At home i have a number of PCs that can connect to my network.


The motarola Cable Modem,Linksys SPA2102 Voip Adaptor and DLink DI714P+ are each on their own subnet and are each running DHCP.

The end result is that i seem to have alot of packet loss and poor network speeds.

Could their be excessive network overhead? Im only running basic WEP security and MAC filtering.

Thanks in advance.

GLO

I'd dump the DHCP and just use a static address scheme. It's not that large of a network that it can't easily be managed.

I don't see how DHCP would cause packet loss. As soon as a device has recieved an address via DHCP it doesn't echange anymore data w/ the DHCP server until it is either reset and needs to re-acquire another address or the DHCP lease runs out and must be renewed. Even though it's very unlikely that DHCP is causing this setting up a static network would fix this.

As for the layout of your network. You shouldn't require multiple subnets with as few computers as it seems you have. Yes they can be beneficial, but there is no significant benefit that I can see in this case. I used to run a VOIP box (Linksys PAP2), 2 wireless routers (WDS setup to cover our apartment and outside of our apartment), and about a 10 computers (including 2 laptops on wifi) all on the same subnet. The only major thing subneting would do on such a small scale is limit multicast traffic, which is already practically zero on such a small network. I also ran WPA-TKIP and MAC filtering on the wifi points with no ill effects.

Next, does the packet loss occur on all the computers, just the wireless clients, etc.? If only the wifi clients are getting packet loss then I'd suspect a (possibly) faulty access point/wireless router. If only the clients connected to the network via the repeater AP are having problems then that's pretty self explanatory what the problem is. If all the systems are having packet loss I'd once again suspect a faulty AP/wireless router. See if it happens with a replacement router if possible?

Now, for the junky speed question. According to a download of the users guide for the Dlink DI-714P+ router shows that this is a 802.11b router. The fastest transfer it supports is 22Mbps via a D-Link Airplus network card. It will operate at 11Mbps with standard 802.11b (Wireless B) network cards. Now....11Mbps over wireless is considered poop these days.

At maximum reception (standing right next to the AP) this is what your transfer speeds break down to. You get 11Mbps to play with. The acknoledgement traffic (the signals that both the wireless transmitter and receiver send saying that the data was retrieved successfully) eats up 1/2 of the bandwidth. This leaves us at 5.5Mbps. Now the TCP/IP protocol does that same thing (sending a message back and forth from host to host saying the traffic was received successfully). This leaves us at 2.75Mbps max bandwidth. That's roughly 343KB/s MAXIMUM throughput. Keep in mind this is if you are immediately next to the AP. This figure drops exponentially as you get farther and farther away from the AP.

That is what is affecting your "poor network speeds." You just don't have the speed to begin with. Another factor is that aside from already have poor wireless max bandwidth it appears you've got piles of clients on that thing. This does nothing more than make that already swamped and slow AP that much more slower. Because of the fact that the router is just swamped to begin with it could end up getting overworked and actually drop packets because it can't handle all the data. This could be what is causing your packet loss.

My honest suggestion. Spend a few dollars and invest in at least a Wireless G Router. I had a few $$ to spend so I've got a D-Link Gamerlounge 4300 (DGL-4300) and it holds up quite nice to multiple wireless clients. If you've got the money, shell out for nice new Pre-N MIMO router. Yeah your clients can't use the awesome ability of the Pre-N technology but you'll get several good side effects regardless.

1) MIMO routers are inherentely better when it comes to signal range. Multiple antennas give much better coverage area. Unless those few clients using the repeater AP are football fields away a MIMO router will probably render that repeater AP unneeded.

2) Having a Pre-N router will give you the ability to serve clients that do have Pre-N capability or could be easily upgraded (by means of new PCI card or whatever).

3) Even if your clients aren't Pre-N capable if they have at least Wireless G chances are they will see a small if not noticable speed difference. Why? MIMO APs/routers are capable of giving consistently near maximum throughput even at far distances. Standard APs/routers loose throughput as the client gets further and further away.

Sorry it's so long but I hope this has been a bit helpful. ~ Crash_Maxed

Quote: Originally Posted by crash_maxed Sorry it's so long but I hope this has been a bit helpful. ~ Crash_Maxed

It may be long but its definitely not long winded. Yes, it is helpful!

Quote: Originally Posted by crash_maxed I don't see how DHCP would cause packet loss. As soon as a device has recieved an address via DHCP it doesn't echange anymore data w/ the DHCP server until it is either reset and needs to re-acquire another address or the DHCP lease runs out and must be renewed. Even though it's very unlikely that DHCP is causing this setting up a static network would fix this.

I agree.

