The B-Channel Switch (TSMUX) is an A8619 Active Interface Module that connects bearer channels from up to 8 E1/T1 interfaces and works in conjunction with the Dual port E1/T1 interface.  It is compatible with the different A8619 Network Emulator applications, which connect the incoming and outgoing bearer channels according to the signaling information.  The network emulators manage the bearer channel allocation and control the B-Channel Switch whenever a connection is established or taken down.

Additionally it can be used for clock synchronization when two or more interfaces need to use the same clock source, i.e. when A8619 Network Emulator is used as a Local Exchange (V5, SS7 or ISDN).  The module is fully software configurable - the user interface allows the clock source to be selected from the different E1/T1 interfaces in the system.

Hardware Configuration
The TSMUX Active Interface Module requires one slot in an A8619 chassis unit.  

Note:  The TSMUX master port entry in the user interface is set to use the card that is assigned to be clock source.  A TSMUX cable connects the interface designated to be clock source to the TSMUX via the 1^st socket on the module.  Additional interfaces are connected via the other sockets.

There are two different types of TSMUX cable with different connectors, dependent on the version of the Active Interface Modules installed (IOB/IMB). Under certain circumstances the AIM-IOB cables are more sensitive to interference.

V5 Local Exchange Network Emulator
The V5 Local Exchange Emulator is configured for eight subscribers; four ISDN and four PSTN.

V5.1 Mode
According to the V5.1 specification the bearer channel allocation is static.  The V5 LE emulator is configured as:

- TSs 01, 02, 03, 04 for ISDN phones with Layer 3 addresses 1 – 4 respectively.

The IUT (Access Network) must be configured accordingly.

V5.2 Mode
The time slots are dynamically allocated; the V5LE emulator and the IUT (Access Network) use the BCC signaling to exchange information about which time slot to use..