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Facebook Forum - IPv6

Join Harold Ritter as he takes your questions about IPv6 in our CSC Facebook community.

Harold is a technical leader with the Cisco Advanced Services Central  Engineering team. He is responsible for helping Cisco top-tier Service  Provider customers to design, implement and troubleshoot routing  protocols and multicast, for both IPv4 and IPv6, and MPLS solutions in  their environment.

This  Facechat is the first in a series from our Ask the Experts group and  will take place on Wednesday, December 15, 2010 from 10:00am – 11:00am   PST.

What is a Facebook Forum?

Facebook forum are online conversations, held at a pre-arranged time in a Facebook community.

How Do I Participate?

On the day of the event, go to

Once you go to our Facebook fan page, be sure and click "Like" to become a member of our Facebook community!


Re: December Facebook Forum IPv6

Here’s a condensed summary of our chat with Harold  Ritter.

Q:  Can you give us a brief explanation of IPv6?

A:   IPv6 is basically the protocol that will be replacing IPv4 in the near  future. It provides a lot more addresses than IPv4 (32 bits versus 128  bits address), which should enable new large network deployments and end  to end connectivity.

Q:  How can IPVs be applied to routers and VLAN?

A:   Yes. IPv6 would be configured on VLAN for instance just like IPv4  does.  They both can be configured at the same time, by the way.

Q:  According to my knowledge, applying IPv6 may give us unlimited IPs.  How will servers manage such a high occurrence?

A:  Yes lots of IPv6 addresses might cause issue on routers eventually.  Vendors will need to build bigger faster boxes or IETF will need to come  up with solution to cope with the routing table growth.

Q:  Is there any router from Cisco which supports IPv6 and dyndns configs for rdc.

A:   Pretty much all recent routers support ipv6. Not sure about the dyndns part though.

Q:  Do you see a point like IPv4 where we run out of addresses in IPv6?

A:  It is hard to imagine that we will run out of IPv6  addresses one day.  Remember that IPv6 address space is 128 bits compared to 32 bits for v4.  That is a boat load more addresses!

Q:  When do we expect the IPv4 address space to be depleted?

A:  According to most experts monitoring theIPv4 pool, we should be out at  the beginning of 2011. After that IANA will have no more IPv4 addresses  to give away.

Q:  Linksys supports dyndns for rdc and is a part of  Cisco. Why doesn’t Cisco series support it. Also would like to know  what extend of address will provide this ipv6. Thanks

A:  There is  currently no production version of Linksys routers supporting IPv6.   (Currently only Linux based versions, but these are not officially  supported.)

Q:  Just seeing how much the internet has grown over  the years, does make you wonder how much further it will grow and what  fields.

A:  more and more devices require ip addresses these day  (cars, refrigerator, thermostat, television). that is where must of the  growth will be coming from.

Q:  When can we expect IPv6 works in full swing?

A:  More and more service provider are deploying it. It is there. start to experiment with it today.

Q:  How does subnetting work with IPv6? Does it really work?

A:   By subnetting, I suppose you mean aggregation. It works pretty much the  same way as in IPv4. Bear in mind that a lot of the IPv4 concepts still  apply in the V6 world.

Q:  What is one of the top challenges IPv6 poses to the world in contrast to IPV4?

A:   One of them is the size of the routing table. It is likely to become  enormous in the near future. The fact that people do not seem to move to  IPv6 quickly is a concern.

Q:  I am trying to get a direction to where to take my studies. Any ideas of what choices I have?

A:   There is plenty of free IPv6 material at  They even have a free IPv6 certification program to get you started.   You can also get free IPv6 tunnels from them if you want IPv6  connectivity @ home.  Lastly, I would also encourage you to go and look  at the information available on

Q:  What are some of the road blocks preventing enterprise customers to deploy IPv6?

A:   There are still products in the enterprise that might still not support  IPv6. By getting started today with IPv6, you will find out about those  and will be able to talk to your vendors to fix that.  Also, the level  of preparedness in the enterprise world is a lot less than in the  Service Provider world.

Q:  Do I need new routing protocols to support IPv6?

A:   Pretty much all routing protocols supported under v4 are also supported  under v6. Most of them with a slight modification and some like ospfv3,  which required more work.  These include:  BGP, RIP, EIGRP, ISIS,  OSPFv3 and static routes.

Q:  If IPv4 it's supposed to "collapse" by Jan 2011, how soon do you think that IPv6 will be THE valid protocol?

A:   The internet will continue to work after Jan 2011. It is just that it  will be more and more difficult for Service Providers to deploy new  networks and to cope with their network growth. In 2011, IANA will be  out of IPv4 addresses. The Regional Internet Registries will still have  some address space left though. And SPs will have some provision too. So  it my take a one or two additionnal years for SP to be completely out.   Here is how IPv4 is currently distributed. IANA provides addresses to  the RIR (ARIN, RIPE, AFRNIC, LACNIC, APNIC), which in turn assign  address to end.

Thank you for participating in our Facebook  Forum.  Please feel free to share this information with friends and  colleagues.  You can view the entire conversation here:

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