Teach Yourself VISUALLY MacBook Pro, 2nd Edition (2014)
Part II. Getting Connected
A MacBook Pro really shines when it is connected to the Internet. As you move around, you need to know how to keep connected without risking the computer or its data. You will also want to connect devices to your MacBook Pro. In this part, you learn how to get and keep your MacBook Pro connected.
Chapter 7. Connecting to a Network and the Internet
Understanding Networking Concepts
Networking is vital to getting the most out of your MacBook Pro. OS X manages most of the details of networking your MacBook Pro for you, but it is helpful to understand essential networking concepts as you create your own network.
Network
Simply put, a network is two or more devices connected together. A network enables the devices on it to communicate with each other. Devices communicate using various protocols to provide different services. For example, the Transmission Control Protocol/Internet Protocol, or TCP/IP, is the basic “language” that devices speak over the Internet. There are other protocols for a variety of services, but the data for all of these services is communicated over a network. Networks can be large or small, simple or complicated, but they all have the same basic purpose.
Internet
The Internet is the largest existing network because it literally spans the globe, and billions of devices and people are connected to it. The Internet makes communication and information available way beyond anything that was possible before it came to be. For example, you can use the Internet for e-mail, searching the web, chatting online, and transferring files. Connecting your MacBook Pro to the Internet is just about as important as being able to charge its battery.
Local Network
A local network, also known as a local area network or LAN, is a network that covers a defined physical space. LANs can be quite large, such as a LAN in a business or school, or fairly small, such as a LAN in a home. A LAN connects devices so they can communicate with one another and also connect to outside networks — most important, to the Internet. This chapter focuses on helping you create a small LAN, such as the ones many people use in their homes. The principles of larger LANs are the same, but the details can get much more complicated.
Ethernet
Ethernet is both a physical means of connecting devices — for example, an Ethernet cable — and the protocol used to communicate over the physical connection. Ethernet can support various communication speeds, including Fast Ethernet at 100 megabits per second (Mbps) and Gigabit Ethernet at 1 gigabit per second (Gbps). You can use a Thunderbolt-to–Gigabit Ethernet adapter or a USB-to-Ethernet adapter to connect your MacBook Pro to an Ethernet network. In addition to their speed, Ethernet connections offer other benefits, including simplicity and security. The primary downside to Ethernet is that it requires cables to make the physical connection between the devices.
Wi-Fi Network
Wi-Fi is a general term for a set of wireless communication standards and technologies defined in the Institute of Electrical and Electronics Engineers (IEEE) 802.11 specifications. Like Ethernet networks, Wi-Fi enables devices to communicate, but it uses radio transmissions instead of physical wires to connect devices. This offers ease of configuration and makes it possible to move around while remaining on a network. The downsides of Wi-Fi are that it is neither as secure nor as fast as Ethernet networks and is prone to interference from other devices operating in the same band.
AirPort
Apple uses the term AirPort for its implementation of Wi-Fi in its wireless base stations, which include AirPort Express, AirPort Extreme, and AirPort Time Capsule. The application used to configure one of these devices is called AirPort Utility. In earlier versions of OS X, the wireless networking capability of Macs was called AirPort too, but in OS X 10.7, or Lion, Apple changed the name to Wi-Fi. AirPort is fully compatible with standard Wi-Fi technologies, such as those used for Windows PCs and networking equipment.
Understanding Networking Concepts (continued)
Switch/Hub/Router/Access Point
All networks need a device that controls the flow of information among the various computers, printers, and other resources on the network. These devices are called switches, hubs, routers, or access points. They can support Ethernet, Wi-Fi, or both kinds of networks. This chapter focuses on the AirPort base stations from Apple, because they offer powerful features and integrate closely with OS X. However, because your MacBook Pro supports standard Wi-Fi technology, you can use it with other kinds of devices as well. Some of the key features of routers are the capability to share an Internet connection among many devices and to shield those devices from Internet attacks.
Internet Service Provider
To connect to the Internet, you need the services of an Internet Service Provider, or ISP for short. The ISP provides the means that you use to connect your network to the Internet using various connection technologies, such as cable; Digital Subscriber Line, commonly referred to as DSL; or even satellite.
