Feature #2812

Build mixed ISDN / analog telephone network

Added by laforge over 1 year ago. Updated 3 months ago.

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We should build a mixed ISDN = analog telephone network that we can use to interconnect the client-side modems/TAs with the BBS-side modems/TAs.

The network should offer analog as well as digital (S0, S2M) ports.

Rather than going for an old, bulky, power-hungry and proprietary PBX like the Alcatel 4400 series used by the POC, I think we could try to use a more modern approach by using LCR with E1 and quad/octo-S0 boards for the digital side, as well as some a/b adapters, as well as SIP and associated TAs.

  • S2M / PRI is needed to connect devices like Livingston PortMaster3 or other "bulk access" devices that can handle 64k ISDN asd well as [up to] V.90 analog
  • S0 busses are needed for interfacing ISDN cards/TAs on BBSs and Clients
  • L1oIP can be used for virtual E1 trunks between LCR instances in distributed setups
  • SIP with G.711 can be used to interconnect with public SIP operators for dial-in/dial-out
  • consumer-grade PBXs like ISTEC 1003/1008/media can be used for attaching analog modems
  • SIP<->telephony voice gateways like Cisco VGxxx can possibly be integrated, offering 24/48/30 voice lines

The resulting network should be mounted in some portable rack/chassis so it can be transported and set up at events, as needed.


#1 Updated by laforge 3 months ago

  • Status changed from New to In Progress
  • % Done changed from 0 to 20
I bought an "Auerswald COMmander Basic 2" PBX for that purpose. It currently has the following cards installed:
  • 1x E1 port (for connection to e.g. a E1 RAS server)
  • 4x S0 ports (for ISDN cards, each S0 port can host two 64k dialup)
  • 8x S0 ports (for ISDN cards, each S0 port can host two 64k dialup)
  • 8x a/b ports (for analog modems)
  • 8x Up0 ports (like Uk0 but different, not directly usable without converters)

#2 Updated by laforge 3 months ago

I also obtained a "Livingston Portmaster 3", which is a RAS (dial up server). AFAIK in its current configuration it has capacity for 1 E1 interface (30 channels) which can either all be used for RAW-IP or PPP dial-up. It also contains dsp boards for terminating analog modem communication [which is received over ISDN B-channels on the E1).

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