CompTIA Network+
COMPTIA Network+ Notes
Cables and Connectors
Copper Cables
Shielded vs unshielded
Shielded due to EMI (Electromagnetic Interference)
Shielded Twisted Pair (STP)
Token Ring networks (80’s-90’s)
Replaced by Ethernet
Unshielded Twisted Pair
Less expensive
Lower transmission capabilities
UTP Categories
Cat 1
Phone cable, no data
Cat 2
Limited data, 4mb/s
Cat 3
Longer distances (100m), 10mb/s
Cat 4
16 mb/s
Ethernet UTP Categories
Cat5
100 mb/s “Fast Ethernet”
Cat5e
1gb/s
Cat 6 & 6a
10gb at <50m
1gb at >50m
Coaxial (Coax) Cable
Early LANs
Thick Ethernet (10BASE5)
Thin Ethernet (10BASE2)
Twin-axial (Twinax) Cable
Similar to coax
Two conductors vs one
Cost-efficient
Wiring Standards
Telecommunications Industry Association (TIA)/Electronics Industries Alliance (EIA)
TIA/EIA 568A
TIA/EIA 568B
Sequence for each individual wire
Selecting a Wiring Standard
Residential (usually 568A)
Pre-existing wiring
Project specifications
Internally wired components
Straight-Through Wiring
No difference in functionality
Purely for consistency
Both used for connecting something like a computer to a switch
Crossover Wiring
Adjusting the senders vs the receivers
Identify by examining the two ends
Straight-through vs Crossover Cable Uses
Straight-through
Switch to router
Switch to computer
Hub to computer
Crossover
Switch to switch
Switch to hub
Hub to hub
Router to router
Computer to computer
Singlemode and Multimode Fiber Cabling
Fiber Cabling Construction
Cabling Application Differences
Single mode
Designed to carry a single mode of light at a time
Multimode
Can carry multiple modes of light at a time
Fiber Cabling Cost
Single mode used over longer distances
Suitable to outdoor applications
Multimode used over shorter distances, more suited to indoor applications
Single-mode Fiber Categories
OS1: Indoor applications - 10km (in theory, usually at 2-5km)
Complexes, campuses airports
OS2: Outdoor applications - 200km (in theory)
Telephone lines
Multimode Fiber Categories
OM1 - 10 Gbps up to 33m
OM2 - 10Gbps up to 82m
OM3 - 40 Gbps up to 300m
OM4 - 40 Gbps up to 550m
OM5 - 28 Gbps per channel over 4 channels
Common Cable Connector Types
Cable Connector Components
Ferrule - core of the cable, where light travels through
Connector body - plastic/metal/ceramic structure hold ferrule
Coupling mechanism - physically connecting to interface
Connector Types
Local Connector (LC) (aka Lucent Connector) (aka little connector)
Most common in newer implementations
Very small
Straight Tip (ST)
Round, bayonet connector
Subscriber Connector (SC) (aka square connector)
Can be paired up
Mechanical transfer registered jack (MTRJ)
Only used for multimode fiber
UPC vs APC Connectors
UPC = Ultra-physical contact
Light comes straight through
Fine for most LAN, but sometimes a little light bounces out
APC= Angled physical contact
Light reflects at an angle
Greater chance of all light getting back to source
Registered Jack (RJ Connectors
RJ11
For phones
Up to Six pins
RJ45
8 pins
Standard connectors for UTP
F-Type Connector
Domestic tv equipment
Ground to satellite links
Common Types of Optical Transceivers
Transceiver
Component responsible for converting electrical signals into light for communications over a fiber optic network
About size of a flash drive
Hot-pluggable into things like switches - makes system modular
Small form-factor pluggable (SFP)
Upgraded version of GBIC (gigabit interface converter)
½ volume of GBIC
Data rate 100 MBps - 4Gbits/s
Enhanced form-factor pluggable (SFP+)
Enhanced version of SFP
8 Gbit/s Fibre Channel
10 Gigabit Ethernet & Optical Transport Network
Quad form-factor pluggable (QSFP)
4 channels simultaneously
1 Gbit/s data rate per channel
Good for multiplexing
Enhanced Quad form-factor pluggable (QSFP+)
4 x 10 Gbit/s channels
1 x 40 Gbit/s Ethernet link
SFP or SFP+ ?
