Setting Up QoS for 3CX under Windows 7

Mark Berry June 2, 2011

As mentioned in the previous post, getting endpoints to apply QoS tagging is only half the battle. We also need the PBX to apply tagging on outbound packets.

Basic QoS Setup on a Cisco SG 200 Switch

Mark Berry May 27, 2011

I recently purchased a Cisco SG 200-26 gigabit switch to upgrade the office infrastructure. This is a “lightly-managed” switch with a web interface. Here’s what I’ve learned so far about setting up basic Quality of Service (QoS) for Voice over IP (VoIP).

PBX in a Flash as a Virtual Machine, Take 2: Hyper-V

Mark Berry February 16, 2010

Back in November 2008, I blogged  about Setting Up PBX in a Flash, Part 1: Configuring a Virtual Machine. That article discussed running PBX in a Flash (PiaF) under Microsoft Virtual PC or Virtual Server 2005. Within a couple weeks, I abandoned the virtual machine approach and published Moving PBX in a Flash from a Virtual to a Physical Machine.

Recently I’ve been testing Microsoft’s free bare-metal hypervisor, Microsoft Hyper-V Server 2008 R2. Especially now that Hyper-V supports Red Hat Enterprise Linux, could Hyper-V be the answer to virtualizing PiaF on a Microsoft platform?

Let’s try it and see what happens.

Keeping Asterisk Traffic Inside the VPN

Mark Berry January 9, 2009

No DTMF

I’m setting up a new PBX in a Flash (PiaF) machine running Asterisk 1.4.21.2. I’m testing it by calling in with SJPhone across a VPN (the PiaF machine is at a client site). When I dial 7777, I get my top-level IVR, but when I press a number, nothing happens. If I dial into a voicemail box, the * and # keys have no effect. It seems PiaF is not hearing my DTMF tones at all.

Unexpected Public Traffic

Moving PBX in a Flash from a Virtual to a Physical Machine

Mark Berry November 24, 2008

After running PBX in a Flash (PiaF) in a virtual machine for a few days, I had a couple issues:

The system would generate an occasional message “TSC appears to be running slowly. Marking it as unstable.” This issue did not keep the PBX from running.

Voice quality was sometimes jittery. In a call, it would sometimes “cut out” (like a bad cell connection). In voicemail, even listening to the pre-recorded prompts, there was frequently some garbled-sounding audio.

Getting Asterisk to Bridge Audio

Mark Berry November 22, 2008

In my original PBX in a Flash setup, Asterisk is set to “listen in” on calls. One advantage of this is that it can then respond to commands sent from a phone keypad during the call, e.g. to transfer or record the call. However, it does add processing overhead. If your devices support it, you can tell Asterisk to butt out of your conversations, allowing connections to “bridge” directly between endpoints and avoid going through Asterisk. Here’s how.

Setting Up a Polycom IP 430 Phone with FreePBX

Mark Berry November 20, 2008

I want to use a true SIP phone for my office phone. I was initially attracted to the Polycom SoundPoint IP 430 because of its support for electronic hookflash with my Jabra GN9350 wireless headset. By using a special adapter cable, I can answer the phone from the wireless headset without the need for a mechanical handset lifter.

Things I Wish I’d Known

Setting Up PBX in a Flash, Part 4: Configuring a Linksys SPA3102

Mark Berry November 6, 2008

I’ve just posted a series of articles on selecting a VoIP PBX and setting it up under Microsoft Virtual Server. To read the series from the beginning, see Getting Into VoIP.

Setting up an Analog Terminal Adapter (ATA) for a VoIP system is normally something you do while configuring the PBX. However, since it is configured as a separate device using its own web interface, it seemed to warrant its own blog entry.