Internet Account
To access the Internet, you need an Internet account with an ISP. If you access the Internet through a business or school, that organization acts as your ISP. The cost and technical details, such as the connection speed and the amount of server space you get, vary depending on the specific ISP you use. Typically, an ISP requires you to have only one Internet account for your network. All your computers and devices can connect through your account using your network. You are responsible for maintaining your network and the Internet router, whereas the ISP is responsible for ensuring that the connection from your router to the ISP's equipment is working. Depending on the type of Internet access you use, you might need a username and password to connect to your account, or it might be based on your physical location, as with a cable connection.
IP Address
Each device that connects to the Internet must have an Internet Protocol address, or IP address, that identifies it. An IP address consists of a set of four numbers with periods between each number, as in 169.155.12.3. In most networks, you do not need to worry about the details of IP addresses because the router uses Dynamic Host Control Protocol, DHCP, to automatically assign addresses to devices as needed. You just need to be able to recognize whether or not a device has a valid IP address, which is usually pretty clear because when you do not have one, you cannot connect to the Internet.
Internet Services and Applications
The reason to connect devices to the Internet is to access the services delivered over it. To access these services, you use Internet applications, such as the Mail application for sending and receiving e-mail and the Safari application for browsing the web. Many kinds of services are available on the Internet, and many different applications use each of those services, but you will likely end up using just a few of them. Because OS X includes powerful and easy-to-use Internet applications, they are a good place to start.
Internet Dangers
Although the Internet offers amazing capabilities, it also holds risks and threats. The dangers of Internet life include the annoying, such as pornography and spam, and the truly dangerous, such as viruses, hacking, or identity theft. Fortunately, with some basic precautions and common sense, you can protect yourself from most Internet dangers relatively easily.
Local Network Services
Similar to the Internet, you can take advantage of services that you can provide over your local network. These include file and printer sharing, screen sharing, and messaging. Configuring and using local network services is pretty straightforward because these services are built into OS X.
Obtain an Internet Account
To connect your network or MacBook Pro to the Internet, you must have an Internet account. The most common high-speed technologies for homes are cable and DSL. Satellite and cellular connections are also available. Some communities provide free wireless networks that you can use. Before you decide on an Internet account, research the options available where you live, including the monthly cost, installation costs or startup fees, and length of contract of each option. Verify that potential providers support Macs.
Obtain an Internet Account
Determine Your Options
If cable service is available to you, contact the cable provider to get information about Internet access.
If you have access to a computer connected to the web, go to dsl.theispguide.com.
Use the tools to search for DSL access in your location.
Contact DSL providers that serve your area to get details about their service, including the monthly cost. Have potential providers check your actual phone number to ensure that DSL is available.
Note: If cable or DSL is available to you, skip to step 1 in the next section. Satellite is the best option only when cable or DSL is not available.
If cable or DSL is not available, access the web and move to www.dbsinstall.com.
Follow the links on the DSL provider's website to search for satellite providers of Internet access.
Choose, Obtain, and Install an Internet Account
Compare your options.
If you have only one option for a broadband connection, the choice is made for you, and you can skip to step 3.
If you have a choice between cable and DSL, consider which is best for you based on cost, the provider's reputation for service, and other factors.
Contact the provider you want to use to obtain an account and schedule installation.
The provider activates your account, and if you choose to have the provider install the router, they schedule an appointment with you. Some providers provide a self-install kit for you to set up.
TIPS
What about dialup Internet accounts?
Internet accounts that you access over a standard phone line and dialup modem are available just about everywhere, though you need to add a USB modem to be able to use one with your MacBook Pro. Dialup is very slow and unreliable, and you must connect each time you want Internet access.
If I need an Internet account to connect, why can I use Wi-Fi at public places without an account?
In public places, the organization that controls that place can make a wireless network available to you. Through that network, you can access the organization's Internet account. In some cases, you can do this for free. In others, you need to purchase access from the organization providing the network.
Set Up a Local Network
After you have a working Internet connection, you are ready to build a local network. You can include both wired and wireless devices on the network. The heart of any network is the switch or router you use. The best router choice for most Mac users is an AirPort Extreme or an AirPort Time Capsule because OS X has built-in support for administering the AirPort networks they provide. Also, these base stations shield your network from Internet attacks. The rest of this chapter assumes you are using one of these devices and that you have a working Internet connection and router.
Set Up a Local Network
Install an AirPort Extreme or Time Capsule
Connect the output cable of the router to the WAN (wide area network) port on the AirPort.