SFP is dated, rare to see in use
SFP+ supports greater speed
Not interchangeable in terms of connections
QSFP and QSFP+
QSFP is slower
Both compatible connections and data
Cable Management
Patch Panels
Where all ethernet connections end up so they can be connected centrally
Ex: where all office data ports lead to
Punchdown blocks
Where all cables converge
Cables are stripped down to wire, put through these blocks, then wired through a RJ45 connector to a switch
Cable Trays
Devices that might hang overhead or mounted under the floor so that cables can be run out of the way
Separate tray for power cables and data cables recommended
Uninterruptible Power Supply (UPS)
Power backup and protection against brownouts or surges
Conditions power
Aren't designed for hours of power, used for gracefully shutting things down
Can be a significant source of EMI
Power Management
Keep power cables away from data cables
Copper Ethernet Standards
10BASE-T
10 = 10 Mbps transmission speed
BASE = baseband method of transmission
Uses 100% of the bandwidth of that cable
T = twisted pair
100BASE-TX
100 MBps
X doesn't really matter
CAT5 UTP straight-through cable
1000BASE-T
1 Gbit/s
CAT5e
CAT6/6a
CAT 7
GBASE-T
10GBASE-T (CAT 6, CAT7)
40GBASE-T (currently in development)
Approx 30m limit
Fiber Ethernet Standards
100BASE-FX
“Fast Ethernet” over fiber optic cables
100BASE-SX
Lower cost alternative
Shorter wavelength → shorter distance
S= shorter distance, L= longer distance
1000BASE-SX
Extension of Ethernet standard to gigabit-level network speeds
Uses multimode fiber-optic cabling
220m or 500m depending on cable grade
Cable Grade
Diameter of the core of the cable
1000BASE-LX
Supports distance of up to 5km (requires single-mode fiber)
10GBASE-SR
SR = Short range-standard
30-50m
10GBASE-LR
LR=Long Reach
10km max
Multiplexing
Sending multiple signals at once through a single, more complex signal
Wavelength Division Multiplexing
Divide a single physical cable into channels
Coarse
Uses lower wavelengths (from 1270 nm)
Creates 18 channels (13mn per channel, 7mn between each channel)
Greater distances, more cost effective
Dense
Uses higher wavelength
Increases bandwidth over existing fiber networks
88 channels
Bidirectional Wavelength-division Multiplexing
Used to multiplex numerous carrier signals into one optical fiber
Performed by using various wavelengths
More expensive
Broadband
Transmitting using a wide range of frequencies through one physical cable
Ethernet Switching & Wireless Standards
Data Virtual Local Area Network
Virtual Local Area Network (VLAN)
Logical grouping of devices
Can be configured regardless of computers physical location
VLAN Benefits
Cost-effective
Reduces admin overhead
No extra infrastructure needed except VLAN compatible switchers
Characteristics
Increase number of broadcast domains
Broadcast
Packet that is heard by all systems
Reduces security risks
Improve performance
Design more flexible networks
Make network config easy
LAN Topology
Each computer has to stop what it’s doing and examine the broadcast packet
Interrupting systems for no reason
VLAN Topology
Splits computers into different VLANs, so only the computers in a specific VLAN are interrupted by a broadcast
VLAN Membership
Determining which computers should belong to which VLAN
Static
More common
Manual process
Gives more control
More secure
Dynamic
Based on a mac address
Stays the same regardless of physical location
Requires at least one switch to act a a VLAN Membership Policy Server
Could be more expensive
Better for lots of computers
VLAN Connections
Access link - computer to switch
Trunk link - switch to switch
Trunk Tagging
Identifies VLAN membership across multiple switches
Adding a VLAN “tag” to a signal passing from one switch to another, because the computers don’t have VLAN information, only the switches do
