How Many Extension/SIP Trunks can asterisk handle?

  1. How Many Extension?
  2. How Many SIP Trunks?
  3. PSTN Trunk Support? If yes, How many PSTN Trunks Supported?
  1. No practical limit (note you probably meant single hop SIP devices, as extensions are just abstract addresses in Asterisk).

  2. Asterisk doesn’t distinguish between SIP “trunk” and “extensions”; they are both SIP peers.

  3. Limited by hardware, not Asterisk.

Real limits will be on the number of simultaneous calls, in terms of OS limits on open file descriptors, and UDP port numbers, and in terms of CPU and network load.

In general, you should only expect answers to sizing questions in terms of specific configurations that are known to work. System load can vary by orders of magnitude depending on how you use it.

thank you very much