Manage Host Sharing and Personal Firewall

Question 1

Which sharing services can macOS Mojave provide?

Answer 1

The macOS Mojave Sharing Services include the following:
• Remote Disk (DVD or CD sharing)
• Screen Sharing
• File Sharing
• Printer (and scanner) Sharing
• Remote Login
• Remote Management (ARD)
• Remote Apple Events
• Internet Sharing
• Bluetooth Sharing
• Content Caching

Question 2

What is content caching?

Answer 2

Content caching helps reduce Internet bandwidth usage and speed up software installation and iCloud
content sharing on Mac computers, iOS devices, and AppleTV devices.

Question 3

Which app can provide on-demand screen sharing even when the Screen Sharing service isn’t
enabled?

Answer 3

Messages provides on-demand screen sharing that you can use when the system screen-sharing
service isn’t enabled.

Question 4

Which network service or services does Screen Sharing need in macOS Mojave?

Answer 4

In macOS Mojave, Messages screen sharing uses iMessage. Users on both Mac computers must sign in
to iCloud.

Question 5

What’s AirDrop, and how do you know if a specific Mac supports it?

Answer 5

AirDrop provides a quick and easy way to share files within local Wi-Fi and Bluetooth range. AirDrop
creates a secure peer-to-peer network between local devices. From the Finder Go menu, you can verify
that a Mac supports AirDrop.

Question 6

If other devices with AirDrop enabled don’t appear in the AirDrop browser, which two settings on a Mac
can you change to potentially make more devices appear?

Answer 6

On a late-model Mac, you’ll find two settings at the bottom of the AirDrop browser that control AirDrop
discovery. The first setting expands AirDrop discovery from only users in your Contacts to everyone
within AirDrop range. The second setting makes AirDrop revert to the previous discovery method,
which allows your Mac to discover older Mac computers and Mac computers that run previous versions
of Mac operating systems.

Question 7

In what primary way does the macOS built-in firewall differ from a traditional network firewall?

Answer 7

With the firewall built into macOS Mojave, connections are allowed or denied on a per-app basis. This is
unlike traditional network firewalls, where access rules are based on network service port numbers.

Question 8

In macOS Mojave, what are the firewall settings?

Answer 8

In macOS Mojave, the firewall settings are as follows:
• Block all incoming connections.
• Automatically allow built-in software to receive incoming connections.
• Automatically allow downloaded signed software to receive incoming connections.
• Enable stealth mode.

Question 9

How does enabling stealth mode affect the way your Mac communicates with other hosts? How does
blocking all incoming connections affect it?

Answer 9

When stealth mode is enabled, your Mac doesn’t respond to unauthorized network connections,
including network diagnostic protocols like ping, traceroute, and port scan. Your Mac still responds to
other allowed services. This includes Bonjour, which announces your Mac computer’s presence and
prevents your Mac from being hidden on the network. When you block all incoming connections, your
Mac won’t respond to incoming network connections except for those required for basic network
services or established connections, such as those needed to browse the web or check email. This
prevents shared services or apps hosted on your Mac from working remotely.