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I have integrated two networks, token ring to Ethernet and then back to token ring. The flow of the data is as follows: MADGE switch (token ring) - OMNI switch (Ethernet) - gigabyte fibre line - OMNI switch (Ethernet) - Deskstream switch (token ring). All workstations have token ring adapter cards installed by default with maximum frame size set to 4096k. On initializing a NetBEUI based application over the above network configuration, the application dies. But on manually lowering the default maximum frame size to 1500k, the application works flawlessly. It seems that the frame sizes in Windows 95 do not negotiate downward frame sizes. The switches are bridging the data, and I faced no problems with Windows NT based workstations. Are there any Windows 95 patches to resolve this problem? Kindly suggest.

Different Network Interface Cards (NICs) support different maximum packet sizes, depending upon the media (Ethernet, Token Ring). Some of the applications do not know what the media is. The "default" sizes can cause problems here.

Either the WinSock network API, the IPX/SPX stack, or the network adapter driver must break the application message buffers into a suitable packet size for the given media. Maximum packet sizes are also dependent upon NICs. This is a Vender Protocol Stack issue, not an issue within application.

To resolve the problem please visit the following link to download the patch (olitokol.exe) for your Madge NIC: http://support.microsoft.com/ support/kb/articles/q135/3/14.asp

I am using a laptop along with a desktop. In case the laptop hard disk crashes, I want to restore the backed up data (on the desktop) to the laptop through PCMCIA card driver. Usually I boot the laptop with the bootable floppies and get the data on desktop. Is there any way to recognize PCMCIA card in DOS. That is, is it possible to assign some drive letter to PCMCIA card while the system boots from a bootable floppy drive.

Most PCMCIA card manufacturers provide DOS drivers/software which will enable the PCMCIA card to work under DOS.

The following suggestion might help you find a solution for the problem you are facing:

1. Networking the Laptop and the Desktop.

2. Using an external Zip Drive/CD Writer.

I want configure IBM Home & Away Credit card Adapter for LAN (14.4 Modem + Ethernet LAN) but have been unsuccessful in doing so on my IBM Thinkpad 365X Laptop, in spite of using HAWIN95.EXE driver files from IBM. The modem gets installed correctly as Standard Modem and functions properly but the network part does not get installed correctly.

The HAWIN95.EXE drivers work with Windows 95. The problem you are facing could be due to incorrect or corrupted drivers that are not able to recognize the correct network card.

Follow these steps to solve the problem:

1. Go to Start - Settings - Control Panel and then double-click on System.

2. Click the Device Manager tab.

3. Click the "Network adaptors" branch to expand it, select the drivers.

4. Click on Remove.

5. Insert the driver CD/floppy into the CD-ROM/floppy drive and click on Refresh.

6. When prompted to "Specify the location for the driver", point to the driver file in the CD.

7. Click on Finish to complete the installation of

the drivers.

8. Restart the computer.

Note: Make sure that you provide correct network drivers for the Windows 98 operating system. You will have to contact your local hardware vendor for IBM Home & Away Credit card Adapter drivers for Windows 98.

We have a Compaq Prolaint Ml 370, 733MHZ, 128 MB RAM, having Windows NT 4 Server installed on it. We have 24 Port Switches of Dlink. All workstations are PIII 600 MHZ, 64 MB RAM, and have Windows 98/95 installed.

We are running DOS based application from the server. Sometimes the network slows down automatically and the user faces a problem running the applications thus making applications slow. Is something wrong with the network or do I need to upgrade the systems?

The primary symptom of Network Congestion is poor network performance within a segment of your network or across the entire network. This may occur only occasionally, during times of high usage.

The causes for this can be varied. You need a network monitor to determine the level of bandwidth being used across the network at the times of peak usage, and the types of packets being transmitted. A protocol analyzer can give you more information regarding the segments having the highest of traffic and any bottlenecks across the network.

Please check the following to optimize the speed of network access. And also make sure the distance is less than 150 meters from the server.

1) Check cable connections for any loose contacts.

2) Check whether the Network Interface Cards (NIC) are configured properly.

3) Check for high numbers of packets from one IP address. A malfunctioning

network adapter card could be "chattering" and sending lots of unnecessary packets.

4) Check to see whether any new applications have been installed on the network. There could be a possibility of a client/server application generating lots of packet traffic.

5) Network speed also depends on the number of users working currently. The

Network Congestion increases with an increase in the number of users on the network.

6) It is better to use Fiber Optic cable to increase the speed in a network.

