Archive for category VoIP Security
Full disclosure: I am good friends with Phil Zimmermann, co-founder of Silent Circle. He and I worked together for many years to publish his ZRTP media security protocol as an RFC in the IETF standards body. I also helped him with his Zfone Project. I’m also friends with Jon Callas, Travis Cross, and others at Silent Circle, who collaborated with Geeksphone to produce the Blackphone.
After the Blackphone was announced back in February in Barcelona, I ordered one as soon as they started taking orders, and have pretty much just been killing time ever since then. I even had a false alarm delivery the other week when I was at the IETF conference inToronto. Another package with an address that had “Black” in it arrived, and I jumped to the conclusion that it was my Blackphone. Instead, my Blackphone arrived the day I was in Chicago at ClueCon, on a Security Round Table panel with Phil and Travis.
My first impressions are quite positive: the packaging is good, the phone is nice to hold in the hand. If anything, it feels lighter than I expected. And it is black. Included accessories are USB cable, charger with US and European plugs, and a headset.
I’ve been using Silent Circle for a while now on my iPhone, so I recognized the Silent Phone and Silent Text apps. Silent Contacts was new to me, as were the other pre-installed security apps.
It took me a little while to get Silent Phone and Text working. I had forgotten that I had to look up the Product Keys to get the Silent Circle Ronin code to activate the service and create my account. The Silent Circle apps are similar to those on my iPhone although the user interface is inscrutable. Why does it show one grey dot when I’m calling then switch to three green dots when I’m connected and ZRTP has been authenticated? What does “Secure to server” mean? Hopefully this is an easy fix to the UI to make it understandable.
Next, I need to try out SpiderOak and Disconnect.Me. Also, I haven’t put a SIM in yet. My friend James Body has given me a fantastic Truphone travel SIM that I really could have used last month during all my travels…
Look for a future post on these topics. As always, questions & comments most welcome.
On Saturday, I gave a presentation and demo of ZRTP at Hackfest 2013, organized by the Washington University in St. Louis chapter of ACM (Association of Computing Machinery) .
A group of about 60 undergrads had gathered in Urbauer 211 to learn about hacking and try it out. I gave a short presentation about ZRTP, the media path keying protocol for SRTP invented by Phil Zimmermann.
I was fortunate to serve as the editor of the ZRTP specification, which was published as RFC 6189 two years ago. I showed how ZRTP allows users to detect the presence of a MitM (Man in the Middle) attacker by checking the Short Authentication String.
Here is a PDF of my presentation.
Then I used the Jitsi open source voice, video, & chat application to demo ZRTP. Emil Ivov, founder and chief developer at Jitsi answered my ZRTP call, and we checked the SAS. The sequence of steps used to secure the voice & video session is shown in this animated GIF.
Afterwards, I gave away a copy of Counting from Zero, my technothriller that incorporates elements of ZRTP, hacking, exploits, and zero-day attacks.
We then spent the rest of the afternoon playing with Metasploit on an isolated network of virtual Windows machines. It was an interesting day. Just like at IETF meetings, the biggest excitement of the afternoon was when the cookies arrived!
Perhaps at next year’s session, we can try out VoIP hacking tools such as SIPvicious!
As 2011 draws to a close, I wanted to take a moment to thank everyone who has helped me this year. It has been an amazing year! Here’s a short list of my highlights:
– In January I gave a SIP Tutorial for the FCC staff in DC. It was a great event, and hopefully I will get another chance to do it again in 2012. The FCC has lots of VoIP and SIP work to do with the transition of the PSTN and E911 to all VoIP. Hopefully we can soon end the ridiculous subsidies for rural telephone service and instead use them to subsidized high speed Internet service for rural areas. My friend Henning Schulzrinne was just appointed Chief Technology Officer, so I know the FCC is in good hands technically. I also enjoyed giving the SIP Tutorial in Miami, Sydney, and Austin.
– In February I published my first novel, a Techno thriller about a massive attack on the Internet that gives this blog its name – Counting from Zero. Little did I know how much hacking and security stories there would be in 2011. Some have even called 2011 the Year of the Hactivist, which is hard to argue with. Overall, I couldn’t be happier with the response to the book. Thank you do much to anyone who has read, reviewed, tweeted, or blogged about it – I am very grateful. Look for more book news in early 2012…
– In March I participated in my first robotics competition. The experience was amazing, and I look forward to the start of another build season in just over a week!
