Yes, a few switches acts in that way, but it's very uncommon. As I tested a few years ago, EWSD in V11 (V13 and V15 works good) and 5ESS V14 can fail with that behavior. Regards, Gustavo On Jul 3, 2009, at 8:27 PM, Marcelo Pacheco wrote: > I've seen one certified switch for Brazilian ISUP/SS7 (MTP is > identical > to ITU-T) the switch is from Digitro that delivers FISUs only 25% of > link idle time, 75% of idle octets (considering FISUs idle octets) are > flags. That switch talked with sucess with Ericsson AXE, Nortel DMS, > Vectura (operating as an STP), Tropico RA and some others, without > link > instability. > > Anyhow, libss7 using dahdi mtp2 shouldn't suffer from this issue, as > well as chan_ss7, as both generate FISUs not stop correctly. > > Regards, > > Marcelo Pacheco > > Kristian Nielsen wrote: >> "Gustavo Marsico [Gmail]" <gustavomarsico at gmail.com> writes: >> >> >>> It's talking about Japan: >>> >>> Note: In the ITU-T Japan variant, signaling link quality is >>> checked by the >>> continuous transmission of flag octets (8-bit bytes) rather than >>> FISUs; >>> FISUs are sent only at predefined timer intervals (e.g., once >>> every 150 >>> milliseconds). >>> >>> If you live in Japan can make sense that, but in ITU world it's >>> just like as >>> Kristian's said. >>> >> >> Yes, I meant ITU SS7. Forgot about the multiple variants ... >> >> Here is the relevant quote from ITU Q.703: >> >> 11.2.2 For the basic error control method, the priorities are: >> Highest 1. Link status signal units. >> 2. Message signal units which have not yet been >> acknowledged and for which a >> negative acknowledgement has been received. >> 3. New message signal units. >> 4. Fill-in signal units. >> Lowest 5. Flags. >> >> So fill-in signal units are sent unless some serious error prevents >> sending >> anything but flags. >> >> Don't know about any other variants of SS7. >> >> - Kristian. >> >> _______________________________________________ >> --Bandwidth and Colocation Provided by http://www.api-digital.com-- >> >> asterisk-ss7 mailing list >> To UNSUBSCRIBE or update options visit: >> http://lists.digium.com/mailman/listinfo/asterisk-ss7 >> >> > > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > asterisk-ss7 mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-ss7
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