I just tcpdump'd a DNS request for google.com. The request (the one that would be affected by RTS/CTS) was 32 bytes. The reply was 220 bytes. So I maintain that you'd have to have the RTS/CTS threshold less than 32 + IP header size. If a wireless network is having contention problems with 50 byte packets, RTS/CTS isn't going to help. But I think we've wandered OT.
-Kristian On Thu, 2010-08-26 at 10:07 -0700, Ryan Spott wrote: > You have to set it to >512 for DNS. > > Remember that DNS is UDP so if the packets go away because the > wireless medium you are using is lossy then there are no more > re-transmits. Setting the RTS/CTS to just at the size of a UDP DNS > packet creates a virtual TCP-like network for those sized packets. > > ryan > > On Thu, Aug 26, 2010 at 9:42 AM, Kristian Hoffmann <[email protected]> > wrote: > > An RTS/CTS setting of 3000 means it's effectively disabled. You'd have > > to set it below 1500 for it to do anything. It's not looking like > > that's your problem anyway. RTS/CTS will help performance when > > customers upload large frames (specifically ones larger than your > > RTS/CTS setting). You'd have to set it to <100 for it to affect > > DNS/ARP/ICMP packets, and that would likely be a really really bad idea. > > > > My money is on too many layers of MAC NAT. Tranzeo and UBNT stations do > > it regardless, and MikroTik's do it with station-pseudobridge set. Do > > you know how many MAC NAT'd stations you have changed together? If > > there are multiple hops, switching intermediate ones to WDS should > > help/resolve the problem. > > > > > > -Kristian > > > > On Thu, 2010-08-26 at 09:15 -0600, Mark Dueck wrote: > >> I have about 25 clients on this AP. I think only 2 of them are NS2's, > >> the rest are SL2's and they are all updated to 5.0.4 firmware, which has > >> the fix for the limited connections that the 4.x firmware had. > >> > >> All the Tranzeo's have their RTS at 3000, their default. I checked the > >> NS2's, but I can't find that setting in the webGUI. How do I > >> check/change that? > >> > >> On 08/26/2010 07:56 AM, Ryan Spott wrote: > >> > Hey Mark, > >> > > >> > How many CPE are attached to your AP? > >> > > >> > Have you adjusted RTS/CTS Settings? Take a look here: > >> > > >> > http://www.tranzeofaq.com/RTS-CTS.html > >> > > >> > ryan > >> > > >> > On Wed, Aug 25, 2010 at 9:09 PM, Mark Dueck <[email protected]> wrote: > >> > > >> >> I don't think it's a DNS because most clients that are complaining are > >> >> from > >> >> one AP. Today I got one that's from a diff AP that said their net was > >> >> intermittent. > >> >> > >> >> I myself am browsing on the same network and never experience that > >> >> problem. > >> >> I have the same settings. > >> >> > >> >> Mostly Tranzeo SL2's as clients, with 2 PowerStations as AP's. The > >> >> rest of > >> >> the AP's are all Tranzeo. All clients are routed internally, but after > >> >> the > >> >> client radio everything is bridged. I rebooted the gateway to clear > >> >> the arp > >> >> cache, but clients are still experiencing the same problem. > >> >> > >> >> Could it cause a problem with the fact that the gateway is multiwan and > >> >> 2 of > >> >> it's wan's are on the same network as the clients, but different > >> >> subnet. I > >> >> know I need to VLAN, but had some issues with VLAN not connecting. > >> >> > >> >> > >> >> On 08/25/2010 05:51 PM, Josh Luthman wrote: > >> >> > >> >> What kind of radios? > >> >> > >> >> You sure it isn't a problem with the DNS servers? > >> >> > >> >> On Aug 25, 2010 7:44 PM, "Mark Dueck" <[email protected]> wrote: > >> >> > >> >> Hi, > >> >> > >> >> I've got some issues on my network with clients complaining they have no > >> >> internet. When I come around, as soon as I ping gateway and then google > >> >> dns, the browsing is back up. I showed a client how to do this, and he > >> >> says whenever his internet goes down, as soon as he pings it's right > >> >> back up. > >> >> > >> >> Anyone have ideas why this could happen? > >> >> > >> >> Thanks, > >> >> Mark > >> >> > >> >> > >> >> -------------------------------------------------------------------------------- > >> >> WISPA Wants You! Join today! > >> >> http://signup.wispa.org/ > >> >> -------------------------------------------------------------------------------- > >> >> > >> >> WISPA Wireless List: [email protected] > >> >> > >> >> Subscribe/Unsubscribe: > >> >> http://lists.wispa.org/mailman/listinfo/wireless > >> >> > >> >> Archives: http://lists.wispa.org/pipermail/wireless/ > >> >> > >> >> > >> >> > >> >> -------------------------------------------------------------------------------- > >> >> WISPA Wants You! 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