– In April, the ZRTP VoIP media security protocol was published as an RFC by the IETF, after 6 years of hard work. Editing this document is my small contribution to making the Internet more secure. Here’s to more adoption and deployment in 2012.
– In May the RTCWEB Working Group was chartered by the IETF. The work is progressing slowly but steadily. I expect more progress in 2012, and hope for some strong security to be built into the protocols – lets show that we have learned something over the years…
– In June, I participated in the first ever SIP Network Operators Conference or SIPNOC for short. It was a great success and really shows how SIP has grown up. I am privaleged to have another term on the Board of Directors of the SIP Forum. With the publication of SIPconnect the SIP Trunking recommendation, the business use of SIP continues to grow and expand.
– In November, I has my first experience as a cricket coach. My son started the Priory Amateur Cricket Association or PACA as a club at his school. It has been a blast so far helping the boys learn the basics of cricket. They have done a great job, although we need to reduce the number of no balls! In 2012 we plan to play a one day match against a local cricket club.
So, here’s to 2011 – it was definitely an interesting year! I hope it was a good one for you and yours. Here’s to 2012!
I spent all last week in Austin, Texas at the Internet Telephony Expo, ITEXPO conference. In addition to giving the SIP and RTCWEB Tutorial and having a board meeting of the SIP Forum, I moderated a security panel at the 4th Generation Wireless Evolution 4GWE conference. It was a great panel, with Patricia Steadman, CEO of Telesecret,a company founded by Phil Zimmermann to commercialize the ZRTP media security protocol, and a good friend and former colleague from Avaya, Andy Zmolek from LG Electronics.
As I enjoyed the cool and damp weather back in St. Louis (the opposite end of the weather spectrum from last week!), I was elated to discover that my novel “Counting from Zero” was ranked #12 on Amazon’s Computer Network Security sales list! (Of course, this ranking changes minute-by-minute, so it might very well be ranked a bit lower when you read this.) I mark this as yet another milestone with this book, my first attempt at fiction. To have it doing so well in a ranking filled with security text books is very exciting!
I was also thrilled to see two other books I greatly admire ranked just above me at #7 and #9: The Art of Deception: Controlling the Human Element of Security and The Art of Intrusion: The Real Stories Behind the Exploits of Hackers, Intruders and Deceivers by Kevin Mitnick and William Simon: I use both these books as references in my book. I was thinking of Kevin all last week during my travels as I finished reading his newly released memoir Ghost in the Wires: My Adventures as the World’s Most Wanted Hacker. It was an amazing read, and I highly recommend it. Maybe I’ll post a full review here one day soon.
My original goal with “Counting from Zero” was to teach the fundamentals of computer and Internet security, but to do it in a non-traditional way. I had written one other book on security, “Understanding Voice over IP Security”. Its sales have not been great, compared to some of my other SIP and VoIP books. One reason is perhaps that security books tend to be dry, and a little theoretical, not well-connected with real life. In “Counting from Zero” I tried to invent a plot that would not only teach security, but help motivate it. I set out to create a character, Mick O’Malley, who would initially seem over-the-top in his security, but have the subsequent action and events make him seem more normal, and the rest of us who barely give security a thought the strange ones.
I have greatly enjoyed the reviews of the book, and those complementing my characters, writing, plot, etc. But I enjoy hearing the most that a reader learned something from the book.
If you have an interest in Internet or computer network security, my book will help explain some basic concepts and help motivate the topic. If you have ready my book (thank you!) and learned something useful from it (fantastic!), I’d love to hear from you…
So how does this fit with SIP, which I’ve spent much of the last 10+ years working on? SIP or Session Initiation Protocol is the IETF protocol for establishing voice and video sessions over the Internet. SIP is used all over the Internet today, and in private networks. It is used by service providers for VoIP (Voice over IP) networks, and it is used by enterprises for their internal PBX (Private Branch Exchange) networks. It is also in a number of applications and services including Skype In and Out and even Apple’s Facetime (kind of).
