User's Manual

User’s Manual of SGS-5240 Series Managed Switch
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An alternative protocol is Internet Message Access Protocol (IMAP). IMAP provides the user with more capabilities
for retaining e-mail on the server and for organizing it in folders on the server. IMAP can be thought of as a remote
file server.
POP and IMAP deal with the receiving of e-mail and are not to be confused with the Simple Mail Transfer Protocol
(SMTP). You send e-mail with SMTP, and a mail handler receives it on your recipient's behalf. Then the mail is
read using POP or IMAP. IMAP4 and POP3 are the two most prevalent Internet standard protocols for e-mail
retrieval. Virtually all modern e-mail clients and servers support both.
Pepo
PPPoE is an acronym for Point-to-Point Protocol over Ethernet. It is a network protocol for encapsulating Point-to-Point
Protocol (PPP) frames inside Ethernet frames. It is used mainly with ADSL services where individual users connect to
the ADSL transceiver (modem) over Ethernet and in plain Metro Ethernet networks (Wikipedia).
Private VLAN
In a private VLAN, communication between ports in that private VLAN is not permitted. A VLAN can be configured as a
private VLAN.
PTP
PTP is an acronym for Precision Time Protocol, a network protocol for synchronizing the clocks of computer systems.
Q
QCE
QCE is an acronym for Qu’s Control Entry. It describes Qu’s class associated with a particular QCE ID.
There are six QCE frame types: Ethernet Type, VLAN, UDP/TCP Port, DSCP, TOS, and Tag Priority. Frames can
be classified by one of 4 different Qu’s classes: "Low", "Normal", "Medium", and "High" for individual application.
QCL
QCL is an acronym for Qu’s Control List. It is the list table of QCEs, containing Qu’s control entries that classify to a
specific Qu’s class on specific traffic objects.
Each accessible traffic object contains an identifier to its QCL. The privileges determine specific traffic object to
specific Qu’s class.
QL
QL In SyncE this is the Quality Level of a given clock source. This is received on a port in a SSM indicating the quality
of the clock received in the port.
Qu’s
Qu’s is an acronym for Quality of Service. It is a method to guarantee a bandwidth relationship between individual
applications or protocols.
A communications network transports a multitude of applications and data, including high-quality video and
delay-sensitive data such as real-time voice. Networks must provide secure, predictable, measurable, and
sometimes guaranteed services.
Achieving the required Qu’s becomes the secret to a successful end-to-end business solution. Therefore, Qu’s is
the set of techniques to manage network resources.
Qu’s class
Every incoming frame is classified to a QoS class, which is used throughout the device for providing queuing,
scheduling and congestion control guarantees to the frame according to what was configured for that specific Qu’s
class. There is a one to one mapping between Qu’s class, queue and priority. A Qu’s class of 0 (zero) has the
lowest priority.
R
RARP
RARP is an acronym for Reverse Address Resolution Protocol. It is a protocol that is used to obtain an IP address for a