Connect power to the AirPort.
Note: An AirPort Time Capsule is an AirPort Extreme that includes a hard drive. This chapter refers to all three types of AirPort — AirPort Extreme, AirPort Express, and AirPort Time Capsule — as “AirPort” for simplicity.
Log in to your MacBook Pro.
As long as you have not disabled Wi-Fi, the MacBook Pro can communicate with the AirPort wirelessly. You can also connect the MacBook Pro directly to one of the Ethernet ports on the AirPort using an Ethernet cable and adapter.
Configure an AirPort
Note: The specific screens and options you see in AirPort Utility depend on the type of AirPort you are configuring and its current status. These steps show a new AirPort Time Capsule.
Click Wi-Fi (
) on the menu bar.
Click the new AirPort.
The AirPort Utility application opens and connects to the AirPort.
In the Network Name box, either accept the default name or type the name you want to use for the network.
In the Base Station Name box, either accept the default name or type the name you want to give the AirPort.
Deselect the Use a single password check box (
changes to 
) if you want to use separate passwords for accessing the network and the AirPort. Otherwise, leave this check box selected () to use a single password for both.
Enter the password for the wireless network you are creating in the Password box.
Type the password again in the Verify box.
Click Next.
AirPort Utility prompts you to create a guest Wi-Fi network.
Note: A guest network connects to the Internet but not to the computers and devices on your network. You would use a guest network to give your guests Internet access.
If you want to create a guest network, select the Enable guest network check box ( changes to ) and type a name for it in the box.
Click Next.
AirPort Utility announces the new network is available.
Click Done.
The Wi-Fi network is ready to use.
TIPS
What do the lights next to devices in AirPort Utility mean?
The status light next to each device shows you how the device is functioning. A green light means everything is working correctly. A flashing orange light indicates a problem. No light indicates the device is currently not communicating.
What does the Other Options button do?
By default, a new AirPort is set up to provide a wireless network. If you click the Other Options button, you can choose to add the device to another network or to replace an existing device. In most cases, the default choice is what you want to use for a new network.
Set Up a Local Network (continued)
You can use AirPort Utility to manually configure an AirPort. This is useful when you want to change something about how the AirPort works, such as the name or password of the wireless network. You can configure many different options using AirPort Utility. Some of these options are mostly useful for larger networks; for a home network or other small network, you usually need to set only a few options. This section shows you how to run AirPort Utility and change some of the more useful options.
Set Up a Local Network (continued)
Use AirPort Utility to Configure an AirPort
Click Launchpad (
) on the Dock.
Type a.
Launchpad displays only the items that include a word starting with a.
Click AirPort Utility (
).
The AirPort Utility application opens and shows you the devices with which it can communicate.
Click the device you want to configure.
The Details pane opens.
A If the Update button appears, you can click it to update the AirPort's firmware to the latest version. Updating is usually a good idea, because updates can eliminate bugs or add features.
Click Edit.
Note: The administrative password is the password you must enter before you can change the AirPort's configuration. It is a good idea to use a different base station password from the password for connecting to the network the AirPort provides.
Click the Base Station tab.
If necessary, change the AirPort's name by typing a new name in the Base Station Name box.
To set an administrative password for the AirPort, enter it in the Base Station Password box.
Type the password again in the Verify box.
Select the Remember this password in my keychain check box ( changes to ).
Click the Wireless tab.
If necessary, type a new name for the wireless network the AirPort provides.
Click the Wireless Security pop-up menu (
) and select the security type to use.
Note: WPA2 Personal is normally the best security type for a home network.
Type the password for the wireless network.
Type the password again in the Verify box.
Select the Remember this password in my keychain check box ( changes to ).
Select the Enable Guest Network check box ( changes to ) if you want to create a guest network.
Type the name for the guest network.
Click the Guest Network Security pop-up menu () and select the security type.
Note: Choose None if you want your guest network to be open to anyone within wireless range.
Enter the password for the guest network if you chose to use security.
Click Update.
AirPort Utility applies the changes to the AirPort and restarts it.
TIP
What is the difference between an AirPort Extreme and an AirPort Express?
The AirPort Express is designed mostly for home use and can play streaming audio through speakers you connect to it. The AirPort Extreme is designed for both home use and business use and cannot play streaming audio.
