Can Asterisk connect 2 offices in different countries?


We have 2 offices… 1 in Japan and 1 in Philippines… Philippines is our marketing arm, so they answer all incoming and telemarketing service. Since all our clients are in Japan, calls go thru our Japan office and we pay a big amount to forward the calls to philippines. Please view the simple diagram below…

Philippine Office Japan Office Japan Clients
DSL Connection DSL Connection
(Asterisk box 1) <---------> (Asterisk Box 2)

What we have
DSL connection in Philippines and Japan
NTT PSTN in JAPAN which allows locals to call us.

What we want to happen

  1. Can we receive calls from our clients, answer the call in Japan and be able to transfer the call in Philippines?
  2. Can we do simultaneous ring function? (when it rings in Japan it also rings in Philippines?
  3. What hardware do we need to achieve this?

Best regards,

This is definitely possible. If you want us to make this happen email me at

Asterisk can do this.
You will want to setup 2 * servers, one in philipines and the other in your Japan office. Link them via IAX2 in trunk mode.

Make sure everybody has a unique extension. Preferably, according to a pattern IE 2xxx is japan 3xxx is philippines

Then you can do something like (from philipines)
exten => _2XXX,1,Dial(IAX2/japanoffice/${EXTEN})
and your call will route from there.
End result being that you can dial between philipines and japan by extension :smile:

You can do the same thing so all japan numbers (regardless of where they are dialed from) go out through japan phone lines and all philipines numbers go out thru philipines phone lines…

As for what hardware you need:

You WILL need to set up quality of service (QoS) controls on BOTH offices to prioritize voip traffic. IMHO, this is not optional.
You MAY need hardware to connect * to your existing PBX (PRI card, etc).

Aside from that you just need a linux server on each side of the link. I would also recommend a codec like G.729 or GSM to lower bandwidth usage…

If you currently forward calls by dialing internationally between japan and philipines i would imagine this will save you many thousands of dollars in telco costs.

Thanks IronHelix for pointing me to the right direction.

To be frank I just read about asterisk 4 days ago and It feels like this new technology is an answer to our prayers. So I hope you can bear with me. I was wondering if you would be able to give me specific hardware that you’ve worked on.

In Japan Office
3 phones in Total
1 x NTT ISDN line (2 lines can go simulteneously)
1 x NTT analog line
52Mbit DSL Connection

In philippine Office
2 x 700Kbps DSL
8 x LINGO ATA Adapter (2 accounts uses Japan Virtual Number)
1 x Broadvoice (were testing the quality)

Our current setup at the moment is when a client calls to one of Japan phone numbers the call is forwarded to the Virtual Number provided by Lingo. We did it this way because Philippine DSL connection is often unstable. So when the system in the Philippines goes down, we answer all the calls in Japan but still the forwarding toll still cost us a lot of money.

What I want to know is in your expertise what exact hardware would we need in order to put the servers in place and make it up and running.

You can change whatever you want in the setup. For example I’ve just found out that there is no way to connect lingo with Asterisk so maybe I need to replace that VOIP service with Broadvoice.

Specification Needed in Japan
Asterisk needs to be able to receive calls from ISDN line and analog line
5 staff in Japan (atleast 5 phones extention needed)

Specification Needed in the Philippines
8 x VOIP (for telemarketing maybe broadvoice)
10 staff (atleast 10 phones extention needed)

Hardware Requirements
what type of Phone should I use for the asterisk PABX?
FXO or FXS cards? do I need those? if so how many?
what hardware is needed to connect ISDN?
do I need static IP in Philippines and in Japan to connect the 2 pabx?
Take note that we do not have any PABX system both in Japan and Philippines.

Again thanks for all the help!

Best regards!

:open_mouth: you forgot to include where to post the invoice for consultancy to !!
seriously, most of the info you want is on the wiki, and the rest has probably been posted here before. you just need to look for it.

First a suggestion- if you dont have much experience with unix/linux or *, consider hiring somebody to set it up. It will probably go much smoother and be more reliable… I know the first few times I wrote * dialplans they were a total mess. both drwho and baconbuttie have been around here for a while and I’m sure they can get you set up very nicely and with great ease/speed.

Also FWIW this is an example setup. The real trick is the integration, making this work. You can’t just buy phones and plug them in…


First you dont need a static ip. You can use a dynamic dns service which will work pretty well. FXO card plugs into a LINE, FXS card plugs into a PHONE and provides the phone with dialtone. FXO/FXS are only needed for dealing with POTS analog phones/lines. Asterisk uses your system’s network card for VoIP.

Japan Office
Router for DSL with quality of service control
Server running Linux and Asterisk
Digium TDMxx card (one fxo) for analog line
1x BRI (isdn) card, there’s a few of them around.
for staff- VoIP telephones of your choice (I recommend AAstra or SNOM hardware).

Philippines office
Router with QoS control
Server running Linux and Asterisk
8x softphone (xten eyebeam, sjphone, idefisk, etc) for telemarketers. Uses existing computer and a headset. Cheaper.
10x VoIP telephone of your choice for staff.

All VoIP numbers would register to * box in Japan, which would allow reinvites to Philippines. There would also be an IAX2 trunk for extension dialed calls. Calls ring * box in Japan, get IVR etc, then get forwarded to philipines if they have to talk to a rep down there. 4 digit extensions would be assigned to all agents and users, anybody could call anybody else with 4 digits regardless of what office they are in.

Another thing to consider- VoIP sort of abandons the concept of a ‘line’. IE, you do not need separate accounts for each user. There are many VoIP companies that will sell/port you a DID (phone number), over which any number of concurrant calls can be handled. You can also dial out and be charged a low fee per minute per call, in the USA its usually 1-3us cents per minute per call. This may or may not save you money.

Also, as I said before, this is easy to talk about, but hard to do. Asterisk is like a tub of Legos, you can make something cool out of it but you have to know how. If your business is going to depend on it, consider hiring a pro to set it up right.

Hope that helps!

Thanks very much for all the information. You guys are right after searching through it I realised that there are people who had nightmares setting up * .

You are right, if anyone of you are in the Philippines or here in Japan who could help me out I’m all ears. We are prepared to spend money on the project but I want the cost to be reasonable as well. That’s why the information you put here will help me a lot in determining what will be needed to make it work.

Yes, you guys are right, the information you put in here can be considered as a consultation. If you guys ever drop by in Japan PM me and the beers are on me.

Again thanks very much!

if you cant find somebody, that wont really matter as much… as long as you can physically assemble the boxes the rest can be done remotely over ssh. Alternatively, if you contract with somebody you might be able to arrange for them to build the hardware, configure it and then ship it to your sites. Most of the stuff I do is IRL, but I have done a handful of online contract work too. So even if you can’t find a local guy, don’t let that stop you :smile:

also has a nice listing of * techs…

Hello IronHelix,

I’ve tried to research more about the BRI Cards you told me about to connect the ISDN but it seems like it doesn’t support Japanese ISDN. If you ever come across of an ISDN hardware that can be used in Japan please do let me know…