7000 Series L3 Managed Switch Reference Manual for Software v1.0
Glossary
C-15
May 30, 2003 Beta Draft
MDI
Management Data Interface.
MDIO
Management Data Input/Output.
MDI/MDIX
In cable wiring, the concept of transmit and receive are from the perspective of the PC, which is wired as a
Media Dependant Interface (MDI). In MDI wiring, a PC transmits on pins 1 and 2. At the hub, switch,
router, or access point, the perspective is reversed, and the hub receives on pins 1 and 2. This wiring is
referred to as Media Dependant Interface - Crossover (MDI-X). See “Auto-negotiation” on page 3.
MIB
See “Management Information Base” on page 14.
MOSPF
See “Multicast OSPF” on page 15.
MPLS
See “Multi-Protocol Label Switching” on page 16.
Multicast Backbone
The MBONE is a virtual network. It is layered on top of portions of the physical Internet to support routing
of IP multicast packets since that function has not yet been integrated into many production routers. The
network is composed of islands that can directly support IP multicast, such as multicast LANs like Ethernet,
linked by virtual point-to-point links called "tunnels". The tunnel endpoints are typically workstation-class
machines having operating system support for IP multicast and running the "mrouted" multicast routing
daemon.
Multicasting
To transmit a message to specific recipients across a network. A simple example of multicasting is sending
an e-mail message to a mailing list. Teleconferencing and videoconferencing also use multicasting, but
require more robust protocols and networks. Standards are being developed to support multicasting over a
TCP/IP network such as the Internet. These standards, IP Multicast and Mbone, will allow users to easily
join multicast groups. Note that multicasting refers to sending a message to a select group whereas
broadcasting refers to sending a message to everyone connected to a network. The terms multicast and
narrowcast are often used interchangeably, although narrowcast usually refers to the business model whereas
multicast refers to the actual technology used to transmit the data.
Multicast OSPF
With a MOSPF specification, an IP Multicast packet is routed based both on the packet's source and its
multicast destination (commonly referred to as source/destination routing). As it is routed, the multicast
packet follows a shortest path to each multicast destination. During packet forwarding, any commonality of
Summary of Contents for ProSafe GSM7324
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