This topic will continue to be discussed in the standards bodies, and also in next month’s ITEXP Internet Telephony Expo. I’m excited to be giving an all-day SIP Tutorial with Henry Sinnreich in which we will introduce and teach SIP and also the principles behind the RTCWEB effort and how SIP and RTCWEB relate. You can find out more about the tutorial and register using this link.
One of the other hot topics of RTCWEB is security, and I have written and spoken out about the need for privacy – protection against eavesdropping on voice and video communication. A media security protocol such as ZRTP would be an excellent choice, but there are other options. Unfortunately, there is a contingent that wants to permit unencrypted voice and video media from the browser. But that is a topic for another day…
Hope to see some of you in Austin, Texas at the SIP Tutorial on September 15. 2011!
SIP, or Session Initiation Protocol, is used on the Internet for making phone calls. In technical terms, it is a signaling protocol.
I was involved very early in the development of SIP. It was my introduction to the world of open Internet standards, something I believe very strongly in. Let me explain.
In the early days of computers, everything was proprietary, which in thus situation means that it was unique and different for every brand and type of computer. As hard as it is to imagine today, there wasn’t even a common standard for representing characters – a simple text document would have to be converted in order to display correctly (some examples, for those of you interested were EBCIDIC, Baudot, and ASCII – which became the standard?). The same was true for networking – each manufacturer had their own protocols and interfaces – it was virtually impossible (by design) to connect them together.
Fortunately we have come a long way since then, and the Internet, with its open standards helped a lot. I’ve enjoyed working on open standards with the Internet Engineering Task Force or IETF for quite a few years now.
SIPconnect is a great example developed by a not-for-profit that I am proud to be involved with, the international SIP Forum. SIPconnect is a standard that helps connect a telephone network with a business phone system, known as a PBX in the business, when the connection is made over the Internet instead of old fashioned wires and leased lines. It isn’t very exciting but it solves an important problem for both service providers and businesses. In short, it does what a standard does best, and works behind the scenes to reduce costs and increase efficiency.
Here is good article by Russell Bennet entitled “Finally, a SIP Trunking Standard that Makes Sense” which gives some good background on PSTN Trunking and SIP Trunking with SIPconnect.
Unfortunately, there are lots of examples today where standards are not being followed, and single-company, proprietary systems are in use. Some of the most prominent examples relate to some of the most popular hand held and personal electronic devices used by many people (including myself!)
But standards are always evolving, and business models change – today’s successful proprietary lock in is replaced by next year’s standard. Technology is both fast moving and fast changing.
For today, I’m happy to celebrate the publication of this SIP document and remember all my friends and colleagues who have worked so hard on it over the years!
As we jokingly say as we raise our glasses, “SIP, SIP!”
RFCs or Request For Comments are the publications about how the technical details of how Internet works. They go all the way back to the earliest days of the ARPANET, used to share information among a small group of researchers. RFCs are published by the RFC Editor and cover Internet fundamentals such as TCP, IP, and SMTP. My first RFC was one for Session Initiation Protocol or SIP which was published as RFC 3261. Since then, I have published 14 others, but I’m most proud of this one.
ZRTP is a security protocol for providing privacy for VoIP calls over the Internet. It was invented by Phil Zimmermann, who invented PGP (Pretty Good Privacy) for email encryption in the 90’s. When I met him in 2005, he had an idea how to encrypt voice calls and some very rough prototype code. I helped him turn it into a protocol, and wrote the outline of the document that was published today. I’ve been the editor of this document for the past 5 years.
I think ZRTP is the best way to secure voice and video over the Internet. The reasons are a bit technical, but perhaps I’ll attempt explain why in another post. In the meantime, Phil Zimmermann’s Zfone Project web page has some good points in it.
Oh, and there is one other reason why I’m proud of this document – I came up with the name ZRTP. RTP stands for Real-time Transport Protocol. And of course, Z stands for Phil! It was a joke at first, but it kind of stuck.
ZRTP even makes an appearance in my techno thriller novel, Counting from Zero. The protagonist, Mick O’Malley uses ZRTP to ensure that all his voice and video communication is private, thwarting those who would like to wire tap his communications.
It has been a lot of work getting this RFC published, and I’m quite proud of the work. And over the years, I’ve become good friends with Phil, which is a real bonus.
Today I’m going to have a mini celebration – happy first birthday ZRTP, RFC 6189!