From: [email protected] [mailto:[email protected]] On Behalf Of Joao Roberto S G Ferreira Sent: Sunday, March 29, 2009 12:21 PM To: [email protected] Subject: [DSTAR_DIGITAL] After all, how much is the real minimum Internet bandwidth for a gateway?
I did all the tests of our gateway (PY2KCA) in my place with a 6MB DWN/1MB UP cable Internet connection. Everything worked fine. We only have the VHF module installed, since we want to install more D-Star repeaters and, for economical reasons, no extra modules will be installed in near future. And there is not internet in have Internet access will be available thru the radios. The main use will be voice contacts. The only way to obtain Internet access in our repeater site is from a wireless ISP with equipments in the same building. The problem is this ISP only provides low bandwidth connections. For this reason, I monitored, for a week, the bandwidth in the PY2KCA server, at my place, to quantify how would be the minimum. For my surprise, with one connection only (REF001), an average of 8kbps was used for maintain a perfectly good QSO. Added a DV Dongle user, the average rose to 17kbps. If this measure proves to be true, the 128kpbs connection from the ISP would just work fine. So we took the server to repeater site and it's worked just like in my place. My questions: 1) Why the minimum bandwidth requirement is so high if works with much less? Maybe in order to sustain every possible module using the maximum connection, 128Kbps Internet access over 1.2GHz, etc? The minimum that Icom presents is a minimum for a maximum configuration. That would include 3 voice repeaters and a data all in use at the same time with a couple of multi-cast sessions going on. Indeed the minimum bandwidth is much less. We've found out that US Cellular systems, even dial-up can be sufficient for a single module system. But that doesn't include any DVDongle users or multi-cast sessions. The problem is that often a slow connection also includes some significant latency, and latency isn't great. And if you have a remote terminal session open are or doing OS updates, the voice signal may be hampered. 2) Working with this low bandwidth in our gateway may harm the D-Star network in any way? This low bandwidth connection made all difference for us in be or not working like a gateway in the D-Star. I'm sure much more ham clubs, having the very same limitation about Internet access in the repeater site, will like to look closer to this case. Not reall, you just have broken signals if the bandwidth isn't sufficient. Any toughts? 73 from PY2JF Admin for PY2KCA - Americana - SP - Brazil [Non-text portions of this message have been removed]
