D-Link xStack DES-3228PA, Руководство по установке в сети

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DES-3228PA Embedded Web System User Guide
Page 235
SNTP
The Simple Network Time Protocol (SNTP) assures accurate net-
work Ethernet Switch clock time synchronization up to the milli-
second. Time synchronization is performed by a network SNTP
server. Time sources are established by Stratums. Stratums
define the distance from the reference clock. The higher the stra-
tum (where zero is the highest), the more accurate the clock.
Spanning Tree Protocol
802.1d Spanning tree is a standard Layer 2 switch requirement
that allows bridges to automatically prevent and resolve L2 for-
warding loops. Switches exchange configuration messages using
specifically formatted frames and selectively enable and disable
forwarding on ports.
SSH
Secure Shell (SSH) is a protocol that provides a secure, remote
connection to a device. SSH version 2 is currently supported. The
SSH server feature enables an SSH client to establish a secure,
encrypted connection with a device. This connection provides
functionality that is similar to an inbound telnet connection. SSH
uses RSA and DSA Public Key cryptography for device connec-
tions and authentication.
SSL
Secure Socket Layer (SSL) is an application-level protocol that
enables secure transactions of data through privacy, authentica-
tion, and data integrity. It relies upon certificates and public and
private keys.
Static MAC Entries
MAC entries can be manually entered in the Bridging Table, as an
alternative to learning them from incoming frames. These user-
defined entries are not subject to aging, and are preserved across
resets and reboots.
TCP
Transport Control Protocol (TCP). TCP connections are defined
between 2 ports by an initial synchronization exchange. TCP
ports are identified by an IP address and a 16-bit port number.
Octets streams are divided into TCP packets, each carrying a
sequence number.
TFTP Trivial File Transfer Protocol
The device supports boot image, software and configuration
upload/download via TFTP.
Traceroute
Traceroute discovers IP routes that packets were forwarded
along during the forwarding process. The CLI Traceroute utility
can be executed from either the user-exec or privileged modes.
Virtual Cable Testing
VCT detects and reports copper link cabling occurrences, such as
open cables and cable shorts.
VLAN Support
VLANs are collections of switching ports that comprise a single
broadcast domain. Packets are classified as belonging to a VLAN
based on either the VLAN tag or based on a combination of the
ingress port and packet contents. Packets sharing common
attributes can be grouped in the same VLAN.
F e a t u r e D e s c r i p t i o n