Protect Your MacBook Pro from Internet Attacks
The Internet connects you to an unlimited number of people and organizations. This opens you up to Internet attacks ranging from attempts to steal your data or identity to suborning your computer to launch attacks on other computers. You also need to be mindful of the threat from viruses. Fortunately, you can protect yourself with relatively simple steps. An AirPort Extreme or AirPort Time Capsule protects you from most attacks automatically. If you ever connect your MacBook Pro directly to your router, such as for troubleshooting, make sure you turn on its firewall before doing so.
Protect Your MacBook Pro from Internet Attacks
Enable NAT on Your AirPort
Click Launchpad () on the Dock.
Click AirPort Utility.
Click the AirPort you want to configure.
Click Edit.
Click the Network tab.
Click the Router Mode pop-up menu () and select DHCP and NAT.
Click Update.
AirPort Utility applies the changes to the AirPort and restarts it.
Note: When NAT is active, the only IP address exposed to the Internet is the AirPort's. This shields the devices connected to the Internet through the AirPort from Internet attacks because devices outside your AirPort cannot identify the devices on the network; they see only the AirPort, which cannot be hacked like a computer can.
Enable the OS X Firewall
Open the System Preferences application and click Security & Privacy.
Click Firewall.
Click Turn On Firewall.
Note: You must authenticate yourself to configure the firewall.
The firewall starts up and protects your MacBook Pro.
Note: Chapter 9 explains performing more advanced configuration of the firewall.
Protect Your MacBook Pro from Viruses
Get and install an antivirus application.
Note: Most OS X antivirus software is commercial, but you can download a free virus scanner called ClamXav 2 from http://clamxav.com.
Configure the antivirus application so that it updates its virus definitions and scans your MacBook Pro automatically (see the instructions for the particular application you use).
TIP
What other options are there for a wireless network?
If you click the Wireless Options button on the Wireless tab, you can set up a network on the 5GHz channel, which can sometimes help you avoid interference with nearby wireless networks. 5GHz requires your computer or device to have 802.11n or 802.11ac capability; if it cannot see the network, it lacks such capability. You can also manually change the channel of both the regular 2.4GHz channel and the 5GHz channel to avoid interference. You can also hide the network by preventing it from broadcasting its name.
Connect to the Internet with Wi-Fi
With a Wi-Fi connection, you can use the Internet from wherever you are — on the couch at home, in the yard, or anywhere your cellular phone or cellular modem can connect to the cellular network. You use the same steps to connect to a Wi-Fi network outside your LAN, to a Personal Hotspot network or Portable Hotspot network on your cellular phone, or to your cellular modem.
Connect to the Internet with Wi-Fi
Connect to a Wi-Fi Network
Open the System Preferences application.
Click Network.
A The left pane shows the available network interfaces.
Click Wi-Fi.
B The Wi-Fi controls appear in the right pane.
Click Turn Wi-Fi On if it is not on already.
Click the Network Name pop-up menu ().
Click the network you want to join.
Type the password.
C You can select the Show password check box ( changes to ) to display the password's characters. This can be helpful with complex passwords.
Select the Remember this network check box ( changes to ) if you will use this network again.
Click Join.
The MacBook Pro connects to the Wi-Fi network, and you return to the System Preferences application window. The status of the network becomes Connected.
Select the Show Wi-Fi status in menu bar check box ( changes to ) to make the Wi-Fi menu appear on the menu bar.
Click Apply if this button is enabled.
Click Close (
).
Open Safari and go to a web page.
The web page opens, showing that the MacBook Pro is connected to the network and the Internet through Wi-Fi.
If the web page does not open, troubleshoot the problem.
Note: See the section “Troubleshoot an Internet Connection” for information on how to troubleshoot connection problems.
Use the Wi-Fi Menu
Click Wi-Fi ().
The Wi-Fi menu opens.
D The number of waves on the Wi-Fi menu shows the signal strength. More waves mean a stronger connection.
Click the network you want to join.
TIP
How can I connect directly to another Mac using Wi-Fi?
Click Wi-Fi () on the menu bar and select Create Network. Name the network, and then click the Security pop-up menu () and select 128-bit WEP. Type a 13-character password and click OK. Other Mac users can connect to your network using the same steps they use to connect to a network provided by an AirPort.