The following could help to increase network access speeds from your clients:

1. First you may try to maximize throughput for application serving in Windows NT. Go to Start - Control panel and double click on the Network icon. Select the "Services" tab, Click on "Server" and click on "Properties" button. Choose "Maximize throughput for network applications" or choose "Balance".

2. Check whether the protocol binding order matches between server and clients.

3. Check for other bottlenecks in the performance of the Windows NT server (using performance monitor and Event viewer).

Please visit the following link for to learn more about this:

www.helmig.com/j_helmig/netslow.htm

It would be helpful, if you could provide some more details regarding your network configuration like :

1. Type of network topology implemented (STAR, BUS, RING).

2. Type of network cables used.

3. Distance between systems.

I have Windows 2000/ME (client machine). I am unable to connect to my RAS server-using dial up, it gives an error 619 port was disconnected but I am able to connect to the Internet thus ruling out the problem of modem connectivity. I am able to connect to RAS server on Windows 95/98 but not in the Windows 2000/ME (client machine). Kindly explain.

This issue occurs because the account you were logged on with at the time you joined the domain did not have administrator privileges on the Windows 2000 domain. Because of this the services that could easily compromise network security, such as RRAS and deny clients the ability to obtain access to the domain.

I would suggest that you follow these steps to solve the problem:

Firstly you must register the RRAS server in Active Directory using an account that has domain administrator permissions. To do so, use either of the following methods:

Add the RRAS Computer to the Appropriate Group

(NOTE: This method may be used with Windows 2000-based and Windows NT-based RRAS or RAS servers.)

Add the RRAS computer to the appropriate group:

Log on your Windows 2000-based computer with an account that has administrator privileges on the Windows 2000 domain.

Launch the Active Directory Users and Computers MMC snap-in and then double-click your domain name.

Double-click the Users folder, and then double-click the RAS and IAS Servers security group.

Select the members tab.

Add the RRAS server to this group.

Use the Netsh.exe Utility.

(NOTE: The Netsh.exe method can only be used if the RRAS server is Windows 2000-based.)

Use either of the following methods with the

Netsh.exe tool:

Method 1:

Log on the RRAS computer using an account that has domain administrator privileges, type Netsh RAS add, registered server at a command prompt, and then press ENTER.

Method 2:

To run a command with administrator privileges without being logged in as an administrator:

At a command prompt on the RRAS computer, type runas /user:domain name\administrator name "cmd", where domain name is the appropriate domain name, and administrator name is the appropriate administrator name. You are then prompted to enter a password for this account. If this computer is able to connect to the domain controller and verify the credentials, a command prompt opens with the following information in the title bar: cmd (running as domain name\administrator name).

At a command prompt, type Netsh RAS add registeredserver at a command prompt, and then press ENTER.

We need to connect two offices at a distance of 2 Km for voice & data communications. One of the offices is having 2 Mbps Internet VSNL leased line. Is it possible by some means for the other office to share the same lease lines? Is there any mean by which voice communications between two offices can be done through one circuit (both the offices have leased lines)?

To connect the LANs between two offices, you can connect using the Serial port available in your routers at the two offices. However, you cannot share the leased line from VSNL for LAN to LAN connection.

For laying the cables you will need to contact the DOT (Department of Telecommunications)

Please visit the following link for more details about

connecting remote office LANs: www.dcbnet.com/notes/9603l2l.html

I have two computers with Ethernet cards having RJ-45 connectors. I want to connect them using Cat-5 UTP cable for my Internet sharing without using a hub. I have heard that this is done by using a cross over UTP cable. Kindly tell me the details of this cable and how to set it.

For connecting two computers without a hub you need to use a cross over cable which has changes in the pin configurations, different from a UTP cable. To make the crossover" you must know how the pins are numbered on a jack and a plug and the difference between a jack and a plug. The jack is the female counterpart of the plug. Patch cables will have a plug at each end. A jack is a receptacle and a plug goes into the jack. The 8 pins in a RJ-45 jack are numbered 12345678 as you look at the cavity in the wall or on the baseboard. The 8 pins of a RJ-45 plug are numbered 87654321 as you look directly at the plug with the cable running away from you. You can use only pins numbered 1, 2, 3, and 6. To make the crossover you must connect pin 1 to pin 3 and pin 2 to pin 6. You will do this on only one end of the UTP cable. If you do it on both the ends it wouldn't be a crossover cable.

Please visit the following link for more information regarding making cross over cable and connecting the computers:

www.makeitsimple.com/how-to/dyi_crossover.htm

www.makeitsimple.com/how-to/simple.htm

Once back in Windows click Start - Settings - Control Panel. Double click on Network and install the following components.

