ID: q97599
The information in this article applies to:
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Remote Access generally supplies good default values for the Remote Access Service (RAS) parameters. However, for some systems, you may want to adjust individual parameters to suit your particular performance and security needs.
This article provides a complete list of parameters that can be adjusted in the Registry Database (use Registration Information Editor), arranged in the following categories:
WARNING: Using Registry Editor incorrectly can cause serious, system-wide problems that may require you to reinstall Windows NT to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.
For information on adding Registry values, see the online help provided for Registration Information Editor, or query on the following here in the the Microsoft Knowledge Base:
modify and ras and registry
Remote Access parameters are listed by parameter name and can be found in the following Registry subkey:
SYSTEM\CurrentControlSet\Services\RemoteAccess\Parameters
Parameter Range Use
AuthenticateRetries 0-10 Sets the maximum number of
default = 2 unsuccessful retries at
authentication.
AuthenticateTime 20-600 secs. Sets the maximum amount of time
default: 120 a user is allowed to finish
authentication.
CallbackTime 2-12 secs. Sets the time interval the
default: 2 server waits before calling the
client back; client communicates
the value of its own callback
time when connecting to a Remote
Access server. If the client does
not communicate a callback time
value (as with Remote Access
1.0 and 1.1 clients), the value
of this parameter is used.
EnableAudit 0 = disabled Enables or disables Remote
1 = enabled Access auditing
default: 1
NetbiosGatewayEnabled 0 = disabled Makes the server function like
1 = enabled a NetBIOS gateway, allowing
default: 1 clients to access the LAN. If
disabled, remote clients can
access the files on the server
in a point-to-point connection
only.
NumRecvQueryIndications 1-32 Allows Remote Access clients to
default: 3 initiate simultaneous, multiple
network connections.
In Windows NT 3.1, the NetBIOS Gateway parameters are listed by parameter name and can be found in the registry under the the HKEY_LOCAL_MACHINE subtree under the following subkey:
SYSTEM\CurrentControlSet\Services\RemoteAccess\Parameters
\NetbiosGateway\Parameters
SYSTEM\CurrentControlSet\Services\RemoteAccess\Parameters
Parameter Range Use
AutoDisconnect 0-60000 minutes. Sets the time interval after
default: 20 which inactive connections are
terminated. Inactivity is
measured by lack of session data
transfer. You may want to set
this parameter to 0 minutes if
clients are running NetBIOS
datagram applications. Setting
this parameter to 0 disables
AutoDisconnect.
DisableMcastFwd 0 = disabled Allows session traffic to have
WhenSessionTraffic 1 = enabled priority over multicast data-
default: 1 grams. This means that multicast
datagrams are transferred only
when there is no session traffic.
EnableBroadcast 0 = disabled Determines whether broadcast
1 = enabled datagrams are forwarded to
default: 0 remote workstations. See
MulticastForwardRate.
MaxBcastDgBuffered 16-255 Sets the number of broadcast
default: 32 datagrams that the gateway
buffers for a client.
MaxDgBufferedPer 1-255 Sets the number of datagrams
GroupName default: 10 that can be buffered per group
name. Because this setting is
done in virtual memory, you can
set it high.
MaxDynMem 131072- Sets the amount of virtual
4294967295 memory used to buffer NetBIOS
default: 655350 session data for each remote
client. (See Note 1, below.)
MaxNames 1-255 Sets the number of unique
default: 255) NetBIOS names that each client
can have. NetBIOS stacks on the
LAN have a maximum of 255 names
allocated for all clients
(cumulative). For example: To
allow 64 clients to connect
simultaneously, set this
parameter to 3 or 4.
MaxSessions 1-255 Sets the maximum number of
default: 255 simultaneous NetBIOS sessions
each client can have. NetBIOS
stacks on the LAN have a maximum
of 255 names allocated for all
clients. (See Note 2, below.)
MultiCast -1 to Governs the multicasting of
ForwardRate 4294967295 server announcements (group name
secs datagrams) to all remote work-
default: 5 stations in a server's domain.
-1 Disables forwarding.
0 Guarantees delivery of group
name datagrams.
n Forwards datagrams every n
seconds.
(See Note 3, below.)