Voice VLAN Configuration
Allocated for VoIP systems
Should prioritize this kind of traffic
Example - MAC Address Mode
Switch can distinguish the PC from the phone by the MAC address, so can then prioritize the the voice packet over the data packet
Voice VLAN Example - VLAN Mode
Voice VLAN Benefits
Ensures VoIP devices are not impeded
Prioritizes voice services
Simplifies network configuration
Voice VLAN Modes
Normal mode
Normal mode has prioritization, but no authentication
Security mode
Can implement a verification of the MAC address of the phone
Will discard packets from phones with no registered MAC address
Ethernet Switching Port Configuration
Duplex Communication
Half-duplex is very rare
Duplex and Speed
Trunk
Where two switches are connected to each other
Port Tagging
The port is expecting to see VLAN info
Link Aggregation Control Protocol (LACP)
Means to combine the bandwidth of multiple physical ports into a single logical port
Implemented for switch to switch or switch to security device config
Not for pc to pc config
Increases reliability
Physical resource allocation
Improved bandwidth
Cost-effective
Port Aggregation Protocol (PAgp)
Specific to cisco
Three values
Auto (passive)
Waiting for desirable to tell it what to do
Desirable (active)
Tells other port what to do, activates PAgp if other port is compatible
On
Always on
Simply enables, no negotiation
Just assumes all ports are on
Flow Control
Reduces packet loss
Little traffic cop, pauses packets when network is congested
Millisecond pause
Port Mirroring
Used for diagnosing errors
Port Security
Prevents unknown devices from forwarding packets
Jumbo Frames
Can be used to optimize data flow
Intentionally violates rules of ethernet
Make sure all devices/applications participating support it
Definitely test, determine if its really worth it
Ethernet Interfaces
Medium Dependent Interface (MDI)
The regular type of cable connecting between pc and switch
Medium Dependent Interface Crossover (MDIX)
Crossover cable from switch to switch
Auto-MDI/MDIX
Port adjusts dynamically between MDI and MDIX depending on what cable plugs in
Media Access Control Address Tables
Media Access Control (MAC) Address
48-bits long
Represented by 2 hexadecimal characters
Coded into network interface upon manufacture
Never changes
Ex
00:AA:19:9A:58:B4
Structure
Organizationally Unique Identifier (OUI)
24 bits long
Allocated to manufacturer by Institute of Electrical and Electronics Engineers (IEEE)
Remaining 24 bits used at vendor’s discretion
MAC Address Operation
MAC address resides in Data Link Layer
Data link layer is layer 2
MAC Sublayer
Logical Link Control (LLC) Sublayer
Media Access Control (MAC) Sublayer
MAC Address Tables
Determines where to forward network traffic on a switch
Displaying MAC Addresses
Windows
Command “Ipconfig/All”
Will display the MAC addresses of all adapters in system
Cisco
Command “Show mac address-table”
See all MAC addresses in the table
Power Over Ethernet
Enables network cables to carry electrical power
Common devices
VoIP phones
Wireless devices
IP cameras
Benefits
Cost savings
Reliability
Scalability
Flexibility
Limitations
Power delivery rates
Transmission distance
Device compatibility
Distances
100 to 1000+ meters
Data only goes to 100m, power can go farther
Specifications
PoE
Uses
VoIP phones
Wireless access points w/ 1 or two antennas
sensors/meters
15.4 W
PoE+
Uses
Moving camera
30W
PoE+
For devices that draw lots of power, eg. complex video conferencing system
Power Supply
Spanning Tree Protocol (STP)
Spanning Tree Protocol (STP)
Protocol used to prevent switching/bridging loops
Works at the data link layer
Based on MAC addresses
Looping
Ethernet frames circulate the network without reaching their destinations
Looping Example
Redundant connections in case of failure
STP Advantage
