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Maximum throughput of an ethernet network depends mainly on the number of users on the network, the capabilities of the network hardware, and the frame size.
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Standard considerations for utilization levels on an ethernet network are as follows : Light use is anything from 0% to 50% utilization; moderate to heavy use is anything from 50% to 80% utilization, and saturation occurs at 80% or higher consistent use.
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In a shared ethernet system, all hosts are connected to the segment and compete with one another for bandwidth.
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A switched ethernet system has one or more direct point-to-point connections between hosts or segments. Because of these direct connections, the hosts connected to the switched ethernet segment via a switch do not compete with each other for the available bandwidth.
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On ethernet networks, limit your shared ethernets to no more than 50% average utilization and 80% peak utilization. You should remain under 200 hosts per shared LAN segment.
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Hubs operate at the Physical layer of the OSI model (Layer 1). They are simple devices (no logic control) that join network segments and are invisible to all hosts on the network.
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Most switches operate at the Data Link layer of the OSI model (Layer 2). Layer 2 switches form a border for your collision domains.
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Some switches operate at the Network layer of the OSI model (Layer 3). Layer 3 switches form a border for your broadcast domains.
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Routers operate at the Network layer of the OSI model (Layer 3), moving IP or IPX packets to their destination addresses. Routers are also used to connect dissimilar physical networks, to connect WANs, and to segment LANs. Routers form a border for your broadcast domains.
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Full-duplex network communications effectively double the available bandwidth because the network traffic can be simultaneously transmitted and received at full wire speed on each transmit and receive path .
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Half-duplex network communications can transmit and receive only at separate times.
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Packet filtering checks all packets on the selected interface and can drop all packets not explicitly allowed.
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Packet filter allow and deny settings are called filter actions.
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Circuit-level filtering inspects all sessions on a particular interface.
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Protocol filtering checks the protocols in use on the selected interface and can drop any protocols that are not explicitly allowed.
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Demand-dial connections are point-to-point connections that generally are not active unless intentionally enabled, which makes them less susceptible to packet snooping.
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One-way initiated demand connections are normally configured so that one router is always the answering router and the other router is always the calling router.
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VPNs are network connections that are formed when a tunneling protocol is used to tunnel data over an existing network, such as the Internet or an intranet.
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Dial-up connections are network connections that are formed when a specifically enabled network device, such as a modem or an ISDN device, connects two devices over a Public Switched Telephone Network (PSTN).
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The Protected Extensible Authentication Protocol (PEAP) is available as an authentication method for 802.11 wireless clients, but it is not supported for VPN clients or other remote access clients . It can be used as an authentication method only when the Internet Authentication Service (IAS) is used.
