见识了楼上的风采却发现现实的自己还在楼下而无法自拔！

如题！

admin | 15:30 | 未分类 |评论 (0)
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about ip address

http://www.rfc-editor.org/rfc/rfc3330.txt

 Address Block             Present Use                       Reference
   ---------------------------------------------------------------------
   0.0.0.0/8            "This" Network                 [RFC1700, page 4]
   10.0.0.0/8           Private-Use Networks                   [RFC1918]
   14.0.0.0/8           Public-Data Networks         [RFC1700, page 181]
   24.0.0.0/8           Cable Television Networks                    --
   39.0.0.0/8           Reserved but subject
                           to allocation                       [RFC1797]
   127.0.0.0/8          Loopback                       [RFC1700, page 5]
   128.0.0.0/16         Reserved but subject
                           to allocation                             --
   169.254.0.0/16       Link Local                                   --
   172.16.0.0/12        Private-Use Networks                   [RFC1918]
   191.255.0.0/16       Reserved but subject
                           to allocation                             --
   192.0.0.0/24         Reserved but subject
                           to allocation                             --
   192.0.2.0/24         Test-Net
   192.88.99.0/24       6to4 Relay Anycast                     [RFC3068]
   192.168.0.0/16       Private-Use Networks                   [RFC1918]
   198.18.0.0/15        Network Interconnect
                           Device Benchmark Testing            [RFC2544]
   223.255.255.0/24     Reserved but subject
                           to allocation                             --
   224.0.0.0/4          Multicast                              [RFC3171]
   240.0.0.0/4          Reserved for Future Use        [RFC1700, page 4]
admin | 09:27 | Tech |评论 (1)
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常见接口

路由器的异步和同步串行接口–小知识

由ITAA gotolab 原创

本文以Cisco路由器为例，介绍了路由器上常用接口的类型、特点和应用场合。
　　1 EIA/TIA 232
　　EIA/TIA 232有时又被称作RS-232 C.RS（Recommended Standard）代表推荐标准（EIA制定的标准一般都被冠以”RS” ），232是标识号，C代表RS-232的最新一次修改。它是由是美国电子工业协会/电信工业协会（Electronic Industries Association / Telecommunications Industries Association，EIA/TIA）在1969年公布的通信协议标准。它最初主要用于近距离的DTE和DCE设备之间的通信。后来被广泛用于计算机的串行接口（COM1、COM2等）与终端或外设之间的近地连接标准。该标准在数据传输速率20K bps时，最长的通信距离为15米。该标准对应的国际标准是CCITT推荐的标准V.24.
　　这个标准对串行接口通信的有关问题，如电缆、接口的机械、电气特性、信号功能及传送过程特性进行了描述。

(全文…)

admin | 04:32 | 未分类 |评论 (1)
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Understanding SVI Autostate Exclude

To be “up/up,” a router VLAN interface must fulfill the following general conditions:

•The VLAN exists and is “active” on the VLAN database of the switch.

•The VLAN interface exists on the router and is not administratively down.

•At least one Layer 2 (access port or trunk) port exists, has a link “up” on this VLAN and is in spanning-tree forwarding state on the VLAN.

admin | 15:28 | Tech |评论 (0)
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