Enterasys csx400 安装指导
Chapter 2: About the CSX400
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CyberSWITCH CSX400 and CSX400-DC Installation Guide
The Designated Router is chosen from the list of eligible routers. If a one or more routers have
declared itself to be the DR in their Hello packets, the one with the highest Router Priority
becomes the DR. If no routers have declared themselves to be DR, then the router with the highest
priority becomes DR.
declared itself to be the DR in their Hello packets, the one with the highest Router Priority
becomes the DR. If no routers have declared themselves to be DR, then the router with the highest
priority becomes DR.
Backup Designated Router
Backup Designated Routers (BDR) are used for each multi-access network. The BDR is adjacent
to all routers on the network and becomes the Designated Router if the existing Designated Router
fails. The BDR does not generate network link advertisements and is also elected by the Hello
Protocol.
to all routers on the network and becomes the Designated Router if the existing Designated Router
fails. The BDR does not generate network link advertisements and is also elected by the Hello
Protocol.
The Backup Designated Router is chosen from those routers who have not declared themselves to
be the Designated Router. If a one or more routers have declared itself to be the BDR in their Hello
packets, the one with the highest Router Priority becomes the BDR. If no routers have declared
themselves to be BDR, then the router with the highest priority becomes BDR.
be the Designated Router. If a one or more routers have declared itself to be the BDR in their Hello
packets, the one with the highest Router Priority becomes the BDR. If no routers have declared
themselves to be BDR, then the router with the highest priority becomes BDR.
Detailed information on the OSPF protocol is documented in RFC 1247.
HDSL
High-bit rate Digital Subscriber Line (HDSL) technology uses existing copper twisted pair cables
designed for conventional analog voice transmission from a telephone carrier servicing area as a
low-cost alternative to the quality and speed of fiber optic cables, and provides high-speed
full-duplex digital transmission links of up to 1.544 Mbps. The WPIM-HDSL is easy to install in
your network over existing telephone lines, and it is a portable investment if a business, or
individual user plans to relocate.
designed for conventional analog voice transmission from a telephone carrier servicing area as a
low-cost alternative to the quality and speed of fiber optic cables, and provides high-speed
full-duplex digital transmission links of up to 1.544 Mbps. The WPIM-HDSL is easy to install in
your network over existing telephone lines, and it is a portable investment if a business, or
individual user plans to relocate.
HDSL is a direct connection technology that allows connections to be made for distances of up to
12,000 feet over 24 American Wire Gauge (AWG) unconditioned Twisted Pair wire. To obtain the
Full T1 line Rate of 1.544 Mbps, two wire pairs are necessary (four wires). If one pair of wires is
used (two wires), then data rates of 772 Kbps are supported, which is equivalent to one-half of a
T1 line.
12,000 feet over 24 American Wire Gauge (AWG) unconditioned Twisted Pair wire. To obtain the
Full T1 line Rate of 1.544 Mbps, two wire pairs are necessary (four wires). If one pair of wires is
used (two wires), then data rates of 772 Kbps are supported, which is equivalent to one-half of a
T1 line.