Connect to the Internet with Ethernet
Using a Thunderbolt-to–Gigabit Ethernet adapter or a USB-to-Ethernet adapter, you can connect your MacBook Pro to a wired network that shares an Internet connection. This gives your MacBook Pro access to the Internet through the wired network. You may need to choose settings in the Network pane in System Preferences to make the connection work. This section assumes you are using an AirPort. If you have a different network configuration, the details might be slightly different.
Connect to the Internet with Ethernet
Connect the MacBook Pro to an Ethernet Network
Connect an Ethernet cable to one of the available ports on the AirPort.
Connect the other end to the Ethernet port on the Thunderbolt-to–Gigabit Ethernet adapter or USB-to-Ethernet adapter.
Connect the adapter to your MacBook Pro.
Configure the MacBook Pro to Access the Internet over an Ethernet Network
Open System Preferences.
Click Network.
A The Network pane appears.
Click Ethernet in the left pane.
B The status should be Connected. If it is not, the cable is not connected correctly or the AirPort is not working.
Click the Configure IPv4 menu () and select Using DHCP.
Click Apply if this button is enabled.
Click Close ().
The System Preferences application closes.
Click Safari (
) on the Dock.
Safari opens.
If Safari does not load a web page automatically, type a URL in the address bar and press 
.
C Safari displays the website when the MacBook Pro has successfully connected to the network via Ethernet. If it does not, troubleshoot the problem.
Note: See the section “Troubleshoot an Internet Connection” for information on troubleshooting connection problems.
Note: For detailed information about using Safari, see Chapter 11.
TIPS
Why use Ethernet when wireless is available?
Wireless connections are great because you are not tethered to one spot. But Ethernet connections typically provide better performance than wireless connections and do not suffer interference issues. Additionally, an Ethernet connection is more secure because a device has to be physically connected to the network to use it.
Can I have more than one connection active at a time?
A MacBook Pro can have multiple connections to networks active at the same time. You can use the steps in this section to configure your MacBook Pro for Ethernet access and the steps in the previous section to configure it for wireless access. OS X chooses the connection to use at any point in time based on how you configure it and the connections available.
Using AirDrop to Share Files
The AirDrop feature enables you to share files easily and instantly with nearby Macs. AirDrop automatically locates other AirDrop-capable Macs running OS X Lion or later versions that have Wi-Fi on, that are in range of your MacBook Pro, and whose users have their AirDrop folder selected. Your AirDrop folder displays an icon for each Mac using AirDrop; to share files with the person using that Mac, you simply drop the file on that Mac's icon. Likewise, people can share files with you by dropping them on your MacBook Pro's icon on their Macs.
Using AirDrop to Share Files
Use AirDrop to Share Files
Open a Finder window.
Click AirDrop.
Ask the people with whom you want to share a file to select AirDrop on their computers.
A Your AirDrop icon appears at the bottom of the window.
B Each Mac on the same network as your MacBook Pro with an AirDrop window active appears above your icon. The Mac's name appears, bearing the image for the active user account.
Drag the file you want to share onto another user's icon. You can drag it either from the desktop or from another Finder window.
Note: You can share multiple files at the same time by selecting them and dragging them to the other user's icon.
A confirmation dialog opens.
Click Send.
If the person accepts the file you sent, you get no feedback. If the person declines the file, you see a message to that effect.
Receive Files via AirDrop
When someone sends you a file via AirDrop, you see a notification showing the source computer's name, the file name, and a preview of its content.
Respond to the notification.
C To save the file in your Downloads folder, click Save.
Note: Never accept a file unless you are absolutely sure about the computer sending the file to you. If you accept files from people you do not know, your Mac and its data could be in jeopardy.
D To save the file in your Downloads folder and open it, click Save and Open.
If you click Save or Save and Open, you see the file's icon “jumping” from the AirDrop folder to the Downloads icon on the Dock.
E To prevent the file from being moved onto your computer, click Decline.
If you accepted the file, you can work with it.
TIPS
Why can I not see other Macs in the AirDrop window when I know they are on the same network?
AirDrop must be selected in at least one Finder window on each computer. If a user closes the AirDrop window, you no longer see her icon in the window. As soon as she selects AirDrop, her icon reappears in your AirDrop window. Each Mac must also have AirDrop-compliant hardware.
How can I keep AirDrop available without using up screen space on a Finder window just for AirDrop?
