Planet GS-5220 Series, User Manual, Page: 555 / 568

User’s Manual of GS-5220 LCD Series
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table that maps MAC addresses to switch ports for knowing which ports the frames should go to (based
upon the DMAC address in the frame). This table contains both static and dynamic entries. The static
entries are configured by the network administrator if the administrator wants to do a fixed mapping
between the DMAC address and switch ports.
The frames also contain a MAC address (SMAC address), which shows the MAC address of the
equipment sending the frame. The SMAC address is used by the switch to automatically update
the MAC table with these dynamic MAC addresses. Dynamic entries are removed from the MAC
table if no frame with the corresponding SMAC address have been seen after a configurable age
time.
MEP
MEP is an acronym for M aintenance E ntity E ndpoint and is an endpoint in a Maintenance Entity
Group (ITU-T Y.1731).
MD5
MD5 is an acronym for
M
essage-
D
igest algorithm
5
. MD5 is a message digest algorithm, used
cryptographic hash function with a 128-bit hash value. It was designed by Ron Rivest in 1991. MD5 is
officially defined in RFC 1321 - The MD5 Message-Digest Algorithm.
Mirroring
For debugging network problems or monitoring network traffic, the switch system can be configured to
mirror frames from multiple ports to a mirror port. (In this context, mirroring a frame is the same as
copying the frame.)
Both incoming (source) and outgoing (destination) frames can be mirrored to the mirror port.
MLD
MLD is an acronym for M ulticast L istener D iscovery for IPv6. MLD is used by IPv6 routers to discover
multicast listeners on a directly attached link, much as IGMP is used in IPv4. The protocol is embedded in
ICMPv6 instead of using a separate protocol.
MVR
Multicast VLAN Registration (MVR) is a protocol for Layer 2 (IP)-networks that enables multicast-traffic