Agilent Technologies 622Vu Advisor, User Manual

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Real-time statistics
Feature of 622Vu Advisor that’s available any time you’re not capturing
traffic actively. Allows you to monitor real-time statistics for the link attached to an analysis
device, and to display the active network connections on the link. Each time 622Vu Advisor
detects a new connection, it displays the corresponding VP/VC identifiers and begins tracking
statistics for that connection. If you notice a problem while monitoring the statistics, you can
begin capturing any particular VCC(s) through a special filtering capability available via real-
time statistics.
SAAL
Signaling ATM Adaptation Layer (uses AAL5).
SAR
See Segmentation and Reassembly (SAR) sublayer.
SC Sequence count, in the range hex 0–7 (specified during sequence definition when using AAL1
cell framing).
SCCP
Signaling Connection and Control Part.
script
Instructions that describe the transmission pattern you want to send out across an ATM
network. A script sends cells in specific order, and each cell has a specific content, both in its
header and payload.
Segmentation and Reassembly (SAR) sublayer
One of two sublayers in each AAL (ATM
Adaptation Layer protocol), as currently specified by the ITU. On the sending end of ATM
transmissions, the SAR sublayer receives datagrams, video frames, etc., from the CS
(Convergence Sublayer), and is responsible for breaking that data into cell-sized pieces, then
mapping that data into the cell payloads of an ATM cell stream. On the receiving end, the
SAR sublayer is responsible for retrieving data from the cell payloads and reassembling it into
its original form (datagrams, video frames, etc.), then forwarding that data to the CS. See
ATM Adaptation Layer for more information.
sender
Within the context of ATM, the host (computer) that initially sends a cell over the
network. Also used to refer to the host user or application responsible for sending the cell.
sequence
Within 622Vu Advisor, a named set of cells that can be referenced as a single entity by
using the sequence name. Each entry in the sequence comprises a:
•
cell name — a descriptive name.
•
repetition count specifying how many consecutive copies of the cell occur in that table
entry; i.e., at this point in the containing sequence.
Before a sequence is transmitted, it’s expanded into one contiguous stream of cells (by using
the repeat counts), then it’s transmitted to the DUT as a single burst.
signaling software
Software responsible for enforcing the signalling (or setup) portion of the
ATM protocol suite. Before ATM cells can be transmitted, the signalling software establishes
a connection between the sender and receiver, and assigns a channel identifier (VPI/VCI) to
the connection at each hop. Signaling software resides in each ATM device, and somewhere
in the sender and receiver’s equipment. Each device is responsible for contacting (and setting
up communication with) the next device in the path between the two hosts.
SN
Serial number, in the range hex 0–F (specified during sequence definition when using AAL1
cell framing).
SNA
Systems Network Architecture — One of several protocol suites commonly used to
communicate over an internet, this one defined by IBM.
SNAP
Sub Network Access Protocol.
SNMP
Simple Network Management Protocol. A tool that runs on top of IP to facilitate
standardized management of all types of network devices. SNMP allows the Network
Manager to obtain a simple set of information about each device in the network.
A: Glossary
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