Matt Holdrege <matt@ascend.com> wrote: > > Who is the carrier(s)? Do they have CCS signalling to Denmark? You need to > arrange for a clear channel 64 connection which should give you fast setup. I only know for sure that Bell Canada's ISDN is served by Stentor. I have no idea what type of equipment is used either here, or in Denmark. I do know that I get 64K for local calls. This is the only long distance setup I have had to deal with so far. The following item offers some insight. If all this is true, I am very disappointed. John_Marks@ascend.com wrote: > > You may already know this part. In North America the phone system is much > older than most of the rest of the world. In order to pass signalling > information over the link at the same time as data and voice, the > Robbed-Bit Signalling technique was developed. Remember each of the > channels on a T1 is just an eight bit slice of the entire signal. > Robbed-Bit Signalling essentially stole a bit from each of channels in > which to insert one bit of signalling info; after receiving a number of > channels a signalling word would be put together. Because seven bits are > used for data and one for signalling the best we could get out of it was 56 > Kbps. In Europe after the War, they decided to replace older equipment with > new "out-of-band" signalling systems, hence the E1. This new system used > one of the channels for all of the signalling and left the remainder to > operates at full eight bits per channel or 64 Kbps (They also increased the > number of channels to 32 of which 30 where for data/voice use). This lent > itself to our PRI type circuits. Ok, what has this to do with a call from > Canada to Denmark. > > To maintain 64 K through-out the North American telephone system for PRI's > we had upgrade many of the trunks to an "out of band" signalling technique. > The problem is all the legacy equipement and software that is geared toward > 56K, Robbed-Bit. We developed Signalling Systems 7 or SS7, this puts a > parrallel system just for carrying the signals. Although, this the least > expensive option, it is a substantial "upgrade" cost, so major centres get > done first and then connections between cities within each telco's serving > area. Next, the various telco's then assign agreemnts to pass SS7 > information between themselves and lastly, the older international trunks. > It was just year and half ago that you could not get 64 K between Toronto > and Vancouver. You still can't get 64 K to all the U.S., carriers from Bell > Canada or the other Stentor members. > > Why the 56 KR designation, I am not 100% sure. The difference between the > 56K setting and the 56KR setting is that the 56KR stands for "Restricted" > and enforces the 1's density of the channel. The 56KR setting is generally > used with AT&T manufcatured switches. Most likely this is what they have in > Denmark to tie into the North American trunks, or you are going through a > U.S. carrier at some point and they have an AT&T switch (If you orginate > inside Canada it won't go to the U.S -- CRTC rules and all). > > I can't explain the long set-up time, but your assumption is probably > right. As for ping times, again the propegation delay created by the > distance will be the major factor. I am not sure where you are based but, > the data must travel from your sight through a bunch of curcuits and > perhaps carriers, then to the Transalantic carrier, over the Alantic, > probably to Britian. From there is must work its way to Denmark, ( from > Denmark to Greenland if that is the case). Who knows how many kilometers of > wire it is going through. A general rule of thumb to get the propegation > delay, is take the number of kilometers of wire/fibre, divided by the speed > of light. For a ping since it is a round trip double this number. This > value of course will be faster than the actual, but it should give you a > feel for the delay due to distance. > > I hope this helps > > John Marks > Sr. Systems Engineer > Ascend Canada Inc. > > > >From: Larry Williamson <larry@mitra.com> > >Date: Sun, 23 Nov 1997 23:42:14 -0500 > >Subject: (ASCEND) Dialing to Denmark from Canada requires 56KR ? > >We have a small branch office in Denmark. I have had no luck > >connecting our 1800 to their p50 except using 56KR. > >Is this to be expected? > >A couple of other things too... > >Ping times seem to be quite long. I guess this makes some sense given > >the distance between us. Typical ping times are in the 160ms range. > >Call setup takes about 11 seconds. Again, given the distance, I guess > >this is reasonable. > >Larry > > > > > ++ Ascend Users Mailing List ++ To unsubscribe: send unsubscribe to ascend-users-request@bungi.com To get FAQ'd: <<A HREF="http://www.nealis.net/ascend/faq">http://www.nealis.net/ascend/faq</A>> </PRE> <!--X-MsgBody-End--> <!--X-Follow-Ups--> <HR> <STRONG>Follow-Ups</STRONG>: <UL> <LI><STRONG><A HREF="msg11019.html">Re: (ASCEND) Dialing to Denmark from Canada requires 56KR ?</A></STRONG></LI> <UL> <LI><EM>From</EM>: Matt Holdrege <matt@ascend.com></LI> </UL> </UL> <!--X-Follow-Ups-End--> <!--X-References--> <STRONG>References</STRONG>: <UL> <LI><STRONG><A HREF="msg10898.html">(ASCEND) Dialing to Denmark from Canada requires 56KR ?</A></STRONG></LI> <UL> <LI><EM>From</EM>: Larry Williamson <larry@mitra.com></LI> </UL> <LI><STRONG><A HREF="msg10903.html">Re: (ASCEND) Dialing to Denmark from Canada requires 56KR ?</A></STRONG></LI> <UL> <LI><EM>From</EM>: Matt Holdrege <matt@ascend.com></LI> </UL> </UL> <!--X-References-End--> <!--X-BotPNI--> <HR> <UL> <LI>Prev by Date: <STRONG><A HREF="msg11019.html">Re: (ASCEND) Dialing to Denmark from Canada requires 56KR ?</A></STRONG> </LI> <LI>Next by Date: <STRONG><A HREF="msg11017.html">Re: (ASCEND) Problems using an 1800's K56 modems with uucp</A></STRONG> </LI> <LI>Prev by thread: <STRONG><A HREF="msg10903.html">Re: (ASCEND) Dialing to Denmark from Canada requires 56KR ?</A></STRONG> </LI> <LI>Next by thread: <STRONG><A HREF="msg11019.html">Re: (ASCEND) Dialing to Denmark from Canada requires 56KR ?</A></STRONG> </LI> <LI>Index(es): <UL> <LI><A HREF="maillist.html#11018"><STRONG>Main</STRONG></A></LI> <LI><A HREF="thrd249.html#11018"><STRONG>Thread</STRONG></A></LI> </UL> </LI> </UL> <!--X-BotPNI-End--> <!--X-User-Footer--> <!--X-User-Footer-End--> </BODY> </HTML>