Agilent Technologies HSSI WanProbe J3916A - Manual (Page 165)

Glossary
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P/F (Poll/Final bit)
One of the bits of a control octet in HDLC derivative level 2 link protocols. In
commands it is called the Poll bit. In responses, the Final. Setting this bit to binary
1 in a command requires and immediate response. In a response, it indicates
compliance with the command.
P(R)
Receive packet number in X.25 packet headers.
P(S)
Send packet number in X.25 packet headers.
Packet
A bit stream consisting of predefined fields that contain data, addresses, and
control information. In the IEEE 802.3 environment, this structure is often
referred to as the MAC frame. Packet is used in the Ethernet environment and is
used in this guide because it is the more commonly understood term. Different
protocols have different packet and frame specifications.
Packet Switching
A network technology in which data transfers are “packetized” and sent through
the network one packet at a time. The network assume responsibility for routing
the packets.
Permanent Virtual circuit
A permanent virtual circuit is a permanent association between two DDS,
established by the user when subscribing to a packet-switched network and is
similar to a leased line.
Physical Layer (PL)
Level 1 of the seven level OSI reference model defined by ISO. The physical
layer provides for the physical transportation of cells across the network. It
consists of physical medium dependent (PMD) and transmission convergence
(TC) sublayers. Important categories are PDH, SDH and the physical media used
on local premises for LANs.
Point-to-point configuration
A remote configuration that has two Advisors connected to each end.