MES1000, MES2000 Ethernet Switches
11
Flow control
(IEEE 802.3X)
Flow control allows to interconnect the low-speed and the high-speed devices. To
avoid buffer overrun, the low-speed device gains the ability to send PAUSE
packets, that will force the high-speed device to pause the packet transmission.
Operation in device
stack
You can combine multiple switches in a stack. In this case, switches are considered
as a single device with shared settings. There are two stack topologies—ring and
chain. At that, all port parameters for all stacked devices could be configured from
the 'master' switch. Device stacking allows to reduce network management
efforts.
2.2.2
MAC Address Processing Functions
Table 2.2 lists MAC address processing functions.
Table 2.2 —MAC address processing functions
MAC address
table
The switch creates a look-up table for MAC addresses and switch port nodes in its
memory.
Learning mode
When learning is not available, the data, coming to any port, will be transmitted to
other ports of the switch. In learning mode, the switch performs analysis of the
frame, discovers sender's MAC address and adds it to the routing table.
Afterwards, the inbound frame, dedicated to the host, which MAC address has
been already added to the routing table, will be sent only to the port specified in
the table.
MAC Multicast Support
This function allows to perform one-to-many or many-to-many data distribution.
Thus, the frame addressed to the multicast group will be transmitted to each port
of the group.
Automatic Aging for
MAC Addresses
If there are no packets from the device with the specific MAC address in the
definite period of time, the record for this address expires and will be removed. It
allows to keep the switch table up to date.
Static MAC Entries
Network switch allows you to define static records of MAC address matches, that
will be saved to the routing table.
2.2.3
Second-layer functions of OSI model
Table 2.3 lists second-layer functions and special aspects (OSI Layer 2).
Table 2.3 —Second-layer functions description (OSI Layer 2)
VLAN support
The switches support VLAN operation.
Function
IGMP Snooping
IGMP protocol implementation analyzes the contents of IGMP packets and allows
to discover network devices participating in multicast groups and forward the
traffic to the corresponding ports.
MLD Snooping
MLD Snooping function implementation allows the device to minimize multicast
IPv6 traffic.
Function
Multicast-TV VLAN
Function that allows to redirect multicast traffic from the specified VLAN
(multicast VLAN) to the user port using IGMP messages and to reduce the load to
the uplink port of the switch. This function is used in III-play solutions.
Broadcast Storm Control
Broadcast storm is a multiplication of broadcast messages in each host causing
their exponential growth, that can lead to a network meltdown. Devices has a
function that restricts the transfer rate for multicast and broadcast frames
