Copyright Goodheart-Willcox Co., Inc. Chapter 8 Overview of Network Security and Network Threats 261 with them. Essentially, in IPv4, APIPA addresses are rendered useless. A link-local address begins with either FE80, FE90, FEA0, FEB0. All devices, including printers, servers, and computers, obtain a link-local address automatically. They will all be using the same local network if they need to communicate. A link-local address may contain a percent sign (%) followed by numbers. This occurs if the system has multiple network adapters. The number after the percent sign represents a zone IP. This is done to differentiate the different link- local addresses from each other. A site-local address is similar to a private address in IPv4, such as 10, 172.16 through 172.31, or 192.168. Since there are so many global unicast addresses avail- able, you may not even use this address type. A site-local address begins with FEC0. IPv6 also has a special address that designates the local host (the one you are working on). This address is 0000:0000:0000:0000:0000:0000:0000:0001, or ::1. This is the “home” address for IPv6, just as 127.0.0.1 is the “home” address for IPv4. Quick Look 8.1.3 IPv6 Address Exploration The IPv6 protocol offers many more addresses than the IPv4 protocol. Recall that IPv6 addresses are formatted differently from IPv4 addresses. 1. Launch a web browser, and navigate to the IANA’s website (www.iana.org). 2. Click the Number Resources link on the home page. 3. Scroll down to the IP Address Allocations area of the page, and click the IPv6 Address Space link. This shows the allocation of all IPv6 addresses, regardless of type. The forward slash (/) and a number referenced here represents the number of bits in the global routing prefi x called the Top Level Aggregator ID (TLA ID). 4. What is FC00::/7 quartet used for? 5. On a Windows computer, open Control Panel, and click the Network and Sharing Center link. 6. Click the Change adapter settings link on the left of the new screen. 7. Right-click on the primary network adapter, and click Properties in the shortcut menu. In the Properties dialog box, ensure the Internet Protocol Version 6 (TCP/IPv6) check box is checked, as shown. Checked