Telscale SS7 card

Scope of technology


Isup to SIP GW

BSC for low-cost 2.5G BTS



The following use cases can be discussed

«Signaling gateway»
SS7/MTP to SS7/Sigtran converter
«Signaling gateway» + media
SS7/MTP to SS7/Sigtran converter + MGCP/Megaco to control RTP
«Sip gateway»
ISUP/EDSS1 to SIP with G.711 media
SS7/ISDN to wireshark-compatible file over NFS
«GSM A-interface»
There were some activities with ip.access A-interface, for which connection-oriented SCCP and some BSSAP procedures were implemeted.
These software experience could be useful, for example, to convert SIP into BSSAP and deliver rtp-packed compressed voice to the legacy TDM TRAU modules (and vice versa)

Current activities

Step 1, Goals

Step 2


Further activities

Sigtran Gateway

New hardware:

- FPGA design done

- a pilot board produced (!) and is shipped to a first customer


- SS7 stack is ready

- an initial version of the driver to interface hw to MTP2 is ready..

Gateway with fixed configuration is ready

- due to time limitations, M3UA/TCP is used in the first project


- tie RTP/SS7 to SQLite

- provide web interfacing

- store configuration to onboard flash


- support CPU-initiated FPGA reconfiguration to support switching between E1 and T1 interfaces

Full featured Sigtran Gateway

Sigtran + voice


- rtp is ready, minimal adaptations are needed

- MGCP is ready, minimal adaptations are needed

- dtmf and echo cancellation needed

Sigtran signaling/media gateway (G.711 only)

Sip gateway

- SIP is to be redesiged with oSIP

- self-written ISUP is ready

- self-written ISDN/LAPD are ready; but another supported version might be used

ISDN PRI/SIP or ISUP/SIP gateway (G.711 only)

- T.38 support

- BSSAP support

- packing voice for legacy TRAU

E1/T1 probe

Probe with wireshark compatible interface

Web-configurable probe for E1 and T1 interfaces

«Signaling gateway»

SS7 over E1/T1 is converted to Sigtran (M3UA)
Software stack for old
boards is ready. Traces can be found here. There is an alive prototype, 100% software compatible with desired
board. Mtp3/Sigtran stack is not ported yet: Mtp2 should be modified
to interface it.

25/04/2012 Pilot PCB appeared
12/05/2012 PCBs assembled 
Step 1. Expected till June'2012
The goal is Stand-alone signaling gateway. 2 G.703 E1 or T1
intefaces (T1 D4 framing). Fixed configuration (interface type and
ss7 timeslots allocation are defined by firmware; spc, ni etc —
configured inside linux image). 
To do:
- new board. PCB is under development
- mtp2 should be modified (see above)
Step 2.
The goal is Stand-alone signaling gateway. 2 G.703 E1 or T1
intefaces (T1 D4 framing). Fixed configuration. Everything is
configurable via web-browser
To do:
- store configuration data to SQLite
- web-interfaces for some light-weighted web-server
- some maintenance tools to develop (both FPGA and software)