To add these components, use the appropriate method:

Client for Microsoft Networks

1. Click Start - Setting, click Control Panel, and then double-click Networks.

2. On the Configuration tab, click Add.

3. Click Client, and then click Add.

4. In the Manufacturers box, click Microsoft. In the Network Clients box, click Client for Microsoft Networks, click OK.

File and Printer Sharing

1. Click Start - Setting, click Control Panel, and then double-click Networks.

2. Click Add - Service, and then click Add.

3. In the Manufacturers box, click Microsoft. In the Network Services box, click File and printer sharing for Microsoft Networks, and then click OK.

Protocol (NetBEUI and IPX/SPX protocols)

1. Click Start - Setting - Control Panel, and then double-click Networks.

2. Click Add - Protocol, and then click Add.

3. In the Manufacturers box, click Microsoft. In the Network Services box, click a protocol. Be sure that at least one protocol is installed on both computers.

Restart your computer when you are prompted to do so.

(NOTE: You might be prompted to insert the Windows CD to install certain components)

To Share Internet Connection

Internet Connection sharing technology provides home and small-business PC users who have networked computers the ability to share a single connection to the Internet. For a family with multiple PCs and other Internet devices, Internet connection sharing allows one person to send e-mail, another to play an online game and another to browse the Web.

Please visit the following links for more details on setting up "Internet

Connection Sharing (ICS)" and how to add clients in Windows 98:

http://support.microsoft.com/support/kb/articles/Q234/8/15.ASP

www.annoyances.org/win98/features/ics.html

What is the difference between Class A, B and C IP Addresses. Also, let me know how I can check the validity of a particular IP Address.

Since networks vary in size, there are four different address formats or classes to consider:

Class A addresses are for large networks with many devices.

Class B addresses are for medium-sized networks.

Class C addresses are for small networks (fewer than 256 devices).

Class D addresses are multicast addresses.

Summary of IP Address Classes

Class A:

0nnnnnnn hhhhhhhh hhhhhhhh hhhhhhhh

First bit 0; 7 network bits; 24 host bits

Initial byte: 0 - 127

126 Class As exist (0 and 127 are reserved)

16,777,214 hosts on each Class A

Class B:

10nnnnnn nnnnnnnn hhhhhhhh hhhhhhhh

First two bits 10; 14 network bits; 16 host bits

Initial byte: 128 - 191

16,384 Class Bs exist

65,532 hosts on each Class B

Class C:

110nnnnn nnnnnnnn nnnnnnnn hhhhhhhh

First three bits 110; 21 network bits; 8 host bits

Initial byte: 192 - 223

2,097,152 Class Cs exist

254 hosts on each Class C

Class D:

1110mmmm mmmmmmmm mmmmmmmm mmmmmmmm

First four bits 1110; 28 multicast address bits

Initial byte: 224 - 247

Class D addresses are multicast addresses

Class E:

1111rrrr rrrrrrrr rrrrrrrr rrrrrrrr

First four bits 1111; 28 reserved address bits

Initial byte: 248 - 255

Reserved for experimental use

An IP address has two parts: the identifier of a particular network on the Internet and an identifier of the particular device (which can be a server or a workstation) within that network. The IP address is usually expressed as four decimal numbers, each representing eight bits, separated by periods. This is sometimes known as the dot address and more technically, as dotted quad notation. For Class A IP addresses, the numbers would represent "network.local.local.local"; for a Class C IP address, they would represent "network.network.network.local".

In this way you can verify whether the IP address is valid or not.

I have set up a networking as per the guidelines in the magazine named PC Quest, May 2001 issue (page no.79 to 83), but am unable to access another PC in the Network Neighborhood on the computer.

There could be the possibility of the Microsoft Network components not installed properly.

Ensure that the following network components are installed in all the Windows clients:

I have two PCs running Windows 98 SE and Windows 2K Professional. Is there any way by which I can share an Internet connection (dialup) using DCC with a parallel cable.

Please perform the following to configure Direct Cable connection:

1. For the following steps to work properly you must already have or purchase a Null Modem Cable and must be connected directly to each of the computers you plan to connect to.

2. For Direct Cable connection to work you must first install the software used for the communication.

To install Direct Cable Connection, click Start - Settings - Control Panel. Double click on Add Remove Programs, select the Windows Setup tab, now double click the Communications icon and check the Direct Cable connection box. If this box is already installed it is recommended that you uncheck the box and then place the check back in the box to ensure that the complete program is installed on the computer. Once completely installed reboot the computer.

3. Once back in Windows click Start - Settings - Control Panel. Double click on Network and install the following components.