Simple to use
Wide support
Redundancy
Proven technology
Familiar
STP Disadvantages
I/O limitations
Widespread failure
Bit dated
CSMA/CD Media Access Control Methods
CSMD/CD
Carrier sense multiple access/collision detection
Essence of Ethernet
Collision Detection
Regulates communication
Interconnecting devices can detect when a collision occurs and determine what can be done to correct the issue
CSMA/CD Components
Carrier sense (CS)
Systems won’t just always assume that the physical medium is available
“Listening” to see is the medium is available
Multiple access
Multiple devices are sharing the medium
Collision Detection (CD)
Devices are able to realize that a collision has occurred
CSMA/CD Process
Both systems are trying to send a packet to the same destination at the same time and a collision will occur
Both packets are lost and need to be retransmitted
Devices will stop transmitting and wait a random amount of time before attempting to place their packets on the wire again, which reduces the chance of another collision
Protocols
CSMA/CD
Collision detection
CSMA/CA
Collision avoidance
Tells a device to send out a signal to inform other devices that it’s about to send out a packet
Address Resolution Protocol (ARP)
Address Resolution Protocol (ARP)
IP address → Media Access Control Address (MAC)
Similar to DNS - instead of resolving IP address info to name it resolves it to MAC address
ARP - OSI Model
Works between layers 2 and 3
MAC Address = Layer 2
IP address = Layer 3
Says “this MAC address is with this IP Address”
ARP Example
Examines the IP address and determines if this computer is actually using that IP Address
Can be used to find the MAC address by requesting the IP address, which re
Advantages of ARP
End node discovery
Easily identify MAC addresses
Disadvantages of ARP
Prone to malicious activity
ARP Attacks
Often from inside the system
Man-in-the-middle attacks
Third party involved when only two parties are apparent
Denial of service attacks
Take something down
Flood the system with too many requests
Session hijacking
Take over session to gather data
Neighbor Discovery Protocol
Neighbor Discovery Protocol (NDP)
Used in conjunction with IPv6
IPv6 equivalent of Address Resolution Protocol (ARP)
Responsible for the resolution of IPv6 addresses into valid MAC addresses
Addresses are stored in “neighbor cache”
“Neighbor” refers to all of the addresses that have been discovered and resolved on the same network segment
Neighbor Cache
Device using NDP manage their own neighbor cache
NDP Cache Components
Destination cache
Other standard devices that have been discovered through normal network traffic
Default router list
Stores list of all known routers that are visible to the host device
Prefix cache
Used to manage all network prefixes that apply to the network where the original host resides
Internet Control Message Protocol (ICMP)
Detecting duplicate addresses
Verifying host relevance
Router and prefix detection
Determining transmission parameters
Redirect options
802.11 Standards and Technologies
802.11 Wireless Standards
Speed
Transmission Range
Frequency
Different frequencies are not compatible
Changing frequencies requires replacing the router
802.11
From a IEEE project in Feb of 1980, thus “80” & “2”
IEEE 802.11
Transmission speed of 1-2 Mbps over 2.4 GHz frequency
IEEE 802.11a
Transmission speeds of up to 54 Mbps over 5 GHz frequency
IEEE 802.11b
11 MBps
Backward compatible with 802.11
2.4 GHz
IEEE 802.11g
Up to 54 MBps over 2.4 GHz frequency
Compatible with both original 802.11 and 802.11b
IEEE 802.11ac
Speeds from 433 Mbps to 1.3 Gbps
Only over 5 GHz frequency
IEEE 802.11ax (Wifi 6)
Next gen standard in WiFi technology
Referred to also as AX WiFi
Greater speeds and stability
Up to 14 Gbps using multiplexing channels
Only 5GHz
Why 2.4 GHz at all?