RcvDgSubmitted 1-32 Determines how many NetBIOS
PerGroupName default: 3 Receive Datagram commands can be
submitted simultaneously for each
group name on the LAN stack. Keep
this setting as small as possible
to minimize the amount of memory
consumed by system resources. Each
datagram command received locks
about 1.5K of physical memory in
the system.
RemoteListen 0-2 Sets the remote NCB_LISTEN capa-
default: 1 bility. (Microsoft recommends
using the default value.)
0 Client can't post NCB_LISTEN
for any NetBIOS name.
1 Remote client can receive
messages from LAN users and
printers. Client can post
NCB_LISTEN on Windows NT
Advanced Server aliases only.
2 Enables NCB_LISTEN for all
remote client NetBIOS names,
enabling them to run NetBIOS
server applications and to
act as servers on the network.
(See Note 4, below.)
SizWorkBufs 1024-65536 Sets the size of work buffers.
default: 4500 The default setting is optimized
for the server message block (SMB)
protocol, the protocol between the
workstation and the server running
on Windows NT Advanced Server.
1. Because the Remote Access server is a gateway between the slow
line and the LAN, data is buffered in its memory when coming from
the fast line (LAN) to the slow (asynchronous) line. The Remote
Access server minimizes the usage of physical memory by locking
only a minimal set of pages (about 64K per client) and making use
of virtual memory to buffer the rest of the data. As long as you
have enough disk space on your backup store, you can increase
this parameter if needed.
If you have an application with a LAN (fast) sender and an
async (slow) receiver, and if the sender is sending more data at
a time than the Remote Access server can buffer, the Remote
Access server tries to apply a form of NetBIOS level flow control
by not submitting NCB_RECEIVE on the session, until it has
enough buffer space to store incoming data. In this situation,
you should increase your NetBIOS SEND and RECEIVE time-outs so
that the fast sender can keep pace with the slow receiver.
This removes any limit on how much memory NetBEUI allows itself
to use. A size of 2 means a limit of 300K, which is enough for
about 64 normalconnections. The Registry subkey for this parameter
is SYSTEM\CurrentControlSet\Services\Nbf\Parameters.
may appear as a continuous stream of datagrams directed to
remote workstations. Because these announcements are repeated,
they waste CPU cycles at workstations without any real information
gain in return.The MultiCastForwardRate parameter makes it possible
to filter server announcements by forwarding them at a specified
interval.
If the EnableBroadcast parameter is set to 0, then broadcasts are
not forwarded, even if the MultiCastForwardRate parameter is set
to a positive number (in this case, only multicast datagrams are
forwarded). If MultiCastForwardRate is set to -1, then broadcasts
are still not forwarded even if EnableBroadcast is set to 1. (See
the EnableBroadcast parameter.)
If the RemoteListen parameter is configured to 2, Remote Access
posts an NCB_LISTEN on all NetBIOS names of Remote Access clients.
Considering that the average Windows NT Advanced Server workstation
has about 5 NetBIOS names assigned to it, the total number of
NetBIOS names for which an NCB_LISTEN would be posted is 5 times 64
(the maximum number of clients per Remote Access server).
Asynchronous Media Access Control (MAC) parameters are listed by parameter name and can be found in the following Registry subkey:
SYSTEM\CurrentControlSet\Services\AsyncMacn\Parameters
Parameter Range Use
FramesPerPort 2-20 Allocates frames for each dial-in
default: 3 or dial-out port. Set this value
to the number of frames the
transport may have outstanding at
any given time.
IrpStackSize 1-10 Sets the number of device drivers
default: 5 MAC is layered above. Increase
this value only if the serial
driver below the MAC needs more
stack size.
MaxFrameSize 576-1514 Determines the maximum frame size
default: 1514 Use smaller frames for noisy links.
RAS Hub parameters are listed by parameter name and can be found in the following Registry subkey:
SYSTEM\CurrentControlSet\Services\RasHub\Parameters
Parameter Range Use
NetworkAddress ----- Reassigns the first 4 bytes of the
6-byte IEEE address. For example,
if you reset the address to
"03-1F-2C-81-92-34," only the first
4 bytes are looked at. Reset this
parameter in the RasHub\Parameters
subkey with the REG_SZ data type.
Keywords : kbnetwork
Version : 1.0 1.1 3.1
Platform : WINDOWSLast Reviewed: August 19, 1998