4. Double click My Computer; right click on the drive you wish to share your information on. (Usually this would be Drive C). Once the Properties window for the drive is open click the Sharing tab and choose the option for Shared As. Ensure a name is entered in Share Name. Click the Apply button and reboot the computer to ensure the changes have taken affect.

5. Once the above steps have been completed you must then decide which computer would be host and which computer would be the guest. Once this is determined, first setup the host computer by Clicking on Start - Programs - Accessories - Communications. Click on Direct Cable Connection. In the Direct Cable Connection box choose the option for Host, select the communications port that you wish to set this computer to. Click Next, your computer will then wait for the guest computer to send signal to the host computer.

6. Once the above steps have been completed, for the second computer in setting up and configuring the Direct Cable connection. Click Start - Programs - Accessories-Communications. Click on Direct Cable Connection. In the Direct Cable connection box choose the option for Guest; select the communications port that you wish to set this computer to. Click Next and the computer will start searching for the host computer.

Once the host and the guest have been setup you should establish a connection to be able to browse the hard drive that has been shared through Network neighborhood.

Now you can transfer the required files from you laptop on to your computer.

Please visit the following link for more details

about setting up direct cable connection: www.helmig.com/j_helmig/W2KDCC9X.HTM

I want to know more about using different types of IP addresses such as A class and B class on the same network

An IP address is an identifier for a computer or device on a TCP/IP network. Networks using the TCP/IP protocol route messages based on the IP address of the destination. The format of an IP address is a 32-bit numeric address written as four numbers separated by periods. Each number can be zero to 255. For example, 1.160.10.240 could be an IP address.

Within an isolated network, you can assign IP addresses at random as long as each one is unique. However, connecting a private network to the Internet requires using registered IP addresses (called Internet addresses) to avoid duplicates.

The four numbers in an IP address are used in different ways to identify a particular network and a host on that network. The InterNIC Registration Service assigns Internet addresses from the following three classes.

Class A - supports 16 million hosts on each of 127 networks

Class B - supports 65,000 hosts on each of 16,000 networks

Class C - supports 254 hosts on each of 2 million networks

The number of unassigned Internet addresses is running out, so a new classless scheme called CIDR is gradually replacing the system based on classes A, B, and C and is tied to adoption of IPv6.

Visit the provided below link to get the detailed information on IP addressing:

www.3com.com/solutions/en_US/ncs/501302.html

support.wrq.com/tutorials/tcpip/ipadd1.html

I want to connect my desktop to my laptop, and would like to synchronise the files between the two. Please explain in details how to set up this one-to-one network.

You can connect from Laptop to PC through Serial-to- Serial port or Parallel- to-Parallel port connection by using direct cable connection.

To transfer files from one computer to another it may be required that a direct serial cable connection be setup.

Requirements for Direct cable connection

1. Direct Cable Connection must be on both computers.

2. You must have a bi-directional serial or parallel port cable or null modem cable

Please carry out the following to configure Direct Cable connection:

1. For the following steps to work properly you must already have or purchase a Null Modem Cable and must be connected directly to each of the computers you plan to connect to.

2. For Direct Cable connection to work you must fist install the software used for the communication. To install Direct Cable Connection click Start - Settings - Control Panel. Double click on Add Remove Programs, click the Windows Setup tab. Now double click the Communications icon and check the Direct Cable Connection box. If this box is already installed it is recommended that you uncheck the box and then place the check back in the box to ensure that the complete program is installed into the computer. Once completely installed, reboot the computer.

3. Once back in Windows click Start - Settings - Control Panel. Double click on Network and install the following components.

4. Double click My Computer, right click on the drive you wish to share your information on. (Usually this would be Drive C). Once the Properties window for the drive is open click the Sharing tab and choose the option for Shared As. Ensure a name is entered in Share Name. Click the apply button and reboot the computer to ensure the changes have taken effect.

5. Once the above steps have been completed you must then decide which computer would be the host and which computer would be the guest. Once this is determined first setup the host computer by clicking on Start - Programs - Accessories - Communications. Click on Direct Cable Connection. In the Direct Cable Connection box choose the option for host; choose the communications port that you wish to set this computer to. Click Next your computer will then wait for the guest computer to send signal to the host computer.

6. Once the above steps have been completed for the second computer in setting up and configuring the Direct Cable Connection. Click Start - Programs - Accessories -Communications. Click on Direct Cable Connection. In the Direct Cable Connection box choose the option for guest, choose the communications port that you wish to set this computer to. Click Next and the computer will begin to look for the host computer.

7. Once the host and the guest have been setup you should establish a connection to be able to browse the hard drive that has been shared through Network neighborhood.

