Osmocom Libraries » libosmo-abis

h1. libosmo-abis

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h2. General description

This is a library containing common/shared code regarding the A-bis interface between BTS and BSC.

It implements drivers for mISDN and DAHDI based E1 cards, as well as some A-bis/IP dialects.

h2. Source code

To obtain libosmo-abis, you can use the following git URL:

<pre>

git clone git://git.osmocom.org/libosmo-abis.git

</pre>

h2. Input Drivers

There are currently the following input drivers available:

h3. misdn

This input driver supports the mISDN code as it is present in mainline linux-2.6 kernels.

It uses the in-kernel LAPD implementation, and is thus bound to some restrictions.  Specifically,

you can only have one signalling timeslot (D-channel) in every E1 line, which may cause problems

with multi-BTS or multi-TRX setups (particularly in the case of Nokia A-bis)

You have to configure which E1 timeslot is to be used for signalling by module parameters, e.g.

<pre>

modprobe hfcmulti dslot=1

</pre>

will configure TS1 as signalling.

h3. misdn_lapd

This input driver supports the mISDN code as it is present in mainline linux-2.6 kernels.

However, unlike the "misdn" driver, it runs LAPD in userspace, as part of libosmo-abis.

In order to be able to use it, you will need to make sure the mISDN kernel driver does not

configure any timeslot to signalling, e.g.

<pre>

modprobe hfcmulti dslot=-1

</pre>

(notice the "-" in front of 1 to indicate "no signalling timeslot").

h3. dahdi

This driver supports the DAHDI (formerly known as zaptel) out-of-tree drivers for e.g.

the various Digium and Digium compatible E1/T1/J1 cards.

h3. ipa

This implements the ip.access A-bis/IP multiplex protocol.

h3. hsl

Experimental driver for support of the [HSL_Femto]