
(Data Communications Equipment)
- Usually the Service Provider Device: Cable Modem, DSL Modem, CSU/DSU
- Provides the Clock Rate
Telnet
- Establishes a remote connection with a destination device
- A successful test verifies Application-layer connectivity. Because Telnet relies on lower-layer protocols, a successful Telnet session also verifies Network-layer and TCP/IP configuration
- A successful Telnet test opens a remote connection to the target device
arp -d
Clears ARP cache
arp - a
Lists ARP cache
Straight-through Cable
Pin Position: 1 -- 1 2 -- 2 3 -- 3 6 -- 6
Crossover Cable
Pin Position: 1 -- 3 2 -- 6 3 -- 1 6 -- 2
Auto-MDI/MDIX
A feature newer switches have to determine whether to use Straight-through/Crossover and the internally change the sending and receiving pin positions.
AUI
(Attachment Unit Interface)
- Designed to connect External Transceiver for conversion to a specific media type (e.g. coaxial or fiber optic)
- Connector: DB-15 / DIX interface
Switch Interface:
Line Status - Down
Protocol - Down
A Physical Layer problem
Switch Interface:
Line Status - Up
Protocol Status - Down
Data Link layer connection/communication problem
APIPA
Automatic address assignment without DHCP.
Addresses are assigned onto the 169.254.0.0 255.255.0.0 network
Configure IP address to a Switch
- Interface vlan 1
- IP address A.B.C.D
- no shutdown
Get info about neighboring devices
show cdp neighbor detail
Order of DNS Name resolution of Router
- Static DNS entries
2. DNS server query (if enabled)
Order of DNS Name resolution of Workstation
- Local DNS cache
- HOSTS file
- DNS server query (Primary)
- DNS server query (Secondary)
Disable/Enable the broadcast name resolution of host names
no ip domain-lookup / ip domain-lookup
Display known IP hosts
show hosts
show Routing Table
show ip route
Routing Protocol
Shares info about known networks
Routed Protocol
Routes packets
Setup a default route
ip route 0.0.0.0 0.0.0.0
CDP
(Cisco Discovery Protocol)
- Detects directly connected Cisco devices
- Must be enabled by both devices
- Enabled by default
See IP address and Layer 1 and 2 info of an interface
- show protocols
- show ip interface
Nslookup
Resolves the IP address of a host name. Also displays resolution-related information such as the DNS server used for the lookup request
ipconfig
Displays IP configuration info on a workstation
VoIP
- Protocol that transmits voice over the Internet or other packet switched network.
- how: IP protocols carry Telephony signals as digital audio encapsulated in a data packet stream over IP.
- Typically implemented using switches with additional configuration required on both switches+routers to ensure VoIP packets of acceptable quality.
Access Link
One VLAN
Trunk Links
Multiple VLANs
VLAN
- Broadcast domains defined by switch port, not network address
- Switches come with default VLANs
- All ports are members of VLAN 1 by default
- Switches compared to Routers: are cheaper, easier to administer, and offer higher performance
- Routers are still needed to: Filter WAN traffic, route between separate networks, and rote packets between VLANs
- In a VLAN switched network, use 802.1q ,OR use devices of the same vendor
Define a VLAN
vlan
Assign ports to a VLAN
switchport access vlan
List VLANs
show vlan / show vlan brief
Name a VLAN
In vlan config mode, # name WORD
Trunking
- Connecting two switches together
- Trunk ports usually use Gigabit ports but can use any ports
ISL
(Inter-Switch Link)
- Cisco proprietary trunking protocol
- ISL tags each frame with the VLAN ID
802.1q
- IEEE standard for trunking, therefore is accepted by a wide range of devices
- VLAN 1 frames are NOT tagged. All OTHER frames are tagged.
DTP
(Dynamic Trunking Protocol)
- Allow switches to automatically detect and configure trunk ports
Show interface trunking info
show interface trunk / show interface trunk
switchport mode access
- Disables trunking configuration on the port
- the Port acts as a single VLAN interface that sends/receives non-tagged frames
switchport mode dynamic desirable
- If switch is connected, the desired trunking protocol will be attempted to be used
- If switch is NOT connected, it will act as a normal port
switchport mode dynamic auto
- Enables automatic trunking discovery and configuration
- The switch uses DTP to configure trunking
switchport mode trunk
- Enables unconditional trunking on the interface
- DTP will NOT be used
switchport trunk native vlan
- Configures the VLAN that is sending and receiving untagged traffic on the trunk port when the interface is in 802.1q trunking mode
- Both interfaces need to have the same Native VLAN or traffic can’t be transmitted correctly on the trunk
switchport trunk allowed vlan all
trunk allowed vlan add
trunk allowed vlan remove
Set which VLANs are allowed to communicate over the trunk.
VTP
(VLAN Trunking Protocol)
- Propagates configuration changes to other switches in a multi-switch network
The 3 Types of Routing Protocols
- Distance Vector
- Link State
- Hybrid
Distance Vector
- Peer-to-peer structure
- Entire routing tables sent at regular intervals
- Updates only sent to neighboring routers
- Susceptible to routing loops
- Long convergence time
- Split horizon, route poisoning, hold down timers, and static routes prevent routing loops
Distance Vector Method: Split Horizon
- Remembers where information comes from and does not report route information back to routers on that path
Distance Vector Method: Poison Reverse
- Routers advertise an unreachable path when sending route info back to the path they heard it from
Distance Vector Method: Triggered Updates
(also known as Flash Updates)
- Routers that receive updated information broadcast those changes immediately, instead of waiting for next reporting interval
Distance Vector Method: Hold-downs
- Routers hold an update that reinstates an expired link for a period of time
Link State
- Hierarchical structure
- No routing loops and Less convergence
- Flooding (routers broadcast LSPs to all routers)
- LSPs are sent in regular intervals when there’s a new neighbor, when a neighbor has gone down, or the cost to a neighbor has changed
- Routers send route info only about their own links
- “Hello” packets are sent to discover new neighbors
- Constructs a SPF tree logical topology of the network
- Uses areas, time stamps, sequence numbers, aging timers, and designated routers
Hop Count
The number of routers between a source network and the destination network.
Passive Interface
Prevents routing update messages from being sent through the interface.
How to identify DCE interfaces?
show controllers
Formula to find out the number of available addresses
2to the u-2
Formula to find out the number of subnets
2to the b
What are the settings used for a terminal emulation program when connected via a console port?
9600 Baud Data bits = 8 Parity = None Stop bits = 1 Flow Control = None
What are the options for connecting and managing a Cisco device?
Console, Virtual Terminal (VTY), Security Device Manager (SDM)
A _____________ uses a web-based GUI to manage a Cisco device.
Security Device Manager (SDM)
When using a Security Device Manager to manage a device, __________ is the default IP address used.
10.10.10.1
__________is the default username and password when connecting with Security Device Manager.
cisco
A new router may not be completely configured for an SDM connection, so you may need to make _______________ first.
Console connection
What is the pin-out layout in a Rollover Cable?
1-->8 2-->7 3-->6 4-->5 5-->4 6-->3 7-->2 8-->1
What is the pin-out layout of a Straight-through cable?
1–>1
2–>2
3–>3
6–>6
What is the pin-out layout of a Crossover cable?
1–>3
2–>6
3–>1
6–>2