Now you can transfer the required files from your laptop to your computer.

Please www.helmig.com/j_helmig/dccmain.htm for more details about setting up Direct Cable Connection.

Why TCP sequence number wraps around?

1. Sequence number wrap-around depending upon the current connection. A TCP sequence number contains 32 bits. At a high enough transfer rate, the 32-bit sequence space may be "wrapped" (cycled) within the time that a segment is delayed in queues.

2. Earlier incarnation of the connection: Suppose that a connection terminates, either by a proper close sequence or due to a host crash, and the same connection (i.e., using the same pair of sockets) is immediately reopened. A delayed segment from the terminated connection could fall within the current window for the new incarnation and be accepted as valid.

Please visit the following link for more information about the topic:

http://andrew2.andrew.cmu.edu/rfc/rfc1185.html

For a Cybercafe with strength of 7 computers, which network is recommended, Client/server network or peer-to-peer network?

For a Cybercafe containing 7 computers a peer-to-peer network would be recommended, due to following reasons:

1. A peer-to-peer network allows two or more PCs to pool their resources together. Individual resources like disk drives, CD-ROM drives, and even printers are transformed into shared, collective resources that are accessible from every PC.

2. Unlike client-server networks, where network information is stored on a centralized file server and made available to tens, hundreds, or thousands client PCs, the information stored across peer-to-peer networks is uniquely decentralized. Because peer-to-peer PCs have their own hard disk drives that are accessible by all computers, each PC acts as both a client (information requestor) and a server (information provider).

3. A peer-to-peer network can be built with either 10BaseT cabling and with or without a hub. 10BaseT is best for small workgroups of 16 or fewer users that do not span long distances, or for workgroups that have one or more portable computers that may be disconnected from the network from time to time.

The advantages of peer-to-peer over client-server include:

1. No need for a network administrator

2. Network is fast/inexpensive to setup & maintain

3. Each PC can make backup copies of its data to other PCs for security.

4. Easiest type of network to build, peer-to-peer is perfect for both home and office use.

I have recently installed cable Internet in my house. The computer that has the Internet has two Ethernet cards, one is being used for Net access. I have run a cable from one Ethernet card to the Ethernet card on the other computer. I can not find a way to get the computers to communicate.

1. Since you are using a cable modem, you will be asked to select a network adapter (NIC). Be sure you choose the adapter that is attached to your cable modem. If you don't choose the correct NIC, ICS won't install correctly and you'll probably have to remove and reinstall it and try again. You will see that the ICS Wizard numbers your NIC's #1 and NIC #2, but there is no clue as to which is connected to the cable modem and which is connected to your LAN. You will have to guess, and if you guess wrong, you get to go through the whole process again.

2. If any of your client computers are set to "Obtain an IP address automatically" (from a DHCP server), you should shut down those computers before you install ICS. That is to make sure that the IP information assigned by the old DHCP server doesn't interfere with the information assigned by the ICS DHCP server.

3. If you already have another sharing application like Sygate or Wingate installed, uninstall it, before installing ICS. Some sharing programs (ICS included) take control of one or more of your Network adapters and/or Protocols, and having more than one program trying to control them can lead to conflicts.

4. The Microsoft ATM adapter does not work with ICS. Hybrid services like DirecPC and one-way cable modems with telco modem returns do not work with ICS.

Please visit the following link, for a diagrammatic representation of Running Internet Connection Sharing (ICS):

www.infinisource.com/techfiles/ics-running.html

Please visit the following link for information about troubleshooting Internet Connection Sharing:

www.infinisource.com/techfiles/ics-troubleshooting.html

I have a Windows 98 SE (ICS) network, used for Net sharing. I wish to limit the bandwidth to my clients, i.e. 4k to each Win PC on the LAN. How can I do it?

As far as we know, it is not possible to restrict allocation of bandwidth in a Local Area Network (LAN) meant for Internet access. Internet Connection Sharing network is a type of local area network that relies on a single computer called a gateway, through which all other computers and TCP/IP-capable devices connect to the Internet. The bandwidth distribution is done equally in ICS depending on the number of computers that are trying to access a connection at one point of time. For example, if one computer is trying to access a large file or streaming video it may not leave lot of spare bandwidth for other computers. This will cause the distribution of bandwidth to be uneven.

Visit the following link for information about ICS:

http://support.microsoft.com/support/kb/articles/q234/8/15.asp

However, if you are experiencing slow transfer rates with ICS and high-bandwidth devices, visit the following site for a solution:

http://support.microsoft.com/support/kb/articles/q230/1/16.asp