IPv6 Address Plan Audit — TechKnowSurge

About this interactive

An IPv6 address plan for a company starts from the public prefix its ISP assigns, usually a /48. There is no private range to choose and no NAT: every host on every LAN gets a public address from its LAN's /64. The work is in the 16-bit subnet ID, the fourth hextet, and the usual way to lay it out is by nibbles: one hex digit for the region, one for the site, two for the department, with region 0 kept for the links between regions. Each field is counted in hex, in its own place, so in 2001:db8:91::/48 the network 2001:db8:91:2a0c::/64 is region 2, site 10, department 12. This audit gives you a draft plan to check line by line: the allocation, the layout, the networks and the notes. Some lines are wrong; find each one. Lines that look odd may still be right, so work every value out. After you submit, every wrong line is shown with what is wrong and the fix.

What you'll learn

Check a corporate IPv6 address plan built from a public /48: public addressing for every host, a /64 for every LAN, and regions, sites and departments laid out by nibble
Find and fix the faults in such a plan: a block's prefix length, a field written in decimal or out of order, a nibble count or capacity that is off

Aligned to

Cisco CCNA

1.8 Configure and verify IPv6 addressing and prefix

1.9 Describe IPv6 address types

Cisco CCST Networking

2.3 Identify IPv6 addresses and prefix formats

CompTIA Network+

3.4 Given a scenario, implement IPv4 and IPv6 network services

Key terms

Hierarchical Subnetting: A structured approach to dividing an IP address space into levels such as regions and sites to reflect an organization's topology.
Nibble Boundary: A subnetting division point aligned to a 4-bit (one hexadecimal digit) boundary in an IPv6 address, simplifying hierarchical address allocation.
Global Unicast Address: A publicly routable IPv6 unicast address beginning with the prefix 2000::/3, equivalent in role to a public IPv4 address, used to identify a device uniquely across the internet. GUAs are assigned by ISPs and regional internet registries and are the addresses used for internet-facing communication in IPv6.
Network Address Translation: A method that maps private IP addresses to a public IP address, allowing multiple devices to share a single public IP.

Topics

Ipv6 Address Planning Hierarchical Subnetting Nibble Boundary Interactive Spot The Error

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