3Com OfficeConnect 3CDSG8 User Manual page 70

70
Feature
Command Line Interface
Configuration File Management
DHCP Clients
Domain Name System
Fast Link
Full 802.1Q VLAN Tagging Compliance
IGMP Snooping
LACP
Link Aggregated Groups
Description
The Command Line Interface (CLI) is an interface using a serial
connection that allows basic features to be configured, including IP
address management and firmware upgrading. The CLI is not intended
as the main interface for the switch.
The device configuration is stored in a configuration file. The
Configuration file includes both system wide and port specific device
configuration. The system can display configuration files in the form of
a collection of CLI commands, which are stored and manipulated as text
files.
Dynamic Host Client Protocol. DHCP enables additional setup
parameters to be received from a network server upon system startup.
DHCP service is an on-going process.
Domain Name System (DNS) converts user-defined domain names into
IP addresses. Each time a domain name is assigned the DNS service
translates the name into a numeric IP address. For example,
www.ipexample.com is translated to 192.87.56.2. DNS servers maintain
domain name databases and their corresponding IP addresses.
STP can take up to 30-60 seconds to converge. During this time, STP
detects possible loops, allowing time for status changes to propagate
and for relevant devices to respond. 30-60 seconds is considered too
long of a response time for many applications. The Fast Link option
bypasses this delay, and can be used in network topologies where
forwarding loops do not occur.
IEEE 802.1Q defines an architecture for virtual bridged LANs, the
services provided in VLANs and the protocols and algorithms involved in
the provision of these services. An important requirement included in
this standard is the ability to mark frames with a desired Class of Service
(CoS) tag value.
IGMP Snooping examines IGMP frame contents, when they are
forwarded by the device from work stations to an upstream Multicast
router. From the frame, the device identifies work stations configured
for Multicast sessions, and which Multicast routers are sending
Multicast frames.
LACP uses peer exchanges across links to determine, on an ongoing
basis, the aggregation capability of various links, and continuously
provides the maximum level of aggregation capability achievable
between a given pair of systems. LACP automatically determines,
configures, binds and monitors the port binding within the system.
The system provides up to four Link Aggregated Groups (LAGs).
Aggregated Links may be defined, each with up to eight member ports,
to form a single LAG. LAGs provide:
Fault tolerance protection from physical link disruption
Higher bandwidth connections
Improved bandwidth granularity
High bandwidth server connectivity
LAG is composed of ports with the same speed, set to full-
duplex operation.
Device Specifications and Features