Asterisk/DAHDI with “Dynamic T1s”

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From time to time, I find myself working with (or customers working with) “dynamic T1s”. They are typically standard T1s that terminate to an Adtran device which utilizes the channels for data (64kbps X 24) until a call is pushed inbound/outbound on the circuit. One data channel is automatically peeled off the circuit (removing 64kbps from total data throughput capacity), and reallocated as a voice channel.

Is it possible for Asterisk/DAHDI to handle a situation such as this? If I recall, DAHDI does have some data functions to it, but I’m not sure if it can handle the circuit as data (presented to kernel for iptables routing/nat), and/or if it can automagically reallocate channels for voice usage on the fly.


One thought on - Asterisk/DAHDI with “Dynamic T1s”

  • There are methods of peeling off channels dynamically to be used as data
    channels (PPP/RAS style), but not the other way around to my knowledge.
    Once an HDLC network link has been setup in the kernel’s HDLC layer, I
    don’t believe it can be shrunk or grown.