Home > Articles > Cisco Certification > CCNA Routing and Switching > IPv6 According to ICND1 Version 2

IPv6 According to ICND1 Version 2

  • Article is provided courtesy of Cisco Press.
  • Date: Mar 26, 2013.

Article Description

Anthony Sequeira examines many of the key facts that one should know about the next generation of the Internet Protocol suite, IPv6, at the modified CCENT level. This article also serves as a guide for understanding the scope of what is covered in the new ICND1.

Like this article? We recommend

CCENT/CCNA ICND1 100-101 Official Cert Guide

CCENT/CCNA ICND1 100-101 Official Cert Guide

$39.99

For more information on the new Cisco CCENT/CCNA exams, including special offers and study guides, visit our Cisco Press "About CCNA" page.

One of the most exciting things for me personally about the new ICND1 course from Cisco Systems is the fact that it delves even deeper into the next generation of the Internet Protocol suite. This next generation is known as IPv6.

In this article, we will examine many of the key facts that one should know about this protocol suite at the modified CCENT level. While this article might teach you some very specific facts, it will also serve as a nice guide for you to understand the scope of what is covered in the new ICND1.

We will not try to cover every detail, but at least by the end, you might have learned a thing or two and you will have a nice sense of what to study harder. Determining the scope of what to study with a topic like IPv6 is very important because you could fill an entire course or two just by studying IPv6 alone!

Introducing Basic IPv6

Most people realize that the main impetus for IPv6 is the fact that we are running out of available TCP/IP version 4 addresses. Network Address Translation (NAT) has been the main Band-Aid for this problem, and it certainly has done a remarkable job in holding off complete and total address depletion. But while many realize this about addressing, they do not realize how many more incredible features are gained in the new protocol suite.

IPv6 is simplified and made more efficient, more secure, and more mobile. We could very easily fill a brochure trying to sell someone on the new protocol suite.

But, alas, the new address space does get all the press. And it turns out that this is the main area of what you are expected to know about at the CCENT (ICND1) level. An IPv6 address is now 128 bits long (this is up from just 32 bits in IPv4). the remarkable increase in the number of addresses this expansion creates has been widely publicized. You can break it down to report that it creates billions and billions of available addresses for every little piece of the Earth’s surface. When you have an address that long, dotted decimal will no longer work well for the representation, so IPv6 addresses are represented with eight 16-bit hexadecimal fields that are separated by colons. 

Here is an example of an IPv6 address:

2001:0DB8:010F:0001:0000:0000:0000:0ACD

There are three rules you absolutely need to remember:

  • The A, B, C, D, E, and F in the hex fields are case-insensitive.
  • The leading zeros in the fields are optional.
  • Once in an address, you can represent successive fields of all zeros with a ::.

So for example, our address example can be represented just fine as follows:

2001:d88:10f:1::acd

That sure is a bit easier to deal with!

If you heard that there are no more broadcast packets in IPv6—you heard right. Multicast (addressing a packet for a group) completely replaces broadcasting. If you need to send a packet to every machine on the local segment, you can send the packet to the all nodes multicast address.

Unicasting packets still exists, of course, and you can also have anycast addressing. When you anycast, you configure the same unicast address on all members of a group. Now local routers can choose a device in the anycast group they deem "closest." As an administrator, you can program the routers to dictate how they deal with this definition of "closest." 

A very important type of unicast address that's created automatically in IPv6 is called the link-local address. This address allows two IPv6 systems to immediately communicate with each other, but only over the local link. A link-local address is easy to spot because it always begins with FE80. Remember, the link-local address is created automatically any time you enable IPv6 on an interface (the ipv6 enable command) or if you assign a regular unicast address to the interface.

In IPv6 addressing, nodes can configure their own 64-bit host portion of their IPv6 address. The first 64 bits of the address are recommended for the network portion of the address. The format for a node automatically calculating its own host address portion is known as EUI-64. The MAC address on the device is used to create a unique 64-host ID.

Configuring an IPv6 address on a router interface is simple. In fact, in many places on a Cisco router or switch, the correct IPv6 command just replaces the keyword ip with ipv6. Setting an address is an example of this:

BellaRouter(config-if)# ipv6 address 2001:db8:D1A5:C900::/64 eui-64

Other Exciting Features

Other great features of IPv6 include these:

  • A simplified and standard size IPv6 header in packets.
  • Improved ICMPv6 that takes on more roles and responsibilities.
  • Automatic Neighbor Discovery process.
  • Stateless autoconfiguration: The local router gives the device its network prefix, and the device automatically creates its host portion using the EUI-64 format, as described earlier in this article. The ipv6 address autoconfig command is all that is required on a Cisco device to instruct the device to automatically acquire its address information.
  • Stateless DHCP: Since devices can configure their own addresses now (with the help of routers), there is no longer a need for DHCP to assign and track IPv6 addresses. Instead, a DHCP server can be used to assign additional information such as DNS server and default gateway addresses; this is known as stateless DHCP.

Configuring IPv6 Static Routing and OSPFv3

In order to enable the capability of your Cisco router to actually route static and dynamic protocols like OSPF, use the following command:

BellaRouter(config)# ipv6  unicast-routing 

In order to configure a static route, once again just replace the ip keyword command from the previous version of the command:

BellaRouter(config)# ipv6 route 2001:DB8:A01::/48 Gi0/1  2001:DB8:D1A5:C900::1

For an OPSFv3 configuration, enable OSPF under the interfaces that you want to run the routing protocol over and make sure to assign a 32-bit router ID, which is required if your router does not possess any 32-bit IPv4 addresses that the router can choose automatically:

BellaRouter(config)# interface GigabitEthernet0/0 
BellaRouter (config-if)# ipv6 ospf 1 area 0 
BellaRouter (config-if)# exit
BellaRouter (config)# interface GigabitEthernet0/1 
BellaRouter (config-if)# ipv6 ospf 1 area 0 
BellaRouter (config-if)# exit
BellaRouter (config)# ipv6 router ospf 1 
BellaRouter (config-rtr)# router-id 0.0.0.1

You verify IPv6 configurations just as you would in IPv4. For example, the following commands could be used for verifications of the above configurations:

  • show ipv6 route: View the IPv6 routing table on the device.
  • show ipv6 interface brief: View a quick summary of the router interfaces, their IPv6 addresses, and their Layer 1 and Layer 2 status.
  • show ipv6 ospf neighbor: View a table of OSPF neighbors.
  • show ipv6 protocols: View key information about IPv6 routing protocols configured on the device.

I certainly hope you enjoyed this article and perhaps learned a thing or two. At the very least, perhaps it piqued your interest to delve into IPv6 and learn even more. Thank you so much for reading.

Cisco Press Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Cisco Press and its family of brands. I can unsubscribe at any time.

Overview

Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Cisco Press products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@ciscopress.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security

Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children

This site is not directed to children under the age of 13.

Marketing

Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out

Users can always make an informed choice as to whether they should proceed with certain services offered by Cisco Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.ciscopress.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links

This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020