|
|
| About
Level 2 Intelligent Switch |
| Q. |
What
is layer-2 switch ? |
|
A.
|
If the switching process is carried out based on MAC
address in Ethernet packets, the switch is called a
layer-2 switch.
|
| Q. |
What is the difference between
Intelligent Switch and dummy switch ? |
| A. |
Dummy switch is a simple switch.
It just transfers packets between connections. It can
not control and monitor traffic in the switch.
Intelligent Switch is a switch with lots of software function.
It can help the network administrator to configure and
manage the network. |
| Q. |
What is VLAN ? Does CeLAN's
Intelligent Switch support overlapped VLAN ? |
| A. |
VLAN is Virtual LAN. A Virtual
LAN is a collection of network nodes that share the same
collision domain regardless of their physical location
or connection point in the network. A VLAN serves as a
logical workgroup with no physical barriers, allowing
users to share information and resources as though located
on the same LAN. Because there is a PVID number to assign
the VLAN action of each connection port, CeLAN's Intelligent
Switch supports overlapped VLAN. |
| Q. |
What is the difference between
In-Band Management and Out-Band Management ? |
| A. |
If the management of the network
is from a station attached directly to the network, it
is In-Band Management. Telnet and Web-Browser management
interface are In-Band Management. If the management of
the network is from a station not attached to the network,
it is Out-Band Management. Console management interface
is Out-Band Management. |
| Q. |
What is IEEE 802.1Q ? |
| A. |
VLAN-Tagging - Defines Ethernet
frame tags which carry VLAN information. It allows switches
to assign end-stations to different VLANs, and defines
a standard way for VLANs to communicate across switched
networks. |
| Q. |
What is SNMP ? |
| A. |
SNMP is "Simple Network Management
Protocol". It is the application protocol offering network
management services in the Internet suite of protocols. |
| Q. |
What is IGMP ? How to setup
the IGMP function in CeLAN's Intelligent Switch? |
| A. |
IGMP is "Internet Group Management
Protocol". It is a protocol through which hosts can register
with their local router for multicast services. If there
is more than one multicast router on a given sub-network,
one of the routers is elected and assumes the responsibility
of keeping track of group membership. CeLAN's Intelligent
Switch supports the IGMP function. If you set it to "Active"
mode, the switch will send a query to get the IGMP information
from IGMP Host/Router. If you set it to "Passive" mode,
the switch will listen and save the IGMP information when
it gets it. You can monitor the IGMP from the "IP Multicast
Perspective" function. |
| Q. |
Does CeLAN's Intelligent Switch
support QoS function ? |
| A. |
If there is priority information
in the tag of Ethernet packet, CeLAN's Intelligent Switch
will read the priority information and put the packet
to some queue according to the priority. There are 4 queues
for every port. The QoS (Quality of Service) function
is carried out with this function. |
| Q. |
What is Spanning Tree Protocol
? Does CeLAN's Intelligent Switch support it ? |
| A. |
Spanning Tree Protocol is a technology
that checks your network for any loop. A loop can often
occur in complicated or back-up linked network systems.
Spanning-tree detects and directs data along the shortest
path, maximizing the performance and efficiency of the
network. CeLAN's Intelligent Switch supports this function. |
| Q. |
Can I upgrade the software
in CeLAN's Intelligent Switch ? |
| A. |
Yes. You can upgrade the software
by TFTP protocol from network or Kermit protocol from
Console port. If you upgrade by TFTP, you have to put
the new software file in the TFTP server and download
it from the Intelligent Switch. If you upgrade by Kermit,
you can send the new software file to the Intelligent
Switch from terminal program and receive it from the Intelligent
Switch. |
| Q. |
What is packet buffer ? Will
it affect the performance of a switch ? |
| A. |
Because CeLAN's switches are
designed with store-and-forward algorithm, these switches
need a buffer to store the incoming packet and the buffer
is called packet buffer. If the operation of the switching
controller is very high efficient, a small packet buffer
can also get a very good performance. |
| Q. |
What is port trunking ? |
| A. |
Port Trunking defines a network
link aggregation and trunking method which specifies how
to create a single high-speed logical link that combines
several low-speed physical links. CeLAN's Intelligent
Switch and EtherSW 2400F/ 1600F all support port trunking
function. |
