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The IPv6 Implementation Action Plan (by TechWiseTV)

Isn’t real time to think about your company’s (and personal) ¬†network migration to IPv6?¬†

That’s why today I want to share this (quite long but) very interesting video produced by our ¬†TechWiseTV¬†friends Robb Boyd & Jimmy Ray.

They have interviewed Cisco’s IPv6 experts around the world and walk us thru the¬†key steps to successful implementation.¬†The security implication are of course covered as well as co-existence mechanisms such as NAT64.

And not to forget Cisco’s own real-world experiences with IPv6, from the backstage of World IPv6 day last June ’11. See more links below.

If you wish to attend a deep dive workshop on this topic, feel free to contact me at jpa@cisco.com

World IPv6 Day: A Watershed Moment Towards a New Internet Protocol

Cisco.com users on World IPv6 Day 5 to 10 times more likely to use IPv6 than visitors to other websites

Fosdem 2011, IPv6 on Cisco’s Wireless

Over the last week-end, a group of Cisco’s volunteers, assisted the FOSDEM to get a proper network up and running; this is our story !

What is FOSDEM ?

FOSDEM, the Free and Open Source Developers’ European Meeting, is the biggest free and non-commercial event organized by and for the community. It’s taking place in Brussels for the last 11 years.

The event has been growing over the years and now welcome ~5000 visitors for two days of keynotes, speeches, lightning talks covering many many FOSS projects.

A group of volunteers from Cisco Belgium is helping FOSDEM to build the Internet access network, using Wireless.

What is special with this network ?

The audience you have at FOSDEM is very fund of network access, and also pretty knowledgeable, so not the common user base you’d find in an enterprise or another event. So pressure on getting it right and highly secure on the¬†infrastructure¬†side is key. An example of this was being able to detect and react nearly instantly to rogue DHCP/DNS server trying to poison the network. The Cisco Security toolkit embedded ¬†in the Catalyst switches prevented this to be possible.

What was deployed and how was it configured ?

WAN Edge

We were provided by Belnet with a one Gigabit uplink within the Internet Exchange located on the ULB campus in Ixelles. The peering was done using an ASR 1004 running IOS-XE 3.1(2) and fiber uplink.


From the ASR a fiber, provisioned on the ULB underground fiber path, is going to our main comm’s room and terminated on a 12 ports 10Gig ¬†fiber switch, a¬†Catalyst 3560E-12D.¬†And from the comm’s room, all 4 access switches, being a mix of¬†24 and 48 10/100/1000 PoE+ switches (3560-X series)

The Access-points were a mix of 1142 and 1252 abgn, depending of the site-specific needs.

Management and monitoring

On the Wireless, we were using the combined ULB and FOSDEM WLAN’s into one single WLAN. Maintaining full benefit of centralized wireless controllers for management, monitoring and reporting.

Reporting of network statitics and monitoring was done using Munin and Cisco WCS. We were also serving our own DNSv6 (& v4) server for local users.

Lastly we tested IPv6 only connection using DNS64 and NAT64 built on FreeBSD kernel. This has be proven to work really well and as such we are thinking of providing only IPv6 addresses at next year conference, but ¬†ūüôā


The complete config used for the main router has been published at the Support Community website

Finally let’s the results speak for themselves:

Over the w-e, we had 4171 unique users on the WLAN and a peak at 1672 concurrent users on Saturday around 16.00 CET

Interesting to note is that amongst those¬†4171 unique devices on the FOSDEM network,¬†¬†595 were Mac/iPhone/iPad, 452 were HTC devices, 341 Nokia, 56 Samsung, 23 RIM (Blackberry) and 806 were using an Intel chipset…

What about IPv4 to IPv6 ratio ?

We have seen about 1.85k IPv6 link-locals (==total devices whith IPv6 enabled) while 2.18k IPv4 addresses were cached at the router; which means 84% devices had IPv6 enabled !!

And a total of 1.08K global IPv6 addresses( == IPv6 used); that is 49.5% actually went to the v6 Internet.

So would said IPv6 was lagging adoption ?

If you want to have a look at how it was last week-end, check the video below:

IPv6 Unified Communications


In this post I want to update you with what is available today when implementing Unified Communications on an IPv6 network.

