Normally when you see 1 second pings it is because there is a throttle somewhere in the path (usually never in the microwave side) - perhaps your cable/dsl/t1 router has a limit and you or someone else is exceeding that limit, thus causing the LLOOOONG turnarounds. If it gets worse, you'll start dropping packets too. Check the proper operation of your packetshaper. And remember that many of these attacks are symetric, while many lines are a-symetric - so they can fill the return path (say 128 kbps) with your FAST downstream path (say 1536 kbps). If your packetshaper isn't set to kick in until people are hogging the 1536 number above 768, lets say, then the problem can be there well before that point - you'll get 128 down and 128 up - and nothing else will fit in the line.
Get etherereal and sniff the line - use NTP to time lock your ethereal machine to the bridges and pcs involved so you can coordinate the exact time down to the second (or beyond) when this happens. see how many packets per second are flowing. You may also be under a ping attack from the outside to see what ports are open on your machines. I've had to turn off ICMP completely because with a /23 (512 ips) I get hammered by these script kiddies - same symptom - 1 second + pings - it's the router saying "no response from 1.2.3.201" "no response from 1.2.3.202" "no response from 1.2.3.203" over and over again. If it's over your limit from your upstream ISP - that would explain the severe latency. Most throttling systems add massive latency to bring you within your "bought and paid for" bandwidth. I don't think it's the microwave net - sounds like a person running file sharing software or the like. But I could be wrong. Your logs on the bridges will tell you if they are getting interferance - I just doubt it. This type of limiting was put in place after cable got a bad rap for slowing down when one pig would do a 6 Mbps download, and all his neighbors got 300 baud connections suddenly (i'm exagerating) - so they "capped" the lines via latency which still delivers they payload, just not as fast. Ethereal will get to the bottom of it. Blocking icmp was my solution to these bastards killing my line (They must have been colo'ed in a ds3 room - I had a tiny T1 - when the attacks came it was 1.544 up 1.544 down - jam packed. No room for my data at all. Everett. If you want more info - send me the details of your link privately. > > I run a neighborhood WISP and my WAP uses a Soekris board with a Senao > 2511CDPLUS EXT2. > > Recently a couple of my clients have been experiencing timeout problems > to the extent that they can't use my service. I've been logging pings > from the WAP to their WET11's and most of the time they return normal > pings. But every few minutes the ping times go up to several seconds, > then return to normal again. For example... > > Sat Nov 15 20:17:02 PST 2003 > 93 dBm > 64 bytes from 192.168.168.70: icmp_seq=0 ttl=64 time=13.6 ms > 64 bytes from 192.168.168.70: icmp_seq=3 ttl=64 time=11.4 ms > Sat Nov 15 20:18:02 PST 2003 > 93 dBm > 64 bytes from 192.168.168.70: icmp_seq=0 ttl=64 time=10113.4 ms > 64 bytes from 192.168.168.70: icmp_seq=3 ttl=64 time=7180.8 ms > Sat Nov 15 20:19:01 PST 2003 > 93 dBm > 64 bytes from 192.168.168.70: icmp_seq=0 ttl=64 time=23.7 ms > 64 bytes from 192.168.168.70: icmp_seq=3 ttl=64 time=5.4 ms > > The clients have consistently strong radio signals (90+ dBm) - only the > IP is erratic. When I use my laptop (with D-Link card) at the client > location it works fine. > > I've tried several things like swapping out the WET11 client, turning > packet shaper off, changing max speed. These haven't helped. Could > this problem be due to interference or...? I'd really appreciate any > ideas. > > Alan in San Jose > > __________________________________ > Do you Yahoo!? > Protect your identity with Yahoo! Mail AddressGuard > http://antispam.yahoo.com/whatsnewfree > -- > general wireless list, a bawug thing <http://www.bawug.org/> > [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless > -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
