MSM
This Extreme Networks-proprietary name refers to the module that holds both the control plane and
the switch fabric for switches that run the ExtremeXOS software on modular switches. One MSM is
required for switch operation; adding an additional MSM increases reliability and throughput. Each MSM
has two CPUs. The MSM has LEDs as well as a console port, management port, modem port, and
compact flash; it may have data ports as well. The MSM is responsible for upper-layer protocol
processing and system management functions. When you save the switch configuration, it is saved to
all MSMs.
MSTI
Multiple Spanning Tree Instances control the topology inside an
MSTP (Multiple Spanning Tree Protocol)
region. An MSTI is a spanning tree domain that operates within a region and is bounded by that region;
and MSTI does not exchange
BPDU (Bridge Protocol Data Unit)
s or send notifications to other regions.
You can map multiple
s to an MSTI; however, each VLAN can belong to only one
MSTI. You can configure up to 64 MSTIs in an MSTP region.
MSTP
Multiple Spanning Tree Protocol, based on IEEE 802.1Q-2003 (formerly known as IEEE 892.1s), allows
you to bundle multiple VLANs into one
topology, which also provides
enhanced loop protection and better scaling. MSTP uses
RSTP (Rapid Spanning Tree Protocol)
as the
converging algorithm and is compatible with legacy STP protocols.
MTU
A Maximum Transmission Unit is a configurable parameter that determines the largest packet than can
be transmitted by an IP interface (without the packet needing to be broken down into smaller units).
Note
Packets that are larger than the configured MTU size are dropped at the ingress port. Or, if
configured to do so, the system can fragment the IPv4 packets and reassemble them at the
receiving end.
NAT
The Network Address Translation (or Translator) is a network capability that enables a group of
computers to dynamically share a single incoming IP address. NAT takes the single incoming IP address
and creates a new IP address for each client computer on the network.
netmask
A netmask is a string of 0s and 1s that mask, or screen out, the network part of an IP address, so that
only the host computer part of the address remains. A frequently-used netmask is 255.255.255.0, used
for a Class C subnet (one with up to 255 host computers). The ".0" in the netmask allows the specific
host computer address to be visible.
NTP
Network Time Protocol is an Internet standard protocol (built on top of TCP/IP) that assures accurate
synchronization to the millisecond of computer clock times in a network of computers. Based on UTC,
NTP synchronizes client workstation clocks to the U.S. Naval Observatory Master Clocks in Washington,
DC and Colorado Springs, CO. Running as a continuous background client program on a computer, NTP
sends periodic time requests to servers, obtaining server time stamps and using them to adjust the
client's clock. (RFC 1305)
Glossary
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