This is just a proposal how a scalable cost-effective solution can look like. It is not implemented yet, but the goal is to work out a right approach. I developed quite similar things in 2003, when I interfaced ip.access BSC to S-12 and AXE-10.
This is a piece of operator infrastructure, desired to be sold to MNO. In Russia it also assumes certification procedure, held by authorized center. On Mon, Mar 25, 2013 at 1:16 PM, John Wu <[email protected]> wrote: > Hi Dmitri, > Have you developed the solution connect private GSM network to operator > core network? > But this should be allowed by the local operator, right? > > > On Sat, Mar 23, 2013 at 5:09 PM, Dmitri Soloviev <[email protected]>wrote: > >> Hi >> >> we've got several requests to extend existing GSM networks with our radio >> equipment, where ip transport is appreciated. >> >> Please take a look at my vision of interfacing A-over-ip to a legacy GSM >> A-interface. >> >> Building blocks: >> >> 1. OpenBSC with ip.access-compatible A-over-ip interface >> >> 2. MGCP-controlled transcoder, built with Sangoma D-series cards. Can be >> assumed as a shared resource, available for several BSC instances. >> http://www.sangoma.com/assets/docs/datasheets/en/d500.pdf >> >> 3. TelscaleSS7card - a stand-alone signaling and media gateway, with 2 E1 >> and 2 Ethernet interfaces, running embedded linux on board. >> It converts A-over-ip to A-interface, acts as MGCP call agent for BTSs, >> transcoders and other telscaleSS7cards. A card is implemented in PCI form >> factor, but bus is used just to provide power supply. >> In other words, a card can act either as a combined SG+MG, converting >> A-over-ip into SS7 and RTP into E1 timeslot, or just a MG, converting RTP >> into E1, without any impact on the host system. >> >> >> When a [signaling gateway + call agent] detects ASSIGNMENT_REQUEST or >> HANDOVER_REQUEST, it stores cic value. As soon as ASSIGNMENT_COMPLETE or >> HO_REQ_ACK is detected, it builds RTP chain that unites >> BTS<->transcoder<->media_gateway. The chain is broken after the call is >> finished. >> >> Depending on the chosen cross plane, 4U 19" industrial PC can carry >> several BSC instances with transcoding, serving about 20 E1 interfaces (ea >> about 80 ARFCNs). Performance requirements for industrial PC cards are also >> negligible: computer will run OpenBSC and configure transcoder cards, being >> controlled by means of MGCP. >> >> >> >> Best Regards, >> Dmitri >> > >
