improve network speed

Hello...

Need to know more about your network to give a more specific answer. Here is some general advice:

BACKGROUND

- Ethernet is a "colission-based" networking scheme. All PCs share the physical network and use it freely but only one can do so at a time. When two try to do so simultaneously, both attempts fail. This is called a "colission". They both retry after the failure a random interval later.

- When there are a lot of active systems on a single network, the number of colissions increases and the effective network throughput drops dramatically.

- Colissions are reduced when you segment your network using switches or routers. Segmentation isolates your network into separate pieces that do not intercommunicate unless then have to.

- Bridges connect two network segments but do not help with colissions. All network traffic on both sides of the bridge is routed to the other side.

- The greater the amount of traffic a network segment has, the higher speed it must run at in order to maintain good performance.

- When a network has both 10 Mbps and 100 Mbps nodes, the network effectively runs at 10 Mbps when the 10 Mbps nodes are operating on it. Those 10 Mbps transmissions take 10 times as long to complete as the 100 Mbps ones do.

SUGGESTIONS

- Upgrade all nodes to 100 Mbps.

- Segment your network using switches or routers. Each segment should be 20 to 30 nodes maximum. Your needs may vary depending on traffic.

- Upgrade to 1000 Mbps for segments that all nodes share.

-----Steve Jackson

CEO/CSA
Software Corporation (Softcorp)
http://www.softcorp.us/probono
Advanced pro bono tools and utilities free for personal use

Switched or Hub?? Most likely you have your servers linked with a 100mbs pipe, and trying to push all data from your switch/hub to 1 or 2 servers over 100mbs is DEADLY.. upgrade those to 1000mbs ... remember that your network is only as fast as its slowest component...

In addition, make sure that if the switch ports are set to AUTO, the network cards are set to AUTO as well. I recently had to change a few.

Try review your network topology and equipements, is it time to upgrade? Upgrading from 10Mbps to 100Mbps or higher are feasible because it will eliminate most of the bottle-neck. Another side advantages is 100Mbps is far more easy to get a similiar replacement nowadays comparing 10Mbps device in case of hardware failure.
You might want to make sure there is no malwares, worms or someone are "abusing" the traffic.

A 10Mb switch will in general outperform a 100Mb hub. 100 computers doesnt sound like a lot. But if they are all connected via hubs there is a lot of wasted effort in the traffic. Worms, viruses, DOS attacks certainly could create a problem. Music sharing could eat it up too. If somebody is using their PC for a juke box for the rest of the network you could have trouble. I have to wonder what kind of data is going through the network.

The network has 2 10mbs hubs and 7 100mbs switches

in nowadays networks speed is the crucial thing and why we network administrators are there to eleminate and understand whats going on with our small or big network environment.this is our responsibility. if we cannot find the righ answers then we can get an help from specialized networking companies.as i told you follow these tips :

1* first chack your servers network cards.in nowadays servers the NICs must be 1gbps.

2* remove any HUBs if you are using in your network.todays networks HUBs are not a good idea.

3* chack your switches. they must support 1gbps connection speed or at least 100mbps.

4* using 10mbps and 100mbps NICs in computers together brings your network down ad makes it very slow.change 10mbps NICs with at least 100mbps ones.

5* verify that your backbone cabling (between switches) must be CAT6 standart cables.CAT5e is also enough but CAT6 cabling is crucial.

6* verify that your cabling from switches to your client PCs are CAT5e class cables.

7* you must find where your cables run from.if they are too close to heavy electrical machineries , light resources like flueresant lights move your cabling from that kind of cross talk creating sources. or in this kind of areas use at least STP class CAT5e cables. STP cables are better than UTP cabling.

8* if you are using WLAN (WirelessLAN) Than make sure that all client laptops and computers in your network must have 802.11g network card in them and there are not any 802.11b network cards connecting to your WLAN Access Points at the same time. this stuation also brigs your WLAN down and makes it very slow.

9* for your wireless lan again check that all the wireless access points are in different channels (1*6*11 rule)and their positioning are high enough and their antennas are vertical.

10* for wireless lan check that there are not any cordless phones which works in 2.4ghz band and no microwave ovens,thick walls,heavy iron consutruction in the area,and no wiring in your glasses that you use in the room doors.

I hope these tips helps you well.