NetDAQ Users Manual

Network Considerations
Glossary I
I-35
change to TCP/IP is contemplated, an RFC is issued over the Internet and
everyone is invited to comment on the change before its implementation.
Router A router provides a communication path between two or more sections of
a network. It directs packets between sections (subnets) of the network so that
only those packets addressed to hosts (or other routers) within the subnet are
communicated to that subnet.
Server A computer that provides services (such as file, print, and database
services) to other computers on a network.
Shim A driver-like TSR that translates the interface of a driver of one type to
communicate with protocol stacks that expect to communicate with a driver of a
different type. In most cases this is a TSR that allows stacks that can operate only
over NDIS or ODI drivers to use another type of driver (such as a packet driver).
Socket A two-way pipe-like connection between an application port in one host
and an application port in another host. Once a socket is established between two
hosts, everything that is placed in the output socket of one host will appear in the
input socket of the other host. An API to the socket functions of TCP is provided
by WINSOCK.
Subnet A portion of the network that is partially isolated from other sections of
the net by a router device. In IP networks, the upper portion of the IP address
defines the subnet and the lower portion is unique for each host computer.
Subnet Mask A 32-bit pattern that is used to separate the subnet portion from the
host portion of an IP address. This mask is used to determine whether an
addressed host is on the local subnet, or if the packet needs to be communicated to
a different subnet through a router.
TCP Transmission Control Protocol. The high level portion of the TCP/IP
protocol. It is responsible for providing reliable, securable, end-to-end connection
service between pairs of processes in hosts on the network. It must provide
facilities for:
• Basic Data Transfer
• Reliability (retry, sequence numbering)
• Flow Control (ACK/NACK)
• Multiplexing (socket ports)
• Connections (Sockets)
• Precedence and Security
TSR Terminate and Stay Resident. A DOS program that, when run, leaves a
portion of itself resident upon termination.
Token Bus One type of physical network standardized by IEEE-802.4.
Token Ring One type of physical network standardized by IEEE-802.5.