S
SIS (Simple Instruction Set) A set of commands developed by Extron that allow control of the
PC1 via the keyboard of a PC with an Ethernet connection. A minimal number of characters
are used in these commands and responses.
SMTP (Simple Mail Transfer Protocol) An Internet standard for e-mail exchange across systems
or networks on the Internet
Standby reference threshold
The point at which a device starts to operate at standby power
Static IP An IP address that has been specifically (instead of dynamically (see DHCP) assigned
to a device or system in a network configuration. This type of address requires manual
configuration of the actual network device or system and can be changed only manually or
by enabling DHCP.
Subnet See Subnetwork.
Subnet address The portion of an IP address that is specifically identified by the subnet mask as the
subnetwork
Subnet mask A 32-bit address mask used in IP to identify the bits of an IP address that are used for the
subnet address. Using a mask, the router does not need to examine all 32 bits, only those
selected by the mask.
Subnetwork (or Subnet) A network that is part of a larger IP network and is identified by a subnet
address. Networks can be segmented into subnetworks to provide a hierarchical, multilevel
routing structure.
T
TCP (Transmission Control Protocol) A connection-oriented protocol defined at the Transport
layer of the OSI reference model. It provides reliable delivery of data.
TCP/IP (Transmission Control Protocol/Internet Protocol) The communication protocol
(language) of the Internet. Computers and devices with direct access to the Internet are
provided with a copy of the TCP/IP program to allow them to send and receive information
in an understandable form.
Telnet (Telecommunication Network) A utility available on most PCs that allows the computer
system to communicate with one of its remote users or clients. A user who wishes to access
a remote system initiates a Telnet session, using the address of the remote client. The user
may be prompted to provide a user name and password if the client is set up to require
them.
U, W
UID (User ID) An optional user name for which a field is provided on the Enter Password
window that opens if a password has been assigned to the PC1
URL (Universal Resource Locator) An address that lets a resource on the internet be identified,
located, and accessed
IPL T PC1 • Glossary 70