Which SIP plan should you start with?

Q:

Which "good" VoIP providers are there? What should you watch out for?

A:

It is not possible to recommend a specific VoIP provider here for various reasons. The simplest advice for the Asterisk newcomer is to choose a SIP provider that offers free accounts. With this account you can then gain your first experiences. Which provider you should choose in the long term depends on many factors. Here are just a few suggestions:
  • Does your provider only offer SIP or also IAX? Do you need IAX?
  • How good is the provider's support?

Q:

Which ISDN card should I use?

A:

At first it is advisable to get to know Asterisk only in the SIP enterprise. Starting directly with ISDN is trying to do the second step before the first. If you have mastered Asterisk and understand the concept of the contexts and the dial plan, you will find tips in the ISDN chapter on choosing the right ISDN card for you.

Q:

What “normal” end devices are there and what do they cost?

A:

There is no such thing as a “normal” terminal in VoIP telephony. You have the following options for operating a telephone with Asterisk:
  • a SIP phone (the easiest option)
  • an analog telephone on an ATA gateway (this is an analog-to-VoIP adapter)
  • an ISDN telephone on an internal ISDN bus. This is often more expensive than a SIP phone without anything else to offer. Recommendation: Use a SIP telephone.
  • exotic constructs. You can z. B. hang an AB converter on an internal ISDN bus and then an analog telephone to this AB converter. If you don't have the hardware for it lying around, this constellation is not advisable.
I cannot provide any information about the prices. This would not make much sense in a book either, since the prices of VoIP telephones are currently constantly moving.

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