Showing results for 
Search instead for 
Did you mean: 
Salman Asadullah
Cisco Employee
Cisco Employee




Read the bioSalman Asadulah (CCIE# 2240) is a Cisco Distinguished Engineer and also serves as IPv6 Forum Fellow, Broadband Forum Ambassador, and Co-chair of the IPv6 Education Certification Program. He has been working with large-scale IP and multiservice network and technologies for more than 15 years. He is a coauthor and contributor to IETF RFCs/IDs and has written three Internetworking books: Cisco CCIE Fundamentals: Network Design & Case Study, PDIO of the IPT Networks, and Deploying IPv6 in Broadband Access Networks.







The following experts were helping Salman answer a few of the questions asked during the session: DSE Philip Remaker, Jim Bailey, Rama Darbha, Srinivasa Neppalli, and Pete Lumbis. All of them are top Experts on IPv6.


You can download the presentation slides in PDF format here. The Complete Recording of this live Webcast can be accessed here.


IPv6 General Questions


Q. How do I motivate higher management to drive process?

A. A good place to start is Reduced load and investment in NAT devices, compliance to Federal government requirements, and ability to scale are factors.


Q. Do the servers or routers need any additional resources in order to fulfill the IPv6 requests?

A. Routers, servers, switches, firewalls, etc, just need to be running the right software in order to handle IPv6 traffic and support the features that you need. Aside from that, there are no additional resources needed in order to process IPv6 traffic.


Q. Are there any ISPs in India?

A. India is pushing hard for IPv6, but mostly in the government and enterprise areas. ISPs have been slower than we would like. Refer to and call your provider. Mobile providers will probably lead here.


Q. Does anyone know exactly what Cisco IP6FD is and where to go in order to get documentation about it?

A. Refer to


Q. Are all Cisco devices now supporting IPv6? Do we need specific versions of the IOS?

A. You can use this URL in order to verify what features are supported, and what IOS version supports those features:


Q. Can I use Global ARIN NA IPv6 Allocation for my company in APAC or Europe? Will ISP in APAC and Europe route ARIN?

A. There is no policy that prevents you from using ARIN space in RIPE, APNIC, LACNIC, AFRINC, etc. You do need to ensure that your ISP's routing policy will support what you intend to do. Most ISPs today are more concerned about prefix length and not RIR origin. That policy could change. You can use BGP looking glasses and route servers in order to check what is happening in the IPv6 Internet regarding prefix lengths that are being routed.


Q. Will I need to have IPv6 in order to access sites participating in the World IPv6 Launch?

A. No, you will fall back to IPv4.


Q. What should I do if I cannot get to Cisco/Google/etc on the World IPv6 Launch?

A. In most cases, you either just fix your IPv6 issue or disable IPv6 in order to fix it. The troubleshooting sites (especially the ARIN wiki) can help. If your browser is using Happy Eyeballs, then there is no need to disable IPv6; it will do the magic for you.


Q. What does Happy Eyeballs do for you?

A. The Host simultaneously attempts initial connection using both IPv4 and IPv6. There is a fast response, even if the IPv6 (or IPv4) path is down. Since users are no longer trying to disable IPv6, it reduces IPv4 usage (reduces load on CGN).


Q. Who supports Happy Eyeballs?

A. Happy Eyeballs became RFC 6555 and is widely adopted. It is enabled by default in Firefox 13, Chrome, Apple iOS 4, and OSX 10.7. Everything interesting, except Internet Explorer, already supports Happy Eyeballs, or will do so very soon.


Q. How will my devices get IPv6 addresses assigned? Do I need a DHCP server?

A. SLAAC – if there is an IPv6 capable router, they WILL get an address! There is no DHCP needed except to pick up DNS server info, but it will share that info as learned from DHCPv4.


Q. What is the easiest way to get IPv6 connectivity set up for my company?

A. Use your ISP if they have it. Otherwise, use a free tunnel from a Tunnel broker. LISP is also an option. See the note on the support forums.


Q. Has Cisco designed any certification for IPv6?

A. No, there are no specific IPv6 certifications. However, we have integrated IPv6 as part of most existing certifications (CCIE, for example).

Technology Specific Questions


Q. Is HSRP IPv6 global address supported? I tried to enable Global unicast as an IPv6 address. Unfortunately, I do not have that option. However, according to the Cisco site, I should be able to set the global unicast as an HSRP address. Any reasons why?

A. At this time, only the Catalyst 6500 platform supports global IPv6 addresses for HSRP (supported as of 12.2(33)SXI4).


Q. Is MHSRP supported on IPv6?

A. HSRP for IPv6 requires version 2. You can use this URL in order to get an idea of what features are supported and the versions of code:


Q. Is OSPFv3 (OSPF implementation for IPv6) supported in Cisco Firewalls?

A. Unfortunately, it is not yet supported. Contact your account team in order to make sure that they are aware that you need this feature.


Q. What is the difference between IPv6 Multicast Address and Anycast Address?

A. A multicast packet goes to multiple destinations and is part of a reserved block of addresses in order to indicate special handling. Any anycast address is a unicast address that is routed to the nearest of a group of equally qualified devices. DNS is a common application of anycast. There are also IPv4 anycast addresses. For example, Google's DNS server is an anycast address. The IPv6 multicast address block is FF::0/8. Anycast addresses are assigned from your regular unicast address space.


Related Information


  • Books


Deploying IPv6 in Broadband Access Networks- Adeel Ahmed, Salman Asadullah, John Wiley & Sons Publications®

Deploying IPv6 Networks- Ciprian Popoviciu, Patrick Grossetete, Eric Levy-Abegnoli, Cisco Press®

IPv6 Security- Scott Hogg, Eric Vyncke, Cisco Press®

IPv6 for Enterprise Networks- Shannon McFarland, Muninder Sambi, Nikhil Sharma, Sanjay Hooda, Cisco Press®


  • WebSites


IPv6 Support Community

Slides from the Live Webcast

Webcast Video

CCO IPv6 Main Page

Cisco Network Design Central

The Internet Engineering task force

IPv6 Forum





Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: