http://wenda.tianya.cn/wenda/thread?tid=787b6cdb104d6bd1&hl=zh-cn

yum  update
Loaded plugins: refresh-packagekit
Error: Cannot retrieve repository metadata (repomd.xml) for repository: InstallMedia. Please verify its path and try again


yum --disablerepo=InstallMedia update

rm /etc/yum.repos.d/Fedora-install-media.repo

yum  update
Loaded plugins: refresh-packagekit
Error: Cannot retrieve repository metadata (repomd.xml) for repository: InstallMedia. Please verify its path and try again


yum --disablerepo=InstallMedia update

1 System-view

进入系统，可以配置。

display version
system-view
port-security enable

#11b g interface

interface WLAN-BSS2

port-security port-mode psk
port-security tx-key-type 11key

port-security preshared-key pass-phrase 12345678

wlan service-template 2 crypto

ssid h3c-psk

authentication-method open-system

cipher-suite tkip

security-ie wpa

service-template enable

# physica interface
interface WLAN-Radio 1/0/2

service-template 2 interface WLAN-BSS 2

#maybe need to disable the connection of service-template 1 with interface WLAN-BSS 2
undo service-template 1

interface Vlan-interface1

ip address 192.168.6.102 255.255.255.0

ip route-static 0.0.0.0 0.0.0.0 192.168.6.1

display current-configuration

s

which, that 区别如下。as I had expected是作状语
它们所代替的先行词是事物的名词或代词，在从句中可作主语、宾语等，例如：
A prosperity which / that had never been seen before appears in the countryside.（which / that在句中作宾语）
The package (which / that) you are carrying is about to come unwrapped. (which / that在句中作宾语)
关系代词that和which 都可以指物，that 和Who 都可以指人，其用法区别：
1）不用that的情况
a) 在引导非限定性定语从句时
(错) The tree, that is four hundred years old, is very famous here.
b) 介词后不能用
We depend on the land from which we get our food.
c)多用who 的情况
①关系代词在从句中做主语
A friend who helps you in time of need is a real friend .
②先行词为those , people 时
Those who were either fools or unfit for their offices could not see the cloth .
③先行词为all, anyone , ones , one 指人时
One who doesn’t work hard will never succeed in his work .

XCP 目录：

/ns-allinone-2.33/ns-2.33/tcl/ex/xcp

 

1 cbrgen

ns cbrgen.tcl -type cbr -nn 10 -seed 1 -mc 8 -rate 4.0

 

ns cbrgen.tcl -type tcp -nn 25 -seed 0 -mc 20

 

mc 并发连接

 

2

 

#
# nodes: 10, max conn: 8, send rate: 0.25, seed: 1
#
#
# 1 connecting to 2 at time 2.5568388786897245
#
set udp_(0) [new Agent/UDP]
$ns_ attach-agent $node_(1) $udp_(0)
set null_(0) [new Agent/Null]
$ns_ attach-agent $node_(2) $null_(0)
set cbr_(0) [new Application/Traffic/CBR]
$cbr_(0) set packetSize_ 512
$cbr_(0) set interval_ 0.25
$cbr_(0) set random_ 1
$cbr_(0) set maxpkts_ 10000
$cbr_(0) attach-agent $udp_(0)
$ns_ connect $udp_(0) $null_(0)
$ns_ at 2.5568388786897245 '$cbr_(0) start'

 

/ns-2.33/indep-utils/cmu-scen-gen/setdest

 

1 setdest

usage:

<original 1999 CMU version (version 1)>
 /home/szq/ns-allinone-2.33/ns-2.33/indep-utils/cmu-scen-gen/setdest/setdest -v <1> -n <nodes> -p <pause time> -M <max speed>
  -t <simulation time> -x <max X> -y <max Y>

OR
<modified 2003 U.Michigan version (version 2)>
 /home/szq/ns-allinone-2.33/ns-2.33/indep-utils/cmu-scen-gen/setdest/setdest -v <2> -n <nodes> -s <speed type> -m <min speed> -M <max speed>
  -t <simulation time> -P <pause type> -p <pause time> -x <max X> -y <max Y>
  (Refer to the script files make-scen.csh and make-scen-steadystate.csh for detail.)

 

-s speed type

   1   uniform speed from min to max

   2 

1 The film I saw was not very funny.

    very , much

 

区别1：very

 1 下面四个句子在意思上有无差别，冠词用得对不对？

1)She's studying the history of Europe.  Y

2)She's studying history of Europe. N