Appendix C:
Glossary
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RSTP
In 1998, the IEEE with document 802.1w introduced an evolution of STP:
the
R
apid
S
panning
T
ree
P
rotocol, which provides for faster spanning tree convergence after
a topology change. Standard IEEE 802.1D-2004 now incorporates RSTP and obsoletes STP,
while at the same time being backwards-compatible with STP.
S
sFlow
sFlow is an industry standard technology for monitoring switched networks through random
sampling of packets on switch ports and time-based sampling of port counters. The sampled
packets and counters (referred to as flow samples and counter samples, respectively) are
sent as sFlow UDP datagrams to a central network traffic monitoring server. This central
server is called an sFlow receiver or sFlow collector.
Shaper
A shaper can limit the bandwidth of transmitted frames. It is located after the ingress queues.
SMTP
SMTP is an acronym for
S
imple
M
ail
T
ransfer
P
rotocol. It is a text-based protocol that uses
the Transmission Control Protocol (TCP) and provides a mail service modeled on the FTP file
transfer service. SMTP transfers mail messages between systems and notifications regarding
incoming mail.
SNAP
The
S
ub
N
etwork
A
ccess
P
rotocol (SNAP) is a mechanism for multiplexing, on networks
using IEEE 802.2 LLC, more protocols than can be distinguished by the 8-bit 802.2 Service
Access Point (SAP) fields. SNAP supports identifying protocols by Ethernet type field values;
it also supports vendor-private protocol identifier.
SNMP
SNMP is an acronym for
S
imple
N
etwork
M
anagement
P
rotocol. It is part of the Transmission
Control Protocol/Internet Protocol (TCP/IP) protocol for network management. SNMP allow
diverse network objects to participate in a network management architecture. It enables
network management systems to learn network problems by receiving traps or change
notices from network devices implementing SNMP.
SNTP
SNTP is an acronym for
S
imple
N
etwork
T
ime
P
rotocol, a network protocol for synchronizing
the clocks of computer systems. SNTP uses UDP (datagrams) as transport layer.
