Would you recommend VoIP for calls from Asia to all over the world?

Question

Telephony

Hello!
My company is located in Vietnam and provides design services at a distance. In the near future, we are planning to enter new markets, in connection with which there was a need to create an international call-center.
I have never dealt with this before, so I would like to get recommendations from knowledgeable people.
The initial data is as follows:
- Calls from Vietnam around the world (incoming, outgoing, from a widget on the site, if possible)
- Virtual PBX with an easy and preferably free connection (since this will all be tested in light mode for now)
- Free outgoing calls for clients via number (800)
By the way, one more question follows from the last paragraph - will these be different numbers for each individual country or can there be a single number? Isn't the billing too high in this case?
Thank you.

Answer 1

Zadarma, which was advised above, is not the best option, because it has servers in Germany and Latvia, ping from Vietnam will be 200-300 ms, and such a large ping is bad for telephony.
And yes, Zadarma is a very good option.
There are no 800 numbers uniform for all countries. If you need calls all over the world, then it is cheaper to place a callback form on the site, in which the client enters his phone number, and the system immediately calls him back and connects him to the call center. We at thoughtology.rf did this. It will turn out much cheaper than a 8-800 number: firstly, there is no monthly fee for this number, and secondly, incoming 8-800 is 2-3 times more expensive than outgoing from a regular number.
Here, for sure, you need to look for IP telephony providers with servers in Japan, China, Vietnam, India, Singapore with normal routing from Vietnam (as far as I know, Asia has problems with this). Because there is hardly a provider in local markets that, like Zadarma, will provide a free (or for little money) PBX with a lot of features, then you will probably have to take SIPs without PBX and install Asterix and other bells and whistles on a VPS near Vietnam. For example, in Singapore, digitalOcean for $ 5 a month should have enough of the simplest server to handle a small number of calls (I have never worked with asterixes, but, as far as I read about the experience of other people, on such a weak server 1-3 simultaneous incoming / outgoing must withstand.
Your task is interesting, if you need help, please contact: [email protected] If you find something, let me know, I'm interested.