I have been having trouble with my router dropping connections, the Linksys(Never buy linksys, all i've had is trouble) tech told me to set the MTU, which was disabled, to 1500. How would this solve the connection being dropped often(it works right away after, so it does not effect browsing)? So please what is this MTU thing? as detailed as possible please, I can't find information anywhere.

MTU = Maximum transmission unit . Basically the maximum size of a packet that can be transmitted .

So what is the MTU if it is turned off? When disabled i assume there is no max, so how would this solve the connection being dropped on 5 different machines? Thanks for all the information, im slowly starting to understand

It's always on, it's part of the TCP/IP process.. I found lot's about MTU.. http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci213605,00.html

I have had no trouble finding out all kinds of information about MTU (Maximum Transmission Unit) size. The TCP/IP setting for MTU in Windows can not be "turned off". Kind of like turning off the memory size of a processor. However, its default size depends on the version of Windows and the communications protocol selected. In older versions, when you establish a Dial-up configuration with no LAN support the default MTU value is 576 bytes. If you enable TCP/IP lan support, the default is 1500. However, if you have Windows XP and use its WinXP PPPoE instead of some other PPPoE login, it's default value is 1480 and can not be set higher. Of course the MTU value is just the maximum size packet that TCP/IP will try to use, and you can set it a lot higher but that will not work with most networks too well. If any device or router in a network is set to a smaller MTU size, then larger packets will either get rejected and dropped or broken up into smaller packets, depending on how the routers are set. For example AOL's network is designed around a MTU size of 1400 bytes, but is does not drop larger packets, it just breaks them in to two separate packets, which slow the through put. TCP/IP provides for a Path MTU Discovery option which is enabled by default in newer versions of Windows TCP/IP support, but is not supported by all network routers, to avoid this problem. This way a Client can ask the Host and all routers in between what their MTU size is, and adjust what it sends. If you have disabled this Path MTU Discovery TCP/IP setting and send large packets, some networks and hosts will disconnect you due to the errors that can occur, or the dropped packets. On slower links, an Internet router might want smaller packets, or if designed to support Dial-up. Even the great low cost LinkSys routers have an option to limit MTU size of packets passing through them. The Disabled default size in Linksys routers is 1500, or the maximum used. There is an option to Enable a smaller MTU and only allow that maximum to go out on the Internet. You would only use that option if you were going through something like AOL's network, yet you have a local network using Ethernet and you want it to use an MTU of 1500 for local network transfer. This way the Linksys router would respond to a Path MTU Discovery request with 1400 and the Client TCP/IP handler would know to only send a maximum 1400 byte packet size, instead of 1500, when going through the router to the Internet. It this feature is disabled, then the router does not respond to the request and just passes the packet requests. So if you have setup a local network using 1500 byte or larger packets, and have enabled the router MTU setting and set a larger value than the ISP likes, then packets passing out to the WAN might be larger than some parts of the Internet can handle and this can cause dropped connections, often at random. Normally you want to set all systems MTU at 1500 if using an Ethernet connection and leave the Linksys routers MTU setting disabled, so that it does not get involved. But if your ISP is AOL or one of their business partners, you want to Enable the Linksys router MTU setting and use 1400, or what ever the ISP supports. In the special case where your ISP is a Dial-up network and you have a dialup modem that the router is connecting to the WAN through, then you would want to enable the router MTU and set it to 576. The drawback of having to set a router MTU smaller than 1500 is that it decreases the throughput of the local network traffic that passes through the router. To get around this, you have to use switches that support your local network's MTU size and configure it so local traffic does not go through the Linksys router with WAN connection. Some local networks can be set up to use a much larger MTU for local traffic, as high as 65k, to increase throughput, don't us Path MTU Discovery, and of course have problems as soon as they try to connect up to the WAN.

It all makes sense now, and my connection has stopped dropping. Someone said "you can't turn off MTU" I ment that the option on my linksys router had it disbaled. 1500 has worked fine for everything, and this is a huge relief. Thank you for all your time, especially the last post, I really hope that was copied and pasted, if not, wow.