Extreme Networks ExtremeWare XOS 11.1, Руководство пользователя

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ExtremeWare XOS 11.1 Concepts Guide
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DHCP Dynamic Host Configuration Protocol. DHCP allows network
administrators to centrally manage and automate the assignment of IP
addresses on the corporate network. DHCP sends a new IP address
when a computer is plugged into a different place in the network. The
protocol supports static or dynamic IP addresses and can dynamically
reconfigure networks in which there are more computers than there
are available IP addresses.
DiffServ Differentiated Services. Defined in RFC 2474 and 2475, DiffServ is an
architecture for implementing scalable service differentiation in the
Internet. Each IP header has a DiffServ (DS) field, formerly known as
the Type of Service (TOS) field. The value in this field defines the QoS
priority the packet will have throughout the network by dictating the
forwarding treatment given to the packet at each node. DiffServ is a
flexible architecture that allows for either end-to-end QoS or
intradomain QoS by implementing complex classification and
mapping functions at the network boundary or access points. In the
Extreme Networks implementation, you can configure the desired QoS
by replacing or mapping the values in the DS field to egress queues
that are assigned varying priorities and bandwidths.
DR Designated router. In OSPF, the DR generates an LSA for the
multiaccess network and has other special responsibilities in the
running of the protocol. The DR is elected by the OSPF protocol.
dropped packets These are packets that the switch received but does not transmit.
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EAPS Extreme Automatic Protection Switching. EAPS is an Extreme
Networks-proprietary protocol that prevents looping Layer 2 of the
network. This feature is discussed in RFC 3619.
EAPS domain An EAPS domain consists of a series of switches, or nodes, that
comprise a single ring in a network. An EAPS domain consists of a
master node and transit nodes. The master node consists of one
primary and one secondary port. EAPS operates by declaring an EAPS
domain on a single ring.
EBGP Exterior Border Gateway Protocol. EBGP is a protocol in the IP suite
designed to exchange network reachability information with BGP
systems in other ASs. EBGP works between different ASs.
ECMP Equal Cost Multi Paths. In OSPF, this routing algorithm distributes
network traffic across multiple high-bandwidth links to increase
performance. The Extreme Networks OSPF implementation supports
multiple equal cost paths between points and divides traffic evenly
among the available paths. As many as four links may be involved in
an ECMP link, and traffic is shared on the basis of IP source/
destination address session.
edge ports In STP, edge ports connect to non-STP devices such as routers,
endstations, and other hosts.
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