Posts Tagged ‘comcast’

HBO NOW DNSSEC Misconfiguration Makes Site Unavailable From Comcast Networks (Fixed Now)


Wow! Talking about insanely bad timing…  yesterday at Apple’s big event, HBO announced “HBO NOW”, a new streaming service available for only $15/month that will give you access to all HBO’s content.  This was great news for those people who want to “cut the cord” and not have to pay for a cable TV subscription Read more…

March 10th, 2015 by | Posted in DNSSEC | Tags: , , | 3 Comments

Great news! New IPv6 Web Sites:,, and IPv6

Very cool news in Comcast’s announcement today that they launched IPv6 support for: Naturally I had to check… and sure enough, using the IPvFoo plugin for Chrome, there in the upper right of… was the green “6” showing it is connecting over IPv6: Now, clicking on the green six in my Read more…

July 22nd, 2014 by | Posted in IPv6 | Tags: , | 1 Comment

Comcast’s Speedtest Now Breaks Out IPv6 Speed Vs IPv4 Speed

Comcast XFinity Speed Test

A tip from John Jason Brzowski let us know that Comcast’s Internet speed test at now performs speed tests over both IPv6 and IPv4 and shows you the results separately.  This is a public test that anyone can use, regardless of whether you are a Comcast customer or not.  Perhaps obviously, for the IPv6 test to Read more…

February 5th, 2014 by | Posted in IPv6, Statistics | Tags: , | 9 Comments

Comcast Launches IPv6 Trials For Business Customers – Sign Up Today

comcast business logo

We were very pleased to see news yesterday on Comcast’s corporate blog about the launch of IPv6 services for businesses. Comcast’s John Jason Brzowski wrote there that: Business Ethernet customers have had full IPv6 service and support in place for them since the beginning of 2013. IPv6 trials are about to get underway for our Business Internet customers Read more…

April 30th, 2013 by | Posted in IPv6 | Tags: , , | No Comments

Comcast Publishing Domains Failing DNSSEC Via Twitter

Comcast DNS Twitter account

How do you know when a domain is failing DNSSEC validation? What if there was a way to let the broader industry know about these validation failures?  The folks over at Comcast’s DNS team have been trying an experiment for a while in posting these DNSSEC validation failures publicly to Twitter at: If you Read more…

March 29th, 2013 by | Posted in DNSSEC | Tags: , , | No Comments

Video: What are “Negative Trust Anchors” for DNSSEC?

What are “negative trust anchors” for DNSSEC? What function do they perform? Why do we need them? In this video, Dan York interviews Jason Livingood about his Internet-Draft on this topic and answers these and other questions: The Internet-Draft can be found at: Jason and his co-author are seeking comment and would appreciate feedback Read more…

March 26th, 2013 by | Posted in DNSSEC, Videos | Tags: , , , | No Comments

Comcast Formally Launches IPv6 Home Networking Pilot

This is huge! In a pair of blog posts today Comcast formally launched its IPv6 “Home Networking Pilot”: IPv6 Home Networking Pilot Market Launch Begins, by Jason Livingood IPv6 Home Networking Pilot Market Deployment Technical Details, by John Jason Brzozowski As I explained in an earlier post about this impending launch, support for home networks Read more…

April 26th, 2012 by | Posted in IPv6 | Tags: , | No Comments

Comcast Enables IPv6 For Xfinity and Xfinity TV

Great news out of Comcast this week related to IPv6 – they have now made two of their major content portals available over IPv6!  From their page on April 10, 2012: The newest part today moves two of our major portal sites to IPv6, including Xfinity andXfinityTV. This critical move was made possible via close cooperation Read more…

April 12th, 2012 by | Posted in Case Studies, IPv6 | Tags: , | No Comments

Comcast Releases Detailed Analysis of DNSSEC Validation Failure

Did you see all the tweets and mentions on the web last week about Comcast apparently blocking NASA’s website on their network? While it made for great headlines, the truth was that there was an error with the DNSSEC signing of the domain and now that Comcast has deployed DNSSEC-validating DNS servers those DNS Read more…

January 25th, 2012 by | Posted in DNSSEC | Tags: , | 4 Comments

Comcast Gives 17.8M Customers Access to DNSSEC-validating DNS Servers

In a rather huge step for DNSSEC deployment, Comcast, the largest Internet Service Provider (ISP) in the United States, announced that they have completed the deployment of DNSSEC and have given their 17.8 million customers access to DNSSEC-validating DNS servers. Their post states in part: As of today, over 17.8M residential customers of our Xfinity Read more…

January 10th, 2012 by | Posted in DNSSEC | Tags: , | 2 Comments