Graves On SOHO Technology

While I ordered the DoorBell Fone back in August the fact of our extreme Houston summer kept me from completing the installation. The buried wire run out to our gate was broken and there was just no way I was going to bury a new wire in 100+ degree heat. This past weekend I was able to find the time and temperature to complete the installation.

The largest task was to completely replace the wiring from the central closet in our house out to the gate. I replaced the old-skool solid copper pair with a length of Cat-5 cable. Using Cat-5 is a bit of future-proofing. It means that I can change to a POE-powered network device at the gate without replacing the cable again.

For the moment I’m using only one pair from the Cat-5 wiring, connecting the DoorBell Fone remote unit to the controller in the wiring closet. The total cable length is about 80 feet.

Read the rest of this entry »

While I have been basically offline for the past week, I took some time while awaiting one of my flights home to read some news. That little exercise revealed that the Freeswitch community call this past week featured Phil Zimmermann describing VoIP encryption and more specifically his ZRTP protocol. Happily, the recording of the call was put online Thursday.

Phil is of course one of the leading lights in the world of encryption. The call features Phil speaking plainly and openly about the need for encryption and the manner of its implementation in ZRTP.

The call remains a community call, so it goes off in various directions at times, including a little Asterisk bashing. However, Phil makes a good effort to keep the call informative, making it a great listen for anyone interested in voice security.

A short while ago I briefed you on my years-long search and utterly frustrating search for the perfect, affordable, SIP/IP-based door phone, preferably with video. Having set aside that lofty goal, I resigned myself to retain primarily the “affordable” aspect of the prior set of specifications, which lead me to look for an analog door phone.

There are many analog door phones available from companies like 2N, Adtran, Avaya, Bogen, NEC, Panasonic, Valcom & Viking, just to name a few. For my project, based upon some advice from friends, I settled upon Door Bell Fon as a suitable choice.

As a vendor I selected Home Controls since they had inventory, a good price, and seemed to have some experience with the product. My order included the DP28C control module, a DP38 NBZF door station and DP38 BXFS surface mount box. The total cost was right around $300.

Read the rest of this entry »

My efforts at blogging began on November of 2007. Since then I’ve covered a variety of topics, mostly relating to issues of home office communications and network infrastructure. In all that time one item has remained on my honey-do list; the intercom or access phone at the front gate. At long last, I’ve ordered the parts to finally deploy some kind of solution, even if  it’s not exactly what I was hoping for.

The first question to answer is why do we need a gate intercom in the first place?

Working from a one-man home office one of the biggest inconveniences I face is taking deliveries from courier companies. Like many homes, we have a fenced yard, so the delivery person cannot get up to the font door to knock. Even if they did, my office is in the back of the property, in what was once a garage apartment, so I wouldn’t hear them knocking on the front door.

Further, with our two Labrador Retrievers occasionally in the yard there’s some sense in keeping the delivery people at the gate. It’s safer, both for them and the dogs.

There’s a button for doorbell at the front gate, but it hasn’t worked in years. The doorbell mechanism in the house was long since removed, given my equally longstanding intention to install something better. I’ve been searching for “something better” for quite some time. That something better has proven difficult to find.

Read the rest of this entry »

Sunday’s episode of On The Media from WNYC had considerable coverage of the evolving News Of The World story. In addition they had a full segment on the state of voicemail security in the US.

In the segment on voicemail security Executive Producer John Keefe tried one of the common “hacks” on his own cellular service. Using an online service he spoofed his caller ID such that the cellular carrier thought he was calling from his own cell phone number from his own handset, a circumstance where they may not require the use of the voicemail PIN code.

They go on to give an overview of the state of basic voice mail security with some of the major US carriers. Apparently only AT&T and Sprint by default allow caller ID based bypass of the requirement for use of a PIN code.

It’s good to see someone looking beyond the face of the scandal to consider how the cellular carriers blatant disregard for even the simplest matters of security allowed the exploits occur.

I learned about this in a post by Shawn Merdinger to the VOIPSEC Mailing List. It’s a Google Tech Talk going way back to the beginning of what we now call “VoIP.” The presentation is by Danny Cohen and Stephen Casner. It’s a long video, but it’s very interesting.