Open a Finder tab and click AirDrop. Open other tabs in the Finder window to use them to access files and folders. AirDrop is available, even if the tab is hidden by others.
Share Files on a Local Network
Just like services you access over the Internet, you can provide services over a local network. These include sharing files, printers, and an Internet connection; and iTunes sharing and streaming. Any computers that connect to the network, whether they use Ethernet or Wi-Fi, can access any of the services you make available. File sharing is one of the most useful local network services because you can easily share resources among multiple computers. You can configure your MacBook Pro to share files with others, and you can access files being shared with you.
Share Files on a Local Network
Share Files with Others
Open the System Preferences application.
Click Sharing.
A The left pane lists the services you can provide over a local network. When you select a service, the tools you use to configure it appear in the right part of the window.
Type a name for your MacBook Pro in the Computer Name box.
This is the name others on the network choose to access your MacBook Pro.
Note: This is the name AirDrop uses for your MacBook, too.
Select the File Sharing check box ( changes to ).
File sharing starts.
B By default, OS X shares the Public folder for each user account.
To share a specific folder, click Add (
).
Move to and select the folder you want to share.
Click Add.
C The folder you selected appears on the Shared Folders list.
Click the folder in the Shared Folders list.
In the Users list, click the user for whom you want to set access. For example, click Everyone.
Click the Access pop-up menu ().
Click the access level, such as Read & Write.
Note: See the tip in this section for an explanation of access levels.
To configure more users, click Add () at the bottom of the Users list.
The Select Users sheet appears.
Choose the users for whom you want to configure access.
Click Select.
The users appear on the Users list.
Repeat steps 8 to 11 to configure the user's access to the shared folder.
Repeat steps 5 to 14 to share other folders and configure users to access your shared files.
TIP
What are the permissions I can assign to folders that I share?
Assign No Access to prevent people from accessing an item at all. Assign Write Only (Drop Box) to enable people to place items within the shared folder, but not to view or change its contents. Assign Read Only to enable people to view items but not change them. Assign Read & Write to enable people to view items, change their contents, and create new items.
Share Files on a Local Network (continued)
When you connect to a local network, your MacBook Pro automatically identifies resources on the network that are sharing files. It displays these resources in the Shared section of the Sidebar so that you can access them easily. When you connect to a sharing resource, what you can do with the content of that resource is determined by the permissions that you have been granted for it. For example, if you have Read & Write access, you can use a shared folder just like one you created. If you have Read Only access, you can see its contents, but you cannot change those contents.
Share Files on a Local Network (continued)
Access Files Being Shared with You
Open a Finder window.
D The Shared section of the Sidebar shows all the computers sharing files on the network.
Click the computer whose files you want to access.
Click Connect As.
To connect as a guest, select Guest (not shown) and skip to step 9.
Note: By default, the Public folder in each user's Home folder is available to everyone on the network.
To connect as a registered user, select Registered User (
changes to 
).
Type the username of the account under which you want to connect.
Type the password for the username you typed in step 6.
Select the Remember this password in my keychain check box ( changes to ).
Click Connect.
Your MacBook Pro connects to the resource under the user account you entered.
E The Finder window that appears shows the resources available to you based on the kind of access the user account you used has.
F The user account under which you are logged in is shown here.
G At the top of the window, you see the Sharing icon indicating that the resource you are using is stored on a different computer on the network.
Open a shared resource.
Open folders on the shared resource.
Double-click files to open them.
To copy a file or folder from the shared resource to your MacBook Pro, drag it from the shared resource folder onto a folder stored on your MacBook Pro.
TIPS
When are the files that I share available to others?
For people to access files you are sharing, your MacBook Pro must be awake and connected to the network. If a MacBook Pro is configured to go to sleep automatically, people lose access to shared files when it sleeps unless you select the Wake for Wi-Fi Network Access check box ( changes to ) on the Power Adapter pane in Energy Saver preferences. Likewise, if your MacBook Pro is no longer connected to the network, its files are not available.
How can I share files with Windows computers?
Turn on File Sharing by selecting its check box. Click Options. Select the Share files and folders using SMB (Windows) check box ( changes to ). Select the check box next to each user ( changes to ) and type the password for that user's account. The user can access the files by typing smb://ipaddress, where ipaddress is the current IP address of your MacBook Pro; this address appears in the Sharing pane.