Quote: Originally Posted by crash_maxed As for the layout of your network. You shouldn't require multiple subnets with as few computers as it seems you have. Yes they can be beneficial, but there is no significant benefit that I can see in this case. I used to run a VOIP box (Linksys PAP2), 2 wireless routers (WDS setup to cover our apartment and outside of our apartment), and about a 10 computers (including 2 laptops on wifi) all on the same subnet. The only major thing subneting would do on such a small scale is limit multicast traffic, which is already practically zero on such a small network. I also ran WPA-TKIP and MAC filtering on the wifi points with no ill effects.

I realise that i can run them all on the same subnet, and thats what the plan is to do via the DI-714P+. I do use MAC filtering and basic WEP security (a limit of the 714P+)

Quote: Originally Posted by crash_maxed Next, does the packet loss occur on all the computers, just the wireless clients, etc.? If only the wifi clients are getting packet loss then I'd suspect a (possibly) faulty access point/wireless router. If only the clients connected to the network via the repeater AP are having problems then that's pretty self explanatory what the problem is. If all the systems are having packet loss I'd once again suspect a faulty AP/wireless router. See if it happens with a replacement router if possible?

packet loss is experience throughout the network. Here are the wireless stats from the wireless Cable Modem SBG900

WIRELESS STATISTICS
		Transmitted Fragment Count			476335
		Multicast Transmitted Fragment Count			48426
		Failed Count			0
		Retry Count			37684
		Multiple Retry Count			20551
		Frame Duplicate Count			2963
		Request to Send Success Count			0
		Request to Send Failure Count			0
		Acknowledge Failed Count			126456
		Received Fragment Count			0
		Multicast Received Fragment Count			7022758
		Frame Check Sequence Error Count			4513504
		Transmitted Frame Count			476335
		WEP Undecryptable Count			8

Fact is you have multiple DHCP servers trying to hand out data to the machines connected to them... cluttering the network... Example: If I send 1000 unsorted mails to the post office and instead of use out of town slots and parcel slots just shove them all into one it would slow them down sorting it all out...... you should disable the DHCP on all but one device.... Set them all to the same subnet, and give them each (all but the main with DHCP) a unique device IP (sometimes they have the same IP but that will generally make your network, nowork.... anyway... hope this morning post made sence.. I just work up and am sick as hell... News postin' time...

over 7 million multicast fragments???? what the???? Shouldn't be that much multicast traffic. Nonetheless thats an insanely high fragment count. Does the count keep on growing (really fast that is) as you refresh the statistics page? If it does you should try taking systems offline till you find the culprit that is multicasting that much s***.

Quote: Originally Posted by Twizted you should disable the DHCP on all but one device

Given the implications of subnets he must either static his devices on a per subnet basis or run a DHCP server in EACH AND EVERY subnet. Unless he destroys the subnet setup. If he unifies everything onto one subnet then he only needs one.

Quote: Originally Posted by crash_maxed Now, for the junky speed question. According to a download of the users guide for the Dlink DI-714P+ router shows that this is a 802.11b router. The fastest transfer it supports is 22Mbps via a D-Link Airplus network card. It will operate at 11Mbps with standard 802.11b (Wireless B) network cards. Now....11Mbps over wireless is considered poop these days.

I know but the traffic is 98% internet (so a 10M link will do the job) although i would like to start file sharing amongst the network, including MP3 and video streaming across the wifi netowrk.

Quote: Originally Posted by crash_maxed At maximum reception (standing right next to the AP) this is what your transfer speeds break down to. You get 11Mbps to play with. The acknoledgement traffic (the signals that both the wireless transmitter and receiver send saying that the data was retrieved successfully) eats up 1/2 of the bandwidth. This leaves us at 5.5Mbps. Now the TCP/IP protocol does that same thing (sending a message back and forth from host to host saying the traffic was received successfully). This leaves us at 2.75Mbps max bandwidth. That's roughly 343KB/s MAXIMUM throughput. Keep in mind this is if you are immediately next to the AP. This figure drops exponentially as you get farther and farther away from the AP.

Thats about right! But that is why i got the DWL2100AP to act as a repeater.

Quote: Originally Posted by crash_maxed That is what is affecting your "poor network speeds." You just don't have the speed to begin with. Another factor is that aside from already have poor wireless max bandwidth it appears you've got piles of clients on that thing. This does nothing more than make that already swamped and slow AP that much more slower. Because of the fact that the router is just swamped to begin with it could end up getting overworked and actually drop packets because it can't handle all the data. This could be what is causing your packet loss.

