I think the main problem is with the receive level at the AP. With a 33%, you may want to realign the CPE antenna or go to a higher gain. Also, the Amp and the splitter throw an unknow in to the equation. You don't know what kind of splatter or multipath the amp is causing and the two 180* antennas may be overlaping and causing dead zones. What kind of antenna are you using on the CPE, any amp, any router? What orientation is you CPE to the back to back AP antennas (side, front, etc...)? Have you used a SA at the CPE? At the tower? What is the receive gain of the AMP?
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of shoffman Sent: Wednesday, October 29, 2003 11:53 AM To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: [smartBridges] Figure this out if you can... Hi all, We all seem to have similar problems, don't we? Well, here is some imperical data for you that has me baffled currently... We have some customers on a tower that are having upload problems for e- mail/ VPN services. Data we know: A. High voltage lines in LOS path B. AP is a Cisco.. 100 mW transmit, 2 x 14 dbi 180 sectors, splitter (obviously), and one YDI 16dbi power gain amplifier (bi-driectional). This is the typical set-up used by BroadLink out of Santa Rosa CA. (or used to be) C. Customers have a Smartbridge AirBridge Total (ABT).. full transmit power. D. Customer shows a 87% Link quality and a -57 Rssi level. E. Cisco indicates Link quality is a 33% (yes low but usable) F. AP on Channel 6 v, large interference on Channel 9-11, no others at play. (btw, channel 1 showed same stuff) G. AP shows a packet loss transmitted to CPE at <1%, but retries at about 10% H. CPE shows packet loss at <1%, no retries. I. All negotiations are fine. (CPE 10/half, AP 100/full) J. Set to 11MBps autofallback.. negotiation always maintained at 11 Mbps. K. No bandwidth throttling.. backbone having no issue with traffic loads. L. Customer has router that sets MTU at 1460 M. RTS/CTS off, Frag 2336 (i.e. no frag threshold) OK.. so theories we have.. 1. 11 Mbps for small (negotiation packets) and working, but as soon as packets get big, the problem, re-negotiate and that breaks the telnet session with the Mail server/VPN? We tried reducing frag level, but no affect. Have not tried to lower negotiation rate. 2. Power lines causing interefence issue.. but then wouldn't we be seeing greater packet loss? 3. Other customers blocking airwaves with packets? Again, would we not see packet losses greater? 4.. Other thoughts (i.e Smartbridges not reporting packet loss correctly?) Scott ----------ANNOUNCEMENT---------- Don't forget to register for WISPCON IV http://www.wispcon.info/us/wispcon-iv/wispcon-iv.htm The PART-15.ORG smartBridges Discussion List To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe smartBridges) Archives: http://archives.part-15.org ----------ANNOUNCEMENT---------- Don't forget to register for WISPCON IV http://www.wispcon.info/us/wispcon-iv/wispcon-iv.htm The PART-15.ORG smartBridges Discussion List To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe smartBridges) Archives: http://archives.part-15.org
