Lucent Technologies SLC ConnectReach User & Service Manual page 524

Glossary 363-208-050
Ground-Start/Loop-Start — Two common telephone trunk signaling schemes. In ground-start signaling,
the device at one end of the connection grounds one side of the line and the device at the other end
detects the presence of the ground. In loop-start signaling, one device closes the loop and the resulting
current flow is detected by the device at the other end. PBX systems usually are connected to ground-start
trunks, and single telephone lines and key systems to loop-start trunks. The SLC ConnectReach system
supports both, and automatically detects for channel bank which signaling scheme is used on a line-by-line
basis.
H
HDLC — High-level Data Link Control. A communications protocol for point-to-point and multipoint
communications that reduces the likelihood of errors.
HLU — HiGain Line Unit (master).
HRU — HiGain Remote Unit (slave).
Host Number — The low bits of an IP address which corresponds to those bits in the associated subnet
mask which have 0's.
HTTP — HyperText Transfer Protocol. The protocol used for communication between World Wide Web
servers and Web browsers.
I
ICMP — Internet Control Message Protocol. A low-level protocol that supports functions such as echo
requests and "host not available" messages.
Immediate Start — A type of trunk signaling for incoming and outgoing calls. This signaling indicates that
the originating trunk goes off-hook, and maintains this condition for at least 150 milliseconds. Then the
originating trunk sends out digits.
Incoming — A call that comes from the CO to a user on the SLC ConnectReach system.
Internet — Largest global internetwork, connecting tens of thousands of networks worldwide and having a
"culture" that focuses on research and standardization based on real-life use.
IOR — Intelligent Office Repeater.
IP — Internet Protocol. The network-layer protocol in the TCP/IP protocol stack.
IP Address — A 32-bit address (specified as x.y.z.w) which is assigned to hosts in a TCP/IP Internet. This
32-bit address is comprised of a network portion and a host portion.
IP Unnumbered Interface — This describes an interface that does not consume a unique IP address.
GL-6
Issue 4 June 2002