I guess the manufacturers never indicate how many concurrent wireless connections their equipement can sustain,

Quote: Originally Posted by crash_maxed My honest suggestion. Spend a few dollars and invest in at least a Wireless G Router. I had a few $$ to spend so I've got a D-Link Gamerlounge 4300 (DGL-4300) and it holds up quite nice to multiple wireless clients. If you've got the money, shell out for nice new Pre-N MIMO router. Yeah your clients can't use the awesome ability of the Pre-N technology but you'll get several good side effects regardless. 1) MIMO routers are inherentely better when it comes to signal range. Multiple antennas give much better coverage area. Unless those few clients using the repeater AP are football fields away a MIMO router will probably render that repeater AP unneeded. 2) Having a Pre-N router will give you the ability to serve clients that do have Pre-N capability or could be easily upgraded (by means of new PCI card or whatever). 3) Even if your clients aren't Pre-N capable if they have at least Wireless G chances are they will see a small if not noticable speed difference. Why? MIMO APs/routers are capable of giving consistently near maximum throughput even at far distances. Standard APs/routers loose throughput as the client gets further and further away.Crash_Maxed

The Motorola Wireless Cable Modem is infact a Wireless G AP. but im reluctant to hang all the clients off it because it is likely to destroy any VOIP call quality due to the data being access before the Linksys SPA2102 can prioritise the VOIP data.

The only solution i can see here is to try a Broadcom based wireless router wiht DD-WRT such as the Buffalo WRT-HP-54G Hi Powered wifi router or the Asus WL-500G Premium (not sure if DD-WRT will disable the USB port and torrent downloading) or the Mitusbishi Digital R100 (base version of the Asus WL500G) or the popular Linksys WRT54G units.

I know that with one of these units i can prioritise according to Mac address/ IP and as such the Voip adaptor wont need to be between the modem and the wifi router.

What are your thoughts now?

Quote: Originally Posted by GLO The Motorola Wireless Cable Modem is infact a Wireless G AP. but im reluctant to hang all the clients off it because it is likely to destroy any VOIP call quality due to the data being access before the Linksys SPA2102 can prioritise the VOIP data.

Ahhh...didn't realize the cable box was an AP. As far as the reluctant to put all clients on it thing. Since you don't have any QoS (quality of service..the thing that can prioritze connections) running it won't matter where you hang them. If a client is saturating your internet connection it won't matter if he's hung off of the cable box or downstream off of the DI-714. Placement on the network is more or less irrelevant. Someone sucking up the entire connection can do it regardless of which piece of equipment he is connected to. Even if a call comes in via VOIP there will be no allotment of bandwidth to the VOIP box "just because it's has closer access to the cable box". Without QoS a client is a client. One client asking for a lot of bandwidth is likely to bully all the other devices out of their bandwidth, regardless of how little they are asking for.

Quote: Originally Posted by GLO The only solution i can see here is to try a Broadcom based wireless router wiht DD-WRT such as the Buffalo WRT-HP-54G Hi Powered wifi router or the Asus WL-500G Premium (not sure if DD-WRT will disable the USB port and torrent downloading) or the Mitusbishi Digital R100 (base version of the Asus WL500G) or the popular Linksys WRT54G units.

This is a possible solution as DD-WRT does support QoS. However, be forwarned that any piece of equipment running QoS will literally grind to a screeching halt if you start running torrents. QoS was never designed to handle the dozens upon dozens of connections that torrent based applications require. My router supports QoS, but because I do use torrents every so often I have disabled it as even this $120 gaming router can't handle it. Why does this happen? Torrents send out dozens of requests to peers that are found via the tracker that the torrent is currently using. QoS works by handing out bandwidth on a per connection basis by applying a list of rules that you, the user, set. Problem is that consumer routers just aren't powerful enough and can't keep up with comparing and applying these rules to dozens of connections.

Next up, althrough the WRT54G WAS (please note the capital "WAS") a great router I urge you to stay away from this monster. With the advent of revision 5 these routers no longer use the awesome 4Mb flash rom they used to. Instead they now use a tiny 2Mb flash rom and a crappy base OS called VxWorks. You CAN flash DD-WRT over this, but it does not perform well. Trust me, I had two of them. Why had? They both fried after 2 months. I had its ancestor (a version 3) run for 2 solid years). Either go for one of the other routers you listed (the ASUS or the Buffalo) or try the WRT54G's big brother, the WRT54GL....it runs on the good ol' linux kernel the old ones (revision 4 and lower) used ot use. Not to mention it's the bigger 4Mb flash rom...so full sized DD-WRT (full sized meaning NON-feature limited) will fit on it too.

Lastly....if you do get one that is capable of flashing to DD-WRT. I recommend looking at another firmware fork called HyperWRT + thibor15c. I used to run it on my old v3 WRT54G. That firmware had a lot more features than DD-WRT ever did. One of the coolest was "AP bridging" You could have the AP connect to another AP (supported no encryption as well as WEP...in case it was a friends AP) as a client and transparently bridge the ethernet ports on the router. Thus it would transparently bridge your LAN (or just one computer) onto the target APs entire network ^_^. I used this extensively during LANs to bridge to an AP on the other side of the building, so we could be secluded in our own room