What you need to retain from this post, is that IPv6 is available today when deploying Cisco¬†Unified Communications, and it can be enable in a few easy steps. (Let’s agree that this would be first done in a lab though ūüėČ

Configuring the UC server

The Ethernet interfaces of the UC server can be configured both in CLI and GUI [fig. 1]. This configuration is at OS level. An important note here is that Cisco UC-OS is a Common Application Run-time for most existing Cisco UC products, meaning that once a feature is available in it, it can be exposed and used by any UC applications.

with CLI, enable IPv6 :

set network ipv6 service enable

set a static IPv6 server address :

set network ipv6 static_address <addr> <mask>

review IPv6 address settings :

show network ipv6 settings

Or using the UCOS GUI, as showed below. This is done in OS administration; under Settings > IP > Ethernet IPv6


Configuring the CUCM, at the application level for phone and intra-cluster communications

The IPv6 address can be used for both phone to UC server and between server communications [fig. 2]. This is required configuration for every server in the cluster where you wish to use IPv6.

Either a AAAA record or IPv6 address can be used for the IPv6 name. In case of AAAA, your DNS (v4 and v6) will need to provide resolution for it.

under System > server


Enabling IPv6 for IP Phones to Server communications

You will first need to enable IPv6 cluster-wide, and then have the option of setting your signaling and media preference parameters either cluster-wide [fig. 3] or per group of phone [fig. 4]

under System > Enterprise Parameters


under Device > Device Settings > Common Phone Profile


SIP trunking

SIP trunk can be configured directly on CUCM or on an IOS VoIP gateway or SBC (like CUBE). More details on SIP trunks are covered in this previous post.

SIP trunking is fully supported in both IPv6 only and dual-stack depending of your needs. Both SIP Early Offer or Delayed Offer with ANAT or without ANAT are supported.

Today the recommended addressing mode would be dual-stack leaving the option to select one or the other thru ANAT.

IPv6 destination address and SRV records can be used in configuration.

A few work on ANAT:  Alternative Network Address Types (RFC 4091)

ANAT is an application layer mechanism that permit the offer of both IPv4 and IPv6 address in the SIP invite (mid:1 and mid:2) as well as indicating a preference (group:ANAT 2 1) where here mid:2 is the preferred choice.

SIP INVITE with SDP ( Early Offer)

a=group:ANAT 2 1
m=audio 18356 RTP/AVP 0
c=IN IP4
m=audio 16462 RTP/AVP 0
c=IN IP6 2001:db8:aaaa::987:65ff:fe01:234b

Then in the SIP answer  200 (OK) with SDP, shown below, the remote end replied saying, ok I can do IPv6, as group:ANAT 2 indicate. And to further indicate this, the UDP port number for IPv4 is set to zero.

a=group:ANAT 2
m=audio 0 RTP/AVP 0
c=IN IP4
m=audio 16462 RTP/AVP 0
c=IN IP6 2001:db8:bbbb::123:45ff:fe32:191d

So ANAT gives us an application aware, very flexible way to inter-connect multiple call-agents (could be both in your enterprise or between you and a service provider or another enterprise)

In conclusion

UCv6 is available today, and despite full feature set are not fully available yet, you can already start testing and validating this deployment. IPv6 only IP phones can be deployed today and be a starting point to help you save your IPv4 addresses.

Cisco has about 10 customers using it in production environment today. And we expect to provide a full featured UCv6 solution within the next 2 years.


IPv6 – the next generation challenge for Service Providers

John Chambers on IPv6 at Google Conference :

As we near 2012 when the last IPv4 address is assigned to a new subscriber, SPs must maintain and continue to accelerate growth. Billions of new devices such as mobile phones, portable multimedia devices, sensors, and controllers will demand Internet connectivity in the next five years. SPs need a solution that supports unconstrained global accessibility.

CGv6 is designed to help SPs deal with these challenges. With CGv6, SPs can:

  • Preserve investments in IPv4 infrastructure, assets, and delivery models through the use of Large-Scale Network Address Translation, along with private IP addressing.
  • Prepare for the smooth, incremental transition to IPv6 services that are interoperable with IPv4 using high-performance Tunneling technologies, combined with Large-Scale Address Family Translation.
  • Prosper through accelerated subscriber, device, and service growth enabled by private IP and IPv6.

CGv6 extends the already wide array of IPv6 platforms, solutions, and services. We’re introducing a Carrier-Grade Services Engine (CGSE) for the CRS-1 family, as well as supporting new features for the ASR family. Cisco CGv6 helps you build a bridge to the future of the Internet with IPv6.

For more IPv6 related information, make sure to visit :


John Chambers on IPv6 at Google Conference

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