So which is better Cisco SPA2102 or Obi202? Almost identical

[Tuan]

I tried to do a search for spa2102, but didn't get result I wanted.  On the outside, they look identical.

I heard about the Cisco's echo issues, but not sure if they fixed it.  Obi202 seems to be the favorite.

[Tuan]

I actually got both units and tested them out.  The result is that the Linksys SPA2102 has faster connection speed.  I wonder if the Linksys has a faster chip.

Here's the test:

With both units on the same network (using ATT Uverse 2wire modem with built-in router) and both using voip.ms (same codec g711u), the Linksys SPA2102 seems to respond faster at reaching the destination after dialing the same test 888 toll free number.  I timed the connection after dialing the last digit to the time the Virtual Receptionist picks up on the other end.  I dial 10 times each for the Obi202 and the Linksys SPA2102 to make sure the results are consistent.  The Obi202 (firmware 3.0.1 build 3932) takes about 5 seconds, whereas the SPA2102 takes about 2-3 seconds.

I wonder if Obi202's new firmware would reduce the connection time.

[Mango]

I consider the OBi202 the upgrade of the SPA2102.  The SPA2102 is now out of production.  You may be interested to know that some of the staff from Sipura (designers of the SPA2102) now work for Obihai.

The OBi202 has a lot of advantages over the SPA2102.  In particular the SPA's router is slow by today's standards - its maximum speed is about 7.5 Mbit/sec.  The OBi202's call routing features are also much more powerful; for example you can register to up to four service providers (including Google Voice) and route incoming calls any way you like.  You mar also set up many voice gateways for routing outbound calls.  The OBi202 also allows you to use devices such as the OBiBT, OBiWiFi, and OBiLINE.

You're correct that some users reported echo when using an older PAP/SPA device.

The only real advantage the older PAP/SPA devices have is a configurable jitter buffer.  This may be useful if you want to use a monitored alarm system, point-of-sale credit card processor, or any other device that sends data over the phone line.

As for Tuan's test, the results are probably related to the dial plan.  Wireshark would tell you for sure, if you care to examine what is going on in more detail.

[carl]

I never experienced any problems with connection speed of Obi 202 or Obi 100. Fast.

[Tuan]

Dial Plan of the Obi:

(1xxxxxxxxxx|<1559>[2-9]xxxxxx|<1>[2-9]xxxxxxxxx|011xx.|xx.|*xx.|(Mipd)|[^*]@@.)

Would this cause any delay?

I agree with Mango that the Obi has more settings, but my main concern is the quality of call.  Right now, the spa2102 is giving me the lower latency compared to the Obi.  If you guys are not having issues, I have to reset my Obi to factory to give it another shot.

Carl:  How fast is fast?  Can you give me the number of seconds that the other side rings?

[ianobi]

Tuan,

That digitmap is adding a 2 second delay even when the number dialled is an exact match. There are two ways to send out a number with no delay:

1. add "S0" to the end of the rule such as :
(1xxxxxxxxxxS0|<1559>[2-9]xxxxxx|<1>[2-9]xxxxxxxxx|011xx.|xx.|*xx.|(Mipd)|[^*]@@.)
Now an eleven digit number starting with 1 will be processed with no delay. Use "S0" sparingly. The above works, but it can cause problems.

2. The 2 second delay is caused because although you have an exact match in the original digitmap after dialling say 1xxxxxxxxxx, you also have rules in the "Indefinitely Matched" state. "xx." is always Indefinitely Matched as it accepts any number formats. "[^*]@@." also acts like "xx." as far as digits are concerned. If not needed I would get rid of some rules and end up with:
(1xxxxxxxxxx|<1559>[2-9]xxxxxx|<1>[2-9]xxxxxxxxx|011xx.|*xx.)

The OBi Nerdy explanation is in the ObiDeviceAdminGuide around page 185:
Matching Against Multiple Rules in Digit Map

[Tuan]

Mango:  You were right regarding dial plan.  Thanks.

ianobi,

I changed the dial plan to option 2 and the connection time delay went away.  As far as call quality goes, both the Obi202 and the Cisco spa2102 are as good. 

After this fix, I'd have to rank the Obi202 higher than the spa2102 since it has more options.

Thank you so much for posting the new dial plan.  You're awesome. 

By the way, the dial plan I posted was suggested by voip.ms.  Yours is evidently better.

[ianobi]

To be fair to Obihai, they usually put these three rules at the end of their digitmaps to cover all possibilities:

xx. Matches any number not picked up by any other rule, but adds a ten second delay.
(Mipd) Allows user to dial an ip address from the phone keypad. Does anyone ever do this?
[^*]@@.) Allows for sip uri dialling, if your voip provider allows.

I'm guessing that voip.ms simply takes the standard Obihai digitmap and adds in its own required rules.

The moral of the story is - if you don't need a rule, then ditch it!

[QBZappy]

@Mango,

The only real advantage the older PAP/SPA devices have is a configurable jitter buffer.  This may be useful if you want to use a monitored alarm system, point-of-sale credit card processor, or any other device that sends data over the phone line.

This might be of interest:
Re: Trouble with Credit Card terminal but faxing works great

Modem is sensitive to jitter buffer adjustments during a call. Your OBi can detect FAX tone and will switch off jitter buffer adjustment when FAX is detected (it might even switch to T.38/FAX Relay if the call peer also supports it). That makes your FAX work better.

However there is no Modem signal detection support.
There is a new feature in the latest firmware (3.0.1.4109) that may help (do a f/w upgrade first).
It allows you to disable jitter buffer adjustment for the next outgoing call, by dialing a *code (of your choice). This is what you can do: Add a Star Code (under Star Code Profile) like this:

*01, Modem Call, set($Noji1,200),set($Noec1,1),set($Cdm1,3)

The 3 set() commands tell the obi to do the following for the next outbound call:
1. Disable Jitter Buffer Adjustment, and use a fixed jitter buffer length of 200 ms
2. Disable Echo Canceller
3. Use only G711u and G711a codec

Replace *01 with any code you like, as long as it does not conflict with other codes.
Then dial the target number and see if the modem call works better.
Note that this only controls the OBi; the quality will still be affected by the behavior of the call peer and any network impairment. Good luck.

I don't know why you thought that obihai wasn't showing you any love. It looks like the Jitter Buffer is now configurable. Well that takes one thing off the obihai to do list. Let's see the next thing on that to do list is the openvpn embedded client, yes that's what I hope they work on next. 

[Mango]

I have seen this and am very happy that Obihai implemented this feature.