服务器评测
因工作需要，最近为笔记本配备了CDMA无线上网卡，从此网络无处不在~~~~
偶使用的是联通 CDMA 1X 世界风 USB接口的无线网卡，很小，比普通U盘宽一点，此网卡估计是联通找厂商专门OEM的，采用的是美国 Silicon Labs 生产的 CP2101/CP2102 芯片，在 Linux 下驱动很简单。
CP2102简介:该芯片的功能是实现USB 和UART格式间数据的转换. CP2102是全新的UART转USB的单芯片解决方案。该芯片集成了一个符合USB2.0标准的全速功能控制器、EEPROM、缓冲器、和带有调制解调器
对于Linux 2.6.18 的内核，需要配置的地方如下：
1. USB 支持肯定是要的
Device Drivers -> USB Support ->
<M> Support for Host-side USB
[*] USB device filesystem
<M> EHCI HCD (USB 2.0) support
<M> OHCI HCD support
<M> UHCI HCD (most Intel and VIA) support
<M> USB Modem (CDC ACM) support
USB Serial Converter support —>
<M> USB Serial Converter support
[*] USB Generic Serial Driver
<M> USB CP2101 UART Bridge Controller
<M> USB driver for GSM and CDMA modems
如果使用其他芯片的无线网卡，在这里将它们选上
2. PPP 模块
Device Drivers -> Network device support –>
<M> PPP (point-to-point protocol) support
[*] PPP multilink support (EXPERIMENTAL)
[*] PPP filtering
<M> PPP support for async serial ports
<M> PPP support for sync tty ports
<M> PPP Deflate compression
<M> PPP BSD-Compress compression
<M> PPP MPPE compression (encryption) (EXPERIMENTAL)
<M> PPP over Ethernet (EXPERIMENTAL) ~
如果内核已经包含上诉驱