network+

Multipoint Generic Routing Encapsulation (mGRE)

- provides comparable functionality to GRE but in a multipoint environment. - is highly effective in a hub-spoke configuration. - used in conjunction with both the IPSec protocol and Dynamic Multipoint Virtual Private Network (DMVPN).

What's the purpose of Network Address Translation (NAT)?

it's like a temp leased IP address. A device on the network without a legitimate IP is trying to send data so the router will let it borrow its own IP so the device can connect to the internet.

Distance Vector

measures hops to the destination

Maximum Tolerable Downtime (MTD)

metric states the requirement for a business function. Downtime is calculated from the sum of scheduled service intervals (Agreed Service Time) plus unplanned outages over the period.

Class License A

0-126 /8

CompTIA troubleshooting methodology

1. identify problem 2. establish a theory of probable cause 3. test theory 4. establish a plan of action

Loopback Address

127.0.0.1 ::1

Class License B

128-191 /16

how many bytes in the header of a PDU?

18

Class License C

192-223 /24

what's the min/max size of a data payload?

64-1500 bytes

Protocol Data Unit (PDU)

A chunk of data

Storage Area Network (SAN)

A dedicated network storage facility that provides access to data storage over a high-speed network.

Pointer record (PTR)

A record that points IP addresses to host names in a Reverse Lookup Zone.

warm site

A remote site that contains computer equipment but does not have active Internet or telecommunication facilities, and does not have backups of data.

Multiprotocol Label Switching (MPLS)

A router feature that labels certain data to use a desired connection. It works with any type of packet switching (even Ethernet) to force certain types of data to use a certain path.

cold site

A separate facility that does not have any computer equipment, but is a place where employees can move after a disaster

Site-to-site VPN

A virtual private network in which multiple sites can connect to other sites over the Internet.

169.254.x.x

APIPA address (caused because the DHCP is down)

what kind of error can you expect from interference?

CRC error

what does a proxy server do?

Caches frequently accessed internet data, act as a web security gateway, and is a content filter.

QSFP (quad small form-factor pluggable)

Complies with the 802.3ba standard, squeezing four channels in a single transceiver and supporting data rates up to 40 Gbps (4 x 10 Gbps).

What protocol dynamically assigns an IP address to devices or nodes?

DHCP - windows BOOTP - linux

How does the TCP/IP protocol suite resolve the machine hardware address of the target IP if the target IP is on a remote network?

Determine the MAC address of the default gateway using ARP cache

QSFP+

Generally the same technology as QSFP while supporting data rates over 40 Gbps.

Protocols at Level 7

HTTP, SMTP, and FTP

Link Aggregation Control Protocol (LACP)

IEEE specification of certain features and options to automate the negotiation, management, load balancing, and failure modes of aggregated ports.

Mail Exchanger (MX)

Identifies an email server for the domain

State of Authority (SOA)

Identifies the primary DNS name server that is authoritative for the zone and resolves names

Fiber Optics: MMO and SMO

MMO uses LED SMO uses lasers

Coaxial Cable

Made of a single copper wire and insulation. Older cables use RG-59 and modern ones use RG-6.

Plenum-rated cable

Meet the necessary fire safety requirements. Uses treated PVC or Fluorinated Ethylene Polymer (FEP). Under the US National Electrical Code (NEC) is marked CMP/MMP.

Devices that operate at Layer 2

NICs, bridge, switch, wireless APs

what could a "ICMP Time Exceeded" error message be caused by?

Routing Loops

Clientless VPN

Provides remote access services without requiring a host client. Typically uses web browsers to implement Remote Desktop/VPN connection

which remote protocol uses a GUI?

RDP (tcp over port 3389)

Name Server (NS)

Records identify authoritative DNS name servers for the zone

Canonical Name (CNAME)

Represents an alias for a host

Mean Time Between Failures (MTBF)

is for repairable Calculation is total time (devices x hours) divided by the number of failures

How do you convert binary number to a number we can read?

Start with writing out 128 and divide by 2 until you're left with 1. underneath write the binary number one to one add up the 1s the sum is the converted number

Text (TXT)

Stores any free form text that may be needed to support other network services

An internet user types a fully qualified domain name (FQDN) into the URL bar of the Google Chrome web browser. Chrome then checks its local cache for the correct mapping before querying the local name server. Evaluate the role of the Chrome web browser in this scenario.

