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Some virtual servers changed

Some virtual servers changed

Some virtual servers in cloud-MSS system have been changed, please pay attention to these items.

STUN server

Each virtual SIP server will enable STUN feature. For example, if the SIP server address is “”, its STUN server can also be the same address. That means “” is also its STUN server address.

Now we suggest “” by default. It is a simple public STUN server for all virtual SIP servers. Of course, you can still configure your virtual SIP server address as your STUN server.

SMTP server

In voice-mail feature, we need a SMTP server to send emails with attached audio files. Each virtual SIP server can be configured with customers’ own SMTP servers. But we find it could make several problems. For example, most customers try to use Gmail SMTP server. Gmail SMTP server requires that you need enable POP/SMTP firstly, and grand other access. Most customers don’t know how to do that.

So we disable SMTP server configurations. All voice mails will be sent from our own SMTP server. ¬†Most important is that you will need check your spam box if you cannot find voice email in ‘inbox’.

Refined SMTP library

Refined SMTP library

In voice mail feature, MSS need use SMTP library to send emails. Since MSS can embed Python script functions, it is easy to use Python-smtplib to send email. That’s what we done and it works well, we are satisfied with it.

But smtplib is too old ( in python 2.7) to fit some modem SMTP servers’ requirements. It also has a shortage. It is synchronous. That means it can block thread when sending a email, then its performance is poor and cannot fit our requirements in cloud system.

Something is changed, we want MSS to be better, so we develop a new SMTP library to send voice mails. This SMTP library is asynchronous and can work perfectly with most SMTP servers. And, it is written in C/C++ language.

We upgraded MSS V23 and cloud-MSS to replace python-smtplib with this new SMTP library.

Hope you can enjoy latest versions.

By the way, since MSS V23 has been released for several months and we got very better result, we think it is time to release new LTS version which is V24  and new stable version which is V25 in the end of this year or in the beginning of next year.