Higher frequencies don’t travel as far
Wireless Frequencies and Ranges
2.4 GHz
Speed
Max speed of 450 to 600 Mbps
Depends on specs of different devices on the WiFi
Range
150 ft indoors
300 ft outdoors
Can go farther than 5GHz
Considerations
Pros
Larger coverage area
Better at penetrating objects
Concrete
Wood
Cons
Lower data rates
Prone to interference
Can become overcrowded
5GHz
Speed
Max 1300 Mbps (1.4 Gbps)
Channels
Multiple non-overlapping channels
Can result in less interference
Benefits
Higher speeds
Clearer signal
Not as susceptible to interference
Disadvantages
Shorter range
Compatibility
Common WiFi Channels
WiFi Channels
2.4GHz = 11 WiFi channels
5GHz = 45 WiFi channels
Channel Designations
WiFi Channels
USA = channels 1-11
Europe = channels 1-13
Japan = 1-14
Each channel overlaps another channel a little bit
Like vibrato wobbles above and below the the actual note, the wave has to cover some distance around the “actual” frequency
Each channel spans 22MHZ
1, 6, 11, 14
Far enough apart that they don't overlap, and so are used most often
Channel Width
Directly affects
Speed
Volume of data
Channel Selection
All devices in the same WiFi network need to use the same channel to transmit and receive data
By default the following channels are used:
Channel 6
Channel 11
All devices need to be on the same channel OR on non-overlapping channels
OR
Channel Configuration
Automatic
Default configuration where the devices detects what is being transmitted and uses the same channel
Good for single WiFi router
Manual
Can be used to segregate one of the WiFi routers to different channel
All devices using that router also need to be manually set to that channel
Wireless Channel Bonding
Channel Bonding
Common in IEEE 802.11
Used to combine different channels
Increases throughput
Channel Bonding Example
Core frequency only occupies 20MHz, but the channel allocates 1 MHz on either side for buffers
Bonded channel is now 40MHz wide and offers better performance
Channel Bonding Popularity
Introduced with 802.11n
Provides additional functionality and increased throughput
2.4 GHz Frequency Band
3 non-overlapping channels
Total width of approximately 70MHz (channels 1 through 11)
Only a single bonded pair of 40 MHz can be configured (channels 1 and 6)
Only a single non-overlapping channel would remain (channel 11)
5 GHz Frequency Band
25 non-overlapping channels
Total width of over 500 MHz
Many more bonded pairs can be configured
Up to 160 MHz in 802.11ac
Very high throughput
Service Set Identifier
Service Set Identifier (SSID)
Used to uniquely name a wireless local area network (WLAN)
The collection of all devices connected to all access points
Basic Service Set (BSS)
Used to form one logical WLAN segment
EX: one wireless access point with a few devices connected to it
Extended Service Set (ESS)
One or more interconnected Basic Service Sets (BSS)
One access point
One station
Used in large environment, e.g. airport terminal or hotel, so that the network name stays the same as the device moves through the space
WiFi Roaming
IT people can isolate traffic as they see fit
Independent Basic Service Set (Ad Hoc)
Simplest IEEE 802.11 network
Can be set without a router if there are two wireless devices that can talk to each other directly
Ad Hoc Mode vs Infrastructure Mode on the router
Infrastructure is when connection goes through the router
Wireless Antenna Types
Antennas
Used to transmit or receive radio
Converts electric power into radio waves
Can be tiny in size to very large structures
Omni-Directional Antennas
Transmit and receive with equal efficiency in all directions
Signals emanate in a sphere
Examples include radio transmission towers, cell phone antennas, WiFi routers
Advantages
Easy to install
Mounted virtually anywhere and in any direction
Disadvantages
Typically have a shorter range due to the signal being spread so broadly
Inefficient
Directional Antennas
Designed to have a narrow directional; signal
By design, there types of antennas work more effectively in some directions compared to others
Advantages
Improves transmission
Improves reception of communications
Reduced interference
Disadvantages
Decreased effective beam width
Directional Antenna Types
Semi-directional
The signal is a 45 - 180 degree signal
Bi-directional
A 45-180 degree signal in front and back
Yagi-Uda Antennas
Arrangements of perpendicular and parallel elements
Highly directional antenna
