VoIP Tech Chat

Cisco recently announced a Denial of Service vulnerability within the SIP implementation of the Cisco IOS Software. Cisco devices running affected Cisco IOS Software versions that are configured to process SIP messages are affected. The vulnerability allows a remote attacker to reload a device and/or execute remote code.

Cisco recommends removing SIP support unless needed. “If the affected Cisco IOS device requires SIP for VoIP services, SIP cannot be disabled, and no workarounds are available. Users are advised to apply mitigation techniques to help limit exposure to the vulnerabilities. Mitigation consists of allowing only legitimate devices to connect to affected devices. To increase effectiveness, the mitigation must be coupled with anti-spoofing measures on the network edge. This action is required because SIP can use UDP as the transport protocol.”

The full advisory is reprinted below: Read the rest of this entry »

Cory Andrews posted a great “tech tip” on the VoIP Insider blog detailing how to convert a Cisco SCCP phone to SIP.

Whether you’re a Cisco fan that finally realizes Asterisk can provide better PBX services (at a lower cost) or just someone who happens to have a bunch of Cisco Skinny VoIP telephones laying around, converting the firmware to SIP can make the Cisco phone compatible with many VoIP systems.

But, don’t take my word for it… go to the VoIP Insider and read Cory’s tech tip. Give it a shot and tell us what you think.

What you VoIPing 'bout Willis?

Yes, you guessed it correctly. In today’s article, Diff’rent Strokes will be used as a metaphor for VoIP. Why? The correct question is “Why Not?” And the answer… well that’s simple — Diff’rent Strokes is the perfect metaphor. Take for example these classic lines from the show’s theme song:

Now, the world don’t move to the beat of just one drum,
What might be right for you, may not be right for some.

Classic. Pausing for Trivia… do you know which 80’s sitcom star wrote these lyrics? If you said Growing Pains actor and Canadian sensation Alan Thicke, you’d be right… but, as usual, we digress.

Those working within VoIP, and contrary to many medical reports there are people still working in the industry, have many flavors and styles of VoIP products to choose from. Although opinions vary, there really is no “right” or “wrong” product line. Selecting your VoIP implementation is an individual choice that is determined simply by what works best for you. Read the rest of this entry »