Share Screens on a Local Network
With screen sharing, you can control another Mac on your local network just as if you were sitting in front of it. For example, you can share the screen of a different Mac on your network and run an application on that Mac as if it were installed on your MacBook Pro. This is also useful for helping other users on your network because you can take control of the other computer to solve problems. Like file sharing, you must configure screen sharing permissions on each computer to determine who can access this feature.
Share Screens on a Local Network
Configure Screen Sharing on a Mac
On the Mac whose screen you want to share, open System Preferences and click Sharing.
Select the Screen Sharing check box ( changes to ).
Click Computer Settings.
Select the Anyone may request permission to control screen check box ( changes to ) if you want to allow anyone to request to share your screen.
Select the VNC viewers may control screen with password check box ( changes to ) and enter a password if you want people using Virtual Network Computing connections to be able to control your MacBook Pro.
Click OK.
Select All users ( changes to ) to allow anyone who can access your MacBook Pro over the network to share its screen, or select Only these users ( changes to ) to create a list of user accounts that can share your screen.
A To create a user list, click Add (). The User Account sheet appears. Select the user accounts with which you want to share your screen and click Select.
B The readout below Screen Sharing: On shows the VNC address and computer name for your Mac.
Share Another Computer's Screen
Open a Finder window.
Click the Mac whose screen you want to share.
Click Share Screen.
Select As a registered user ( changes to ).
Type your user name for the other Mac.
Type your password for the other Mac.
Select the Remember this password in my keychain check box ( changes to ) if you want to store the password for future use.
Click Connect.
Note: If a Screen Sharing dialog opens offering you the choice between sharing the display and logging in, click Share Display.
C Within the Screen Sharing application's window, which has the other computer's name as its title, you see the other computer's desktop.
Within the Screen Sharing window, you can control the shared Mac.
When you finish using Screen Sharing, click Screen Sharing and then click Quit Screen Sharing to quit the application.
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How can I share another computer's screen if that computer is not on my local network?
You can use the Screen Sharing feature in the Messages application to share screens with your chat contacts or view their screens. If you have an iCloud account, you can use the Back to My Mac feature to access your own Macs across the Internet. On the iCloud pane of the System Preferences application, register your iCloud username and password on each computer among which you want to share screens, and then select the Back To My Mac check box ( changes to ) to enable it.
Troubleshoot an Internet Connection
You can troubleshoot your Internet connection if you have problems with it. If an error message appears, determine if the problem is a network issue or if it is related just to one computer by trying the same action on a different computer on the same network.
Troubleshoot an Internet Connection
Troubleshoot a Network Problem
Check the status lights on the router to make sure it is working.
If the router appears to be working, go to step 2. If not, go to step 7.
Check the status of the AirPort.
If the status lights indicate the base station is working, go to step 3. If not, go to step 7.
Use a thin, blunt object such as the end of a straightened paper clip to press the Reset button on the back of the AirPort.
Try the task that you had a problem with.
If it is successful, you are done; if not, continue with the next steps.
If the router's power light is on but the connection light is not, contact the ISP to make sure service is available. If it is not, you need to wait until service is restored.
When you are sure that your Internet service has been restored, restart the AirPort again.
Try the task that you had a problem with.
The problem should be solved.
Troubleshoot a MacBook Pro Problem
Open System Preferences and click Network.
Check the status of the various connections.
If the status is Not Connected for a connection, you need to reconfigure that connection using the steps outlined in the section “Connect to the Internet with Wi-Fi” or the section “Connect to the Internet with Ethernet.”
If the status is Connected, click the Apple icon (
).
Hold down 
and click Restart.
Note: +clicking Restart makes OS X restart without displaying the confirmation dialog.
After the MacBook Pro restarts, try the activity again.
TIPS
How can I get help diagnosing a problem?
Open the Network pane of the System Preferences application. Click Assist Me. At the prompt, click Diagnostics. Follow the on-screen steps to diagnose the issue. When the application finds a problem, it identifies it and provides some hints about how to solve it. However, using the steps outlined in this section is usually faster because they include most of what the application tells you to do.
What can I do if none of these steps helped?
Visit www.apple.com/support. Search for the problem you are having. Disconnect everything from your network, turn on your computer's firewall, and then connect that computer to the router. If it works, the problem is related to the network; add devices one by one until you find the source of the problem. If the connection does not work, you need help from your ISP.