Appendix C:
Glossary
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LOC
LOC is an acronym for
L
oss
O
f
C
onnectivity and is detected by a MEP and is indicating lost
connectivity in the network. Can be used as a switch criteria by EPS
M
MAC Table
Switching of frames is based upon the DMAC address contained in the frame. The switch
builds up a 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 has been seen after a
configurable age time.
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.
MSTP
In 2002, the IEEE introduced an evolution of RSTP: the
M
ultiple
S
panning
T
ree
P
rotocol. The
MSTP protocol provides for multiple spanning tree instances, while ensuring RSTP and STP
compatibility. The standard was originally defined by IEEE 802.1s, but was later incorporated
in IEEE 802.1D-2005.
