Pierre’s Lab

The common standards are Session Initiation Protocol or SIP, H.324, H.323 and proprietary solutions - the most know being Skype.

H.323 and H.324 are multimedia standards designed to provide converged services - video telephony services, voice and data.

SIP is the standard for basic voice over IP calls - Vonage desktop uses SIP. There are several standardization groups working on bringing these standards together.

Often for a home user, proprietary solutions like Skype are the only solution. Small and large business will go with SIP, H323 or H324 depending on their needs (Voice, Video and Data).

The simplest and easiest setup is using one of the available PC-based solutions like Skype, MSN, Yahoo or Vonage. These use almost any PC connected to the internet over DSL or cable. It works on dialup but bandwidth limit becomes quickly an issue.
The PC needs a good quality audio card and speakers and microphone or a headset - which I strongly recommend. Calling PC based members (Skype, MSN, Yahoo) works well and is free. Calling regular phone numbers costs money and/or requires additional equipment. Vonage gives you a 10 digit number in your area with 500 monthly minutes the monthly cost is $9.99. Skype offers Out-calling and In-calling plans which can be expensive - no free minutes.

The next level is the consumer VoIP system designed to replace a single regular phone line. These are offered by many large telephone and cable companies but also by third party such as Vonage. They require an ATA (Analog Telephone Adaptor) connected to your internet connection. ATA extract voice packets and provide a PSTN port for a regular phone or PBX. These routers manage traffic load to handle voice call quality which is as good as a regular land line.

Small business setups can grow to I-PBX solutions. I-PBX have more features than PBX and can cost as much as PBX. Three main solutions exist:

• All IP from end to end. There is no phone line from the Telco but an internet access to connect to the VoIP provider. Moving from an old PBX to an all IP can be costly and even more if the local wired network is old and doesn’t support QoS.
• IP to PSTN, this often a good upgrade solution. The existing PBX is replaced by an I-PBX, the Telco is replace by a VoIP provider but the internal phones network is kept. This solution doesn’t work if the old PBX uses dedicated non-PSTN phones (Rohm, Nortel…)
• PSTN to IP a good phone and switch upgrade solution. The Telco lines are kept and feed an I-PBX. The phone network is replaced by IP phones - this solution can be costly if the local wired network is old and doesn’t support QOS.

AR1688 is a programmable chip, used for low cost IP phones, it replaces the famous open source PA1688. The architecture is the same, with 8-bit controller for VoIP protocol and 24-bit DSP for voice compression algorithm.

If you compare both chips, the AR1688 has more CPU processing speed and higher and better integration. The IP phone based on AR1688 has improved performance, better voice quality, more features at lower cost.

AR1688 specifications and cross reference with the PA1688:

• CPU clock speed: 48Mhz, the PA1688 ticks at 22Mhz
• DSP runs 60MIPS, the PA1688 runs 33MIPS
• Integrated high-quality audio codec, the PA1688 need external codec
• Integrated SRAM, no external SDRAM needed, the PA1688 needs 1×16 external SDRAM
• RoHS ready
• ICMP response time for 1472 bytes: 10ms, the PA1688 response 21ms)
• TFTP server data put through: 140kbytes/s
• MD5 48 bytes encryption calculation: 4.8ms, the PA1688 needs 9.9ms)
• Software API use open source SDCC compiler, the PA1688 uses commercial Keil C51

Bottom line, the AR1688 is faster, better and cheaper to integrate.

Did it again! Looking for a good VoIP solution, I search stores, eBay and other market places unfortunately I didn’t find anything affordable with all the features I needed.

I searched among Asian suppliers and found several with quite extensive products.

Now, I’m the proud owner of a very powerful and reliable VoIP network Based on High Link products, the network works like a Swiss clock. IP phones are GF302 built on the famous AR1688 the model selected is not POE so they need external power supplies.

The gateway is a good rock solid GW202O with 2 Ethernet ports, 2 FXS and one FXO. The network support analog phone as well as IP phones and PSTN.

These products are so good, I decided to import some and sell them first on eBay and why not later in a B&M.

I’ll keep you posted on my selling progress.

Being a happy Vonage customer since long time, I wanted to look at several options to get a soft phone line for my computer.

Vonage offer a monthly $9.99 solution using the XT-Pro interface which is not the best one, the contact list is awful, the speed dial doesn’t work unless you use a 3 digit scheme etc…

I tried Skype IN and OUT which are not free but offer nice features that Vonage lacks. I called France - free with Vonage, Few cents a minute with Skype.

Quality wise, Skype is far behind Vonage between echo, cracking, silence and other weird noises Skype’s quality is not really land line quality. Vonage offers a quality almost as good as a land line and it’s free to almost all countries in Europe, Canada, Mexico and Puerto Rico.

Between Vonage and Skype you have to choose, quality and features. Vonage’s interface lacks features and Skype lacks quality.