Used for fixed point-to-point systems
Parabolic Dish Antennas
Use a parabola to focus incoming signals to a point
Common in satellite communications and other long-range, directional applications
Wireless Encryption Solutions
Wired Equivalent Privacy (WEP)
Older encryption algorithm
Secures data across a wireless network
WEP key
Sequence of hexadecimal characters
Characters must match on all devices communicating on a wireless network
Advantages
Interoperability
Useful when connecting older devices
Disadvantages
Can be cracked
Changing the key can be tedious
Wi-Fi Protected Access (WPA)
Developed by Wi-Fi Alliance
Designed to replace WEP
Adopted in 2003
Stronger Encryption
Data integrity
Verify data has not been tampered with or altered
Advantages
Stronger encryption than WEP
Uses Temporal Key Integrity Protocol (TKIP)
Dynamic key changes if necessary
Disadvantages
Proven to be incompatible with some legacy hardware or older operating systems
Wi-Fi Protected Access II (WPA2)
Provides stronger data protection
Provides network access control
Ensures only authorized users can access a wireless network
Provides government grade security
AES encryption algorithm
802.1x-based authentication
Editions
WPA2-Personal
Requires a password
WPA2-Enterprise
Verifies users through a server
Benefits
Compatibility
However, some older equipment may not support it
Security
More advanced encryption
TKIP for interoperability with WPA very difficult to crack without network access
Temporal Key Integrity Protocol (TKIP)
Encryption protocol used for wireless LANs
Improves upon WEP
Original WLAN security protocol
Provides more secure encryption
Encryption method in WPA
TKIP-RC4
Suite of algorithms that allows legacy WLAN equipment to upgrade to TKIP
Without replacing any hardware
Uses WEP programming
Additional code is “wrapped” at both the beginning and end to modify and encapsulate it
RC4 stream encryption used as its basis
Data packets are encrypted with a unique encryption key
TKIP uses four algorithms to increase key strength
TKIP-RC4/AES-CCMP
Does not address all security issues for WLANs
May not be efficient enough for certain data transmission
Government
Sensitive corporate
AES-CCMP
Higher level of security
Approved for government use
May require hardware upgrades
Common Cellular Technologies
GSM
Global System for Mobile communication (GSM)
Digital mobile telephony system
Represents over 90% of all global mobile connections
Operates at one of two frequencies
900 MHz
1800 MHz
Digitizes and compresses data prior to sending down a channel
TDMA
Time Division multiple access (TDMA)
Facilitates multiple users sharing the same media
Cellular channels are divided into three time slots
Used by
Global System for Mobile communications (GSM)
Digital-Advanced Mobile Phone Service (D-AMPS)
Personal Digital Cellular (PDC)
Out of date by today’s standards
CDMA
Code Division Multiple Access (CDMA)
Used in second-generation (2G) and third generation (3G) wireless communications
Form of multiplexing
Allows numerous signals on a single transmission channel
Commonly used 800 MHz and 1.9 GHz
LTE (4G)
Long-term Evolution
Uses orthogonal frequency division multiple access (OFDMA)
Uses frequency ranges to create separate channels
5G
Still being developed
Gbps
Lower latency (near real-time)
Perform remote operations
Specific device support
MU-MIMO Technology
MIMO
Multiple input, multiple output (MIMO)
Antenna technology for wireless communication
Sends multiple signals at once and uses and array of antennas
Antennas at each end of the circuit are combined to help:
Minimize errors
Optimize data speed
Support
802.11n
802.11ac
Single session
Supports multiple devices in separate sessions
Each device must take turns
Not as fast
MU-MIMO
Multi-user multiple input multiple output (MU-MIMO)
Enhanced form of MIMO technology
Simultaneous communication with multiple devices
Significant performance enhancement
Devices no longer have to wait their turn
MU-MIMO Example
802.11ac wireless specification
Increased theoretical maximum wireless speeds ranging from 3.47 Gbps to 6.93 Gbps
Network Troubleshooting Methodologies and Tools
Identifying the Problem
Identifying the Problem
Troubleshooting
Can be challenging
Requires consistent approach
Methodology
Solutions requires understanding what the problem is
Gathering Information
Physical problems
Appropriate connections
Identifying Symptoms
What is the problem showing?
