>On Fri, Mar 16, 2012 at 12:37 PM, Marcelo Pacheco <marcelo at m2j.com.br>wrote: >> Gustavo, >> >> I think you're confusing the general function of an STP with the external >> signaling network architecture used by ANSI countries. >> >> All incumbent networks in Brazil make heavy usage of STPs. >> They have lots of >> >TDM switches, and to avoid a full mesh of signaling links between all TDM >> switches that have voice trunks between them, STPs are used to aggregate >>SS7 traffic. > >STP is single point of failure unless used in pairs; using STP pairs >requires combined linkset - does ITU have this capability? don't think so >- SLS is only 4 bits; it's 5 bits in ANSI >of course it is what it is - but i'm curious how the fault tolerance vs >management ease balance out - mildly curious > >> Also STPs are also used as billing entities and for resolving LNP in some >> carriers. >> >> This seems to me to be the motivation for using STPs. > >I'm pretty sure STPs have lots of usage in other ITU countries. > >> Poland. "Lots" is a relative term. You do see them. Seems like they were >being introduced about the same time that VoIP was coming in too. Now >what? Keep building TDM or cap it and go to VoIP? I think we all know how >that is turning out. >> However they don't have a fully separate signaling network, 64kbps SS7 >> links make maximum usage of semi permanent call setups, specially for >> interconnects with other carriers (using bearer channels of existing E1 >> voice trunks). >> >> However competitive carriers use redundant soft switch architecture don't >> need STPs, since signaling flows through the IP network, without explicit >> signaling channels. > >>I fell more important than the capability of Asterisk performing as an >> STP, is much more important full linkset functionality as a regular >> signaling point. For instance, the following scenario can't be implemented >> with libss7 today: >> >> Asterisk --x-- STP A ---x--- Switch1,2,3,4,5,6,7,8 >> STP B >> >> Where Asterisk has voice CICs with all 8 switches, and all signaling needs >> to be shared across a pair of signaling links, one with each STP. Specially >> with E1s with all 8 switches can't fit on a single Asterisk box. >> >Are you describing the combined linkset? When I've seen things like this >in ITU networks, A was primary and B was alternate (used when A was not >available), instead of the ANSI model where A and B are peers and normally >used equally using a 5 bit SLS. Hi you can use one of SLS 4Bits for loadsharing between 2 Linksets to 2 STPs(you still can have 2x8 signaling links) if a ITU network needs 4 STPs they can use 2 bits for Linkset loadsharing or in every LX divide trunkgroups to two parts and for one part set STP1,2=>priority=1 STP3,4=priority=2 and other part vice versa. Regards M.Shirazi ? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-ss7/attachments/20120316/05df7752/attachment.htm>
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