M

management daemon (mgd)

JUNOS software process responsible for managing all user access to the router.

Management Ethernet

Another name for the fxp0 interface that provides out-of-band access to the router.

Management Information Base (MIB)

Definition of an object that can be managed by SNMP.

mapping agent

A router used in an auto-RP multicast network to select the rendezvous point for all multicast group addresses. This information is then advertised to all other routers in the domain.

Martian address

Network address about which all information is ignored.

Martian routes

Network routes about which information is ignored. The JUNOS software doesn't allow Martian routes to reside in the inet.0 routing table.

Martian routes

Network routes about which information is ignored. The JUNOS software doesn't allow Martian routes to reside in the inet.0 routing table.

mask

See subnet mask.

master

The router in control of the OSPF database exchange during an adjacency formation.

match

A logical concept used in a routing policy or a firewall filter. It denotes the criteria used to find a route or IP packet before performing some action.

match type

JUNOS software syntax used in a route filter to better describe the routes that should match the policy term.

maximum transmission unit (MTU)

Limit on segment size for a network.

MBone

Internet multicast backbone. An interconnected set of subnetworks and routers that support the delivery of IP multicast traffic. The MBone is a virtual network that is layered on top of sections of the physical Internet.

mean time between failure (MTBF)

Measure of hardware component reliability.

mesh

Network topology in which devices are organized in a manageable, segmented manner with many, often redundant, interconnections between network nodes.

message aggregation

An extension to the RSVP specification that allows neighboring routers to bundle up to 30 RSVP messages into a single protocol packet.

Message Digest 5 (MD5)

A one-way hashing algorithm that produces a 128-bit hash. See also Secure Hash Algorithm (SHA-1).

midplane

Forms the rear of the PIC cage on M5 and M10 routers and the FPC card cage on M20, M40e, M160, and T640 platforms. Provides data transfer, power distribution, and signal connectivity.

Miscellaneous Control Subsystem (MCS)

On the M40e and M160 routers, provides control and monitoring functions for router components and SONET clocking for the router.

mobile network access subsystem (MAS)

GSN application subsystem that contains the access server.

mobile point-to-point control subsystem (MPS)

GSN application subsystem that controls all functionality associated with a particular connection.

mobile station

A mobile device, such as a cellular phone or a mobile personal digital assistant (PDA).

Mobile Station Integrated Services Digital Network Number (MSISDN)

Number that callers use to reach a mobile services subscriber.

Mobile Switching Center (MSC)

Provides origination and termination functions to calls from a mobile station user.

mobile transport subsystem (MTS)

GSN application subsystem that implements all the protocols used by the GSN.

multicast

Operation of sending network traffic from one network node to multiple network nodes.

multicast distribution tree

The data path between the sender (host) and the multicast group members (receiver or listener).

Multiple Exit Discriminator (MED)

Optional BGP path attribute consisting of a metric value that is used to determine the exit point to a destination when all other factors in determining the exit point are equal.

Multiprotocol BGP (MBGP)

An extension to BGP that allows you to exchange routing knowledge from multiple NLRI within and between BGP ASs.

Multiprotocol Label Switching (MPLS)

Mechanism for engineering network traffic patterns that functions by assigning to network packets short labels that describe how to forward them through the network. Also called label switching. See also traffic engineering.