Internet Tweak will automatically detect whether you are using Windows 2000/XP//Me/98/95 operating system, and only the correct DUN (Dial-Up Networking) Performance tab can be activated (one of the tabs with telephone icon). The options that you can set are:
Change Maximum Transmission Unit (MaxMTU) for Windows 95 Information is transferred across the Internet as packets. Windows 95 default has a MaxMTU of 1500, it means that packets of 1500 bytes are sent every time. This 1500 bytes is actually the default for an Ethernet network (LAN) and not for the Internet (dial up networking/modems). Many routers used by ISPs have smaller value, e.g. 576, 512, or other values. If your ISP use 576, that means your 1500 byte packet is fragmented in 3 packets. With this fragmentation the overall speed goes down because it generates a lot of useless space (at the third packet). You can set the MaxMTU for Windows 95 to a value that gives the best out of your connection. Microsoft is recommending an MTU of 576 for connections under 128kbs, that's has been found to work well on many systems. The lowest setting should be 552, some terminal servers work well with 1002.
The MaxMTU value is actually limited by your ISP's MTU value, since all packets will be traveling through their servers. To determine the MTU of your ISP, try the following:
Open an MS DOS window and type
ping -f -l [packetsize] [www.yourisp.com]
[packetsize] is the amount of data you want to send (between 0 and 1500) [www.yourisp.com] is your ISP's URL
The largest [packetsize] that does not give you the error "Packet needs to be fragmented, but DF set" will be your ISP's MTU - 28 (the IP [20 bytes] and ICMP [8 bytes] header).
For example, if the largest [packetsize] is 1472, the your ISP's MTU is 1472+28=1500
Change IPMTU for Windows 98/Me Use this option to change the IPMTU (Internet Protocol MTU) setting for Windows 98/Me user. This setting has the same impact as change the MaxMTU for Windows 95 as described above.
Change MTU for Windows 2000/XP Use this option to change the MTU setting for Windows 2000/XP user. Note: Windows 2000/XP will use a default value of 576 if your connection speed is less than 128k and if over 128k it will use 1500. Change on this setting has the same impact as change the MaxMTU for Windows 95 as described above.
Maximum Segment Size (MSS) MSS or Maximum Segment Size, is the largest segment of TCP data that the Winsock is prepared to receive on a particular connection. If the MSS is too low, the data/header ratio will be low. And if the MSS is too high, the packets will tend to fragment if other networks have small MTU's. Performance can increase at times by reducing the MSS value. Internet Tweak has automatically set the MSS value to MTU-40.
Receive Window (RWIN)
RWIN determines how much data the receiving computer is prepared to receive. If the RWIN is too high, then this will result in greater data loss if the packet is lost or damaged in transit. If the RWIN is too low, then this will produce very poor throughput. As a standard, an RWIN value should be set 4 times the size of the Maximum Segment Size (MSS). You can try other settings, maybe 6x or 8x, to find the best possible RWIN value, especially when downloading large files or accessing web site with a lot of graphics.
Session Time To Live (TTL) The Time To Live value is included in the header of a packet, and is used to determine how long the packet should 'live' before it giving up and deciding that the destination web site does not exist. The default value in Windows Me/9X is 32 and and for Windows NT 4.0/2000/XP it is 128. But since the Internet continues to grow, it may be necessary to increase this value in order to reach every computer.
MTU Auto Discovery Setting this option causes TCP to discover the Maximum MTU (largest packet size) over the path to the destination site. By discovering the Path MTU and limiting the packets to this size, TCP can eliminate fragmentation at routers along the path with different MTU's. You can try to check or uncheck this option, to find out the best result.
Black Hole Detect Setting this option will enable TCP to try to detect Black Hole routers while doing MTU auto discovery. This is also increase the maximum number of retransmissions performed for a given segment, and therefore may decrease overall performance. You can try to check or uncheck this option, to find out the best result.
More NDICache Try to check this option to increase the Windows default NDICacheSize from 0 to an optimum value (16). This setting is for Windows Me/9X only.
Boost Modem Transfer Speed This setting affects the time (in milliseconds) the Operating System processes a COM port interrupt. Default setting is 2, recommended setting is 1.
Disable SlowNet Parameter You can try to disable slownet parameter for dial-up connections, to reduce timeouts. This setting is for Windows Me/98 only, and won't increase the performance significantly.
Session Keep Alive Specifies how often to send session keep-alive packets on active sessions. The minimum is one minute, the default is one hour in Windows Me/9X and two hours in Windows 2000/XP. Recommended setting is 10 minutes. It should be used when your ISP frequently disconnects you during short idle periods, such as a pause in web surfing to read the content of an interesting site.
Speed Up Internet Searches When you go to a web site, the first thing that happens is that a query goes out to the DNS server for IP address of the web site. In order to eliminate this query, you can simply add the IP address and web name into the HOSTS file in the Windows directory.
To find the IP address, just open the MS DOS prompt, type PING the web name (for example: ping www.microsoft.com) So, to visit Microsoft site faster, you can type the following in the Speed Up Internet Search option:
Press OK and Internet Tweak will insert it into the HOSTS file. You can do this for all the sites you regularly visit. For more description and sample, you can open the hosts.sam file inside Windows directory.