Stub resolver

AAAA record

The IPv6 DNS host record is referred to as a(n):

Mean Time To Repair (MTTR)

The average amount of time required to repair a device. Calculated by taking the total repair time and dividing it by the number of incidents

Basic Service Set Identifier (BSSID)

The media access control (MAC) address of a wireless access point (AP)

Demarcation Point

The point at which communication lines enter a customer's premises. Sometimes shortened to demarc

Link Aggregation

The seamless combination of multiple network interfaces or ports to act as one logical interface.

what are some characteristics of Collision Detection (CD)?

Utilizes half duplex Instant termination upon CD

Routing Information Protocol (RIP)

a distance vector routing protocol. RIP only considers a single metric to select the optimal path to a given destination network, by selecting the one with the lowest hop count (distance). also see, EIGRP

physical access control system (PACS)

a network of monitored locks, intruder alarms, and video surveillance cameras.

Switched Port Analyzer (SPAN)/mirror port

a sensor is attached to a specially configured port on the switch that receives copies of frames addressed to nominate access ports

EIA 568

aka commercial building telecommunications wiring standard, help businesses apply best practices, plan their infrastructure requirements, and ensure return on their investment

Recover Point Objective (RPO)

amount of data a company is willing to reenter or potentially lose

Enhanced IGRP (EIGRP)

an advanced distance-vector or hybrid routing protocol similar to RIP that uses a metric composed of administrator-weighted elements, such as bandwidth and delay.

If a switch goes down do all users or an individual user get shut down?

an individual user

medium aggressive setting

best for clients that exists within the range of several APs

Cable tester

can be used to check that the cable pins are functioning properly

Link Aggregation Control Protocol (LACP)

can be used to detect configuration errors and recover from the failure of one of the physical links.

At what layer of the OSI model are all hosts identified by a specific MAC address?

data link (layer 2)

Mean Time To Failure (MTTF)

for non repairables Calculation is the total time (devices x hours) divided by the number of devices

What do you use RJ-45 Crimps for?

for patch cables

T568A Wiring Order

from 1-8 green stripe, green solid, orange stripe, blue solid, blue stripe, orange solid, brown stripe, brown solid

T568B Wiring Order

from 1-8 orange stripe, orange solid, green stripe, blue solid, blue stripe, green solid, brown stripe, brown solid

What do you use 110-punch downs for?

horizontal runs

what is a logical topology and what layer concerns this?

how data flows from hosts to hosts and the data link layer 2

Service record (SRV)

identifies a record that is providing a network service or protocol (often used to locate VoIP or media services)

send/receive traffic

involves the movement of information within a system from hosts to endpoints

First Hop Redundancy Protocol (FHRP)

is a computer networking protocol which is designed to protect the default gateway used on a subnetwork by allowing two or more routers to provide backup for that address; in the event of failure of the/an active router, the backup router will take over the address, usually within a few seconds (HSRP, VRRP, or GLBP)

reverse proxy server

provides for protocol-specific inbound traffic. Reverse proxies can publish applications from the corporate network to the Internet in this way.

forwarding proxy server

provides for protocol-specific outbound traffic. A multipurpose forward proxy is one configured with filters for multiple protocol types, such as HTTP, FTP, and SMTP.

polarization

refers to the orientation of waves propagating from a wireless antenna

what do mirrors cause RF signals to do?

reflect

what does glass or water cause RF signals to do?

refract

Traffic Logs

reports produced over a period of time with computing, storage, and network resources stats

high aggressive setting

reserved for critical devices that must always use the strongest connection

what does command "arp -a"do?

show the cached addresses

building automation system (BAS)

smart building for offices and data centers can include PACS, but also network-based configuration and monitoring of heating, ventilation, and air conditioning (HVAC), fire control, power and lighting, and elevators and escalators.

Soutbound

the SDN controller and infrastructure device traffic are southbound API

nontransparent server

the client must be configured with the proxy server address and port number to use it.

Northbound

the interface between SDN applications and the SDN controller is described as the service interface or northbound API

Recover Time Objective (RTO)

the period following a disaster when an individual IT system remain offline. This represents the max amount of time allowed to identify a problem and then perform recovery

east-west

traffic within a data center

devices that operate at Layer 1

transceiver, repeater, hub, media converter, modem

Internet Group Management Protocol (IGMP)

typically used to configure multicast group memberships and IP addresses

A host/record

used to resolve a host name to an IPv4 address

Tone Generator

used to trace and identify a cable from one end to the other

low aggressive setting

wireless clients in isolated areas benefit from this setting because they do not expect to switch channels often

What occurs with mismatched switches?

won't work because they're not the same speed