Advanced Network Diagnostics Tool

Description:

This PowerShell script creates a simple network diagnostics tool. It allows users to perform basic network troubleshooting tasks such as pinging a host, checking DNS resolution, viewing network adapter information, and performing a traceroute. The script demonstrates working with network-related cmdlets, handling user input, and presenting network information in a readable format.

Full Script:

# Advanced Network Diagnostics Tool

# Function to display the menu
function Show-Menu {
    Clear-Host
    Write-Host "=== Advanced Network Diagnostics Tool ===" -ForegroundColor Cyan
    Write-Host "1.  Ping a host"
    Write-Host "2.  Resolve DNS"
    Write-Host "3.  View network adapter information"
    Write-Host "4.  Perform traceroute"
    Write-Host "5.  View open ports"
    Write-Host "6.  Check internet connectivity"
    Write-Host "7.  View IP configuration"
    Write-Host "8.  Perform a network speed test"
    Write-Host "9.  Flush DNS cache"
    Write-Host "10. View routing table"
    Write-Host "11. Exit"
}

# Function to ping a host
function Ping-Host {
    $host_name = Read-Host "Enter the host name or IP address to ping"
    Write-Host "`nPinging $host_name..." -ForegroundColor Yellow
    $result = Test-Connection -ComputerName $host_name -Count 4 -ErrorAction SilentlyContinue
    if ($result) {
        $result | Format-Table @{Name="Source"; Expression={$_.PSComputerName}}, 
                               @{Name="Destination"; Expression={$_.Address}}, 
                               @{Name="IPV4Address"; Expression={$_.IPV4Address}}, 
                               ResponseTime
    } else {
        Write-Host "Unable to reach $host_name" -ForegroundColor Red
    }
}

# Function to resolve DNS
function Resolve-DNSName {
    $dns_name = Read-Host "Enter the domain name to resolve"
    Write-Host "`nResolving $dns_name..." -ForegroundColor Yellow
    try {
        $result = Resolve-DnsName -Name $dns_name -ErrorAction Stop
        $result | Format-Table Name, IPAddress
    } catch {
        Write-Host "Unable to resolve $dns_name. Error: $($_.Exception.Message)" -ForegroundColor Red
    }
}

# Function to view network adapter information
function View-NetworkAdapters {
    Write-Host "`nNetwork Adapter Information:" -ForegroundColor Yellow
    Get-NetAdapter | Where-Object Status -eq "Up" | Format-Table Name, InterfaceDescription, Status, LinkSpeed
}

# Function to perform traceroute
function Perform-Traceroute {
    $destination = Read-Host "Enter the destination for traceroute"
    Write-Host "`nPerforming traceroute to $destination..." -ForegroundColor Yellow
    Test-NetConnection -ComputerName $destination -TraceRoute | 
        Select-Object -ExpandProperty TraceRoute | 
        ForEach-Object { Write-Host $_ }
}

# Function to view open ports
function View-OpenPorts {
    Write-Host "`nViewing open ports..." -ForegroundColor Yellow
    Get-NetTCPConnection | Where-Object State -eq "Established" | 
        Format-Table LocalAddress, LocalPort, RemoteAddress, RemotePort, State
}

# Function to check internet connectivity
function Check-InternetConnectivity {
    Write-Host "`nChecking internet connectivity..." -ForegroundColor Yellow
    $testResult = Test-NetConnection -ComputerName "www.google.com" -InformationLevel "Detailed"
    if ($testResult.TcpTestSucceeded) {
        Write-Host "Internet is accessible." -ForegroundColor Green
    } else {
        Write-Host "Internet is not accessible." -ForegroundColor Red
    }
    $testResult | Format-List
}

# Function to view IP configuration
function View-IPConfiguration {
    Write-Host "`nIP Configuration:" -ForegroundColor Yellow
    Get-NetIPConfiguration | Format-List InterfaceAlias, IPv4Address, IPv6Address, DNSServer
}

# Function to perform a network speed test
function Perform-SpeedTest {
    Write-Host "`nPerforming network speed test..." -ForegroundColor Yellow
    # Note: This requires the installation of speedtest-cli
    # You can install it using: winget install Ookla.Speedtest.CLI
    try {
        $result = speedtest --format=json --progress=no | ConvertFrom-Json
        Write-Host "Download Speed: $([math]::Round($result.download.bandwidth / 125000, 2)) Mbps"
        Write-Host "Upload Speed: $([math]::Round($result.upload.bandwidth / 125000, 2)) Mbps"
        Write-Host "Ping: $($result.ping.latency) ms"
    } catch {
        Write-Host "Unable to perform speed test. Make sure speedtest-cli is installed." -ForegroundColor Red
    }
}

# Function to flush DNS cache
function Flush-DNSCache {
    Write-Host "`nFlushing DNS cache..." -ForegroundColor Yellow
    Clear-DnsClientCache
    Write-Host "DNS cache flushed successfully." -ForegroundColor Green
}

# Function to view routing table
function View-RoutingTable {
    Write-Host "`nRouting Table:" -ForegroundColor Yellow
    Get-NetRoute | Format-Table DestinationPrefix, NextHop, RouteMetric, ifIndex
}

# Main program loop
do {
    Show-Menu
    $choice = Read-Host "`nEnter your choice (1-11)"

    switch ($choice) {
        "1"  { Ping-Host }
        "2"  { Resolve-DNSName }
        "3"  { View-NetworkAdapters }
        "4"  { Perform-Traceroute }
        "5"  { View-OpenPorts }
        "6"  { Check-InternetConnectivity }
        "7"  { View-IPConfiguration }
        "8"  { Perform-SpeedTest }
        "9"  { Flush-DNSCache }
        "10" { View-RoutingTable }
        "11" { Write-Host "Exiting program..." -ForegroundColor Yellow; break }
        default { Write-Host "Invalid choice. Please try again." -ForegroundColor Red }
    }

    if ($choice -ne "11") {
        Read-Host "`nPress Enter to continue..."
    }
} while ($choice -ne "11")

This advanced Network Diagnostics Tool includes:

1. A comprehensive menu with 11 options
2. Functions for various network diagnostic tasks:
   • Pinging a host
   • Resolving DNS names
   • Viewing network adapter information
   • Performing a traceroute
   • Viewing open ports
   • Checking internet connectivity
   • Viewing IP configuration
   • Performing a network speed test (requires speedtest-cli)
   • Flushing DNS cache
   • Viewing the routing table
3. Use of various PowerShell cmdlets related to networking
4. Error handling for network operations
5. Formatting of output for better readability

This script provides a more comprehensive set of tools for network diagnostics and troubleshooting. It’s suitable for users who want to perform a wider range of network-related tasks and gain more detailed insights into their network configuration and performance.

Note: The speed test function requires the installation of speedtest-cli, which can be installed using the Windows Package Manager (winget) or downloaded from the Ookla website.