What is and isn’t connected?
Questioning Users
Affecting one vs affecting others
Determining Changes
What has changed?
Could changes be the cause of the problem?
Duplicating the problem
Attempting to recreate
Document steps
Approach Problems Individually
Isolate and address
Narrow scope
Start small and work your way out
Establishing the Cause
Establishing the Cause
Ensures permanent fix
Reduces chances of symptoms reappearing
List potential causes
Prioritize and determine likelihood
Eliminate and focus in
Questioning
Start with obvious questions
Easiest solution is often right
Considering multiple approaches
Start at layer one and move up
Divide and conquer
Assign possible causes to different teams
Test and implement multiple possible solutions
Testing Techniques
Testing Techniques
Answer not always obvious
Establish
Test
Establishing a theory
Question the obvious → gather information
Validating
Test and confirm
Determining next steps
Look for different cause
Establish new theory
Escalate
Reestablish and Escalate
Test new theories
Validate and verify
Escalate
Identifying Potential Effects
Identifying potential effects
Formulate plan to identify impacts of solution
Planning consideration
Timing
Workarounds
Effects of workarounds
Establishing the plan
Step-by-step
Include possible repercussions
Attempting alternatives
Retrace steps
Look at alternative options
Sharing results
Lessons learned
What happened
Why
Resolving Problems
Resolving problems
Verify authority
Issues outside your scope
Lack of permission to implement
Escalating problems
Include all details
Avoid rework
Escalation parameters
Typically tiered structure
Vary from organization to organization
Start with closest resources
Resolving at the right level
Escalate to the next level
Resolve or escalate to next higher level
Expectations
Resolve within your expertise
Iterative experiences
Verifying System Functionality
Verifying system functionality
Verify that solution corrected the problem
Key Considerations
Confirm original issue resolved
Additional considerations
Confirm no new issues exist
Preventative measures considerations
What can be avoided?
Mitigating
What can be mitigated?
Documentation Processes
Documentation Processes
Update
Create new
Documentation Benefits
Used in future instances
Saves time
Key Documentation Elements
Initial problem
Date and time
Who reported problem
Scope
Symptoms
Corrective actions
Outcomes
Ensuring complete documentation
What you tried
What failed
Specifications and Limitations
Specifications and Limitations
Throughput
How much data is transferred
Bandwidth
How much data could theoretically be transferred
Understanding speed
Measures network performance
How fast packets or units of data travel
Slow speed = lag
Understanding throughput
Measured in bits or data per second
Packet arrival
Slow throughput indicators
Packet loss
Latency
Measured in time based value, i.e. seconds
Jitter
Variation of latency
Optimizing throughput
Use wired connection
Reboot network
Close bandwidth-intensive applications
Disable firewall
Go around faulty network hardware
Consult resources
Bandwidth considerations
Maximum transfer throughput
Measured in bit, megabits, or gigabits per second
Does not change speed
Monitoring provides valuable information
Ensures enough bandwidth
Optimizing bandwidth
Use QoS settings
Use cloud-based applications
Eliminating non-essential traffic
Conduct efficient backups/updates