This section documents the Windows 98 registry entries for TCP/IP.
Configuration settings for Microsoft TCP/IP are stored in the Registry as part of the protocol installation process. If Dynamic Host Configuration Protocol (DHCP) is used on the network, configuration information can also be provided by DHCP client service. DHCP-provided information is stored in the registry in binary format and cannot be altered by editing it. However, static information can be entered in the registry, which overrides DHCP default values.
The value entries are added to the following registry key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP
Descriptions of the TCP/IP values in the MSTCP are described in Table 31.18 (all data types are DWORD).
Table 31.18 TCP/IP registry entries
| Value | Description |
|---|---|
| BroadcastAddress = broadcast address in hexadecimal | Specifies the address to use for NetBIOS name query broadcasts. The default is based on the Internet Protocol (IP) address and the subnet mask. |
| BcastNameQueryCount = integer | Specifies the number of times the system will retry NetBIOS name query broadcasts. The default is 3. |
| BcastQueryTimeout = milliseconds | Specifies the period of time the system will wait before timing out broadcast name queries. The minimum value is 100. The default is 750. |
| BSDUrgent = 0 or 1 | If this value is 1, it specifies that Microsoft TCP/IP is to treat urgent data the way some UNIX systems do (with a maximum of 1 byte of urgent data, for example). If this value is 0, it specifies that the stack is to handle urgent data as specified by RFC 1122. The default is 1. |
| CacheTimeout = milliseconds | Specifies how long NetBIOS names are cached. The minimum is 60,000 milliseconds (1 minute). The default is 360,000 milliseconds (6 minutes). |
| DeadGWDetect = 0 or 1 | Specifies whether Microsoft TCP/IP will use another gateway if the current default gateway seems to be down. The default is 1. |
| DefaultRcvWindow = 16-bit number | Specifies the default receive window advertised by TCP. The default is 8192. |
| DefaultTOS = 8-bit number | Specifies the default type of service (TOS) for IP packets initiated by Microsoft TCP/IP. The default is 0. |
| DefaultTTL = 8-bit number | Specifies the default time to live (TTL) for IP packets initiated by Microsoft TCP/IP. The default is 128. |
| DnsServerPort = port | Specifies which DNS server port to send queries to when resolving a name using DNS. The default is 53. |
| EnableProxy = 0 or 1 | If this value is 1, it specifies that this computer is a Windows Internet Naming Service (WINS) proxy agent. The default is 0. |
| EnableRouting = 0 or 1 | Specifies whether to enable static routing. Microsoft TCP/IP does not supply a routing protocol, so all route table entries must be entered using the route command. The default is 0. |
| IGMPLevel = 0, 1, or 2 | Specifies the level of support allowed for IP multicast, corresponding to the levels in RFC 1112. The default is 2. |
| InitialRefreshT.O. = milliseconds | Specifies the interval over which to contact WINS to refresh the name. The minimum is 16 minutes, and the maximum is approximately 50 days (0xFFFFFFFF). The default is 960,000 milliseconds (16 minutes). |
| KeepAliveTime = 32-bit number | Specifies the connection idle time in milliseconds before TCP will begin sending keepalives, if keepalives are enabled on a connection. The default is 2 hours (7,200,000 milliseconds). |
| KeepAliveInterval = 32-bit number | Specifies the time in milliseconds between retransmissions of keepalives, once the KeepAliveTime has expired. Once KeepAliveTime has expired, keepalives are sent every KeepAliveInterval milliseconds until a response is received, up to a maximum of MaxDataRetries before the connection is aborted. The default is 1 second (1000 milliseconds). |
| LmhostsTimeout = milliseconds | Specifies the period of time the system will wait before timing out when seeking LMHOSTS for name resolution. The minimum value is 1000 milliseconds (1 second). The default is 10,000 milliseconds (10 seconds). |
| MaxConnections = 32-bit number | Specifies the maximum number of concurrent connections. The default is 100. |
| MaxConnectRetries = 32-bit number | Specifies the number of times a connection attempt (SYN) will be retransmitted before giving up. The initial retransmission timeout is 3 seconds, and it is doubled each time up to a maximum of 2 minutes. The default is 3. |
| MaxDataRetries = 32-bit number | Specifies the maximum number of times a segment carrying data or FIN will be retransmitted before the connection is aborted. The retransmission timeout itself is adaptive and will vary according to link conditions. The default is 5. |
| NameServerPort = port | Specifies the User Datagram Protocol (UDP) port on the name server to which to send name queries or registrations. The default is 137. |
| NameSrvQueryCount = integer | Specifies the number of times the system will try to contact the WINS server for NetBIOS name resolution. The default is 3. |
| NameSrvQueryTimeout = milliseconds | Specifies how long the system waits before timing out a name server query. The minimum is 100 milliseconds. The default is 750 milliseconds. |
| NameTableSize = integer | Specifies the maximum number of names in the NetBIOS name table. The minimum allowable value is 1 and the maximum is 255. The default is 17. |
| NodeType = 1, 2, 4, or 8 | Specifies the mode of NetBIOS name resolution used by NetBIOS over TCP/IP, where 1 = b-node, 2 = p-node, 4 = m-node, and 8 = h-node. This value can be configured using DHCP. The default is 1 (b-node) if no value is specified; if WINS servers are specified and NodeType is not, the default is 8 (h-node). |
| PMTUBlackHoleDetect = 0 or 1 | Specifies whether the stack will attempt to detect Maximum Transmission Unit (MTU) routers that do not send back Internet Control Message Protocol (ICMP) fragmentation-needed messages. Setting this parameter when it is not needed can cause performance degradation. The default is 0. |
| PMTUDiscovery = 0 or 1 | Specifies whether Microsoft TCP/IP will attempt to perform path MTU discovery as specified in RFC 1191. The default is 1. |
| RandomAdapter = 0 or 1 | For a computer with multiple network adapters, specifies whether to respond with an IP address selected randomly from the set of addresses on the computer or whether to return the IP address of the adapter that the request came in upon. The default is 0 (not random; that is, return the address of the adapter that the request came in upon). |
| RoutingBufSize = 32-bit number | Specifies the total amount of buffer space to allocate for routing packets. This parameter is ignored if EnableRouting=0. The default is 73,216. |
| RoutingPackets = 32-bit number | Specifies the maximum number of packets that can be routed simultaneously. This parameter is ignored if EnableRouting=0. The default is 50. |
| SessionKeepAlive = milliseconds | Specifies how often to send session keepalive packets on active sessions. The minimum is 60 seconds. The default is 3,600,000 milliseconds (1 hour). |
| SessionTableSize = integer | Specifies the maximum number of sessions in the NetBIOS session table. The minimum allowable value is 1 and the maximum is 255. The default is 255. |
| SingleResponse = 0 or 1 | For a computer with multiple network adapters, specifies whether to send all IP addresses on a name query request from WINS. If this value is 1, the system will send one address in a name query response; if 0, it will return all the addresses of its adapters. The default is 0. |
| Size/Small/Medium/Large = 1, 2, or 3 | Specifies how many buffers of various types to pre-allocate and the maximum that can be allocated, where 1 = small, 2 = medium, and 3 = large. The default is 1; the default is 3 if the WINS proxy is enabled. |
This section describes variables for subkeys that appear in the following registry key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP\ServiceProvider
The Class and ProviderPath values are used by the service resolution and registry APIs in Windows Sockets. The Class parameter indicates that TCP/IP is a name service provider, and its binary value (8) should not be changed. The ProviderPath parameter is a string that defines the location and file name for the 32-bit Windows Sockets DLL (the default is %windir%\system\wsock32.dll).
The following keys describe the order used to resolve host names. A lower number sets a higher priority for name resolution. These settings are used for 16-bit Windows Sockets, which need to rely on the resolvers that are expected to take the least time. The numbers indicate the default values specified in Windows 98.
LocalPriority = 0x1F3 (499)HostsPriority = 0x1F (500)DNSPriority = 0x7D0 (2000)NetbtPriority = 0x7D1 (2001)
The entries in this section must be added to the following registry key, where n represents the particular TCP/IP-to-network adapter binding.
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\netTrans\000n
| Value | Data type | Description |
|---|---|---|
| MaxMTU = 16-bit integer | DWORD | Specifies the maximum size datagram IP that can pass to a media driver. Subnetwork Access Protocol (SNAP) and source routing headers (if used on the media) are not included in this value. For example, on an Ethernet network, MaxMTU will default to 1500. The actual value used will be the minimum of the value specified with this parameter and the size reported by the media driver. The default is the size reported by the media driver; an Ethernet network defaults to 1500 bytes and a Point-to-Point (PPP) Protocol dial-up connection defaults to 576 bytes. |
| ZeroBroadcast = 0 or 1 | String | If this parameter is set to 1, then IP will use zeros-broadcasts (0.0.0.0.) instead of ones-broadcasts (255.255.255.255). Most systems use ones-broadcasts, but some systems derived from BSD implementations use zeros-broadcasts. Interoperation will not work well on the same network for systems that use different broadcasts. Valid Range 0 or 1 (false or true); Default: 0 |
The TCP/IP node type can be manually changed by editing the Windows 98 registry. The location is under the HKEY_LOCAL_MACHINE key under the following subkey:
\System\CurrentControlSet\Services\VxD\MSTCP\NodeType
The four TCP/IP node types are defined by number:
| Number | Node Type | Description |
|---|---|---|
| 1 | b-node | Broadcast only |
| 2 | p-node | WINS only |
| 4 | m-node | Broadcast, then WINS |
| 8 | h-node | WINS, then broadcast |
The default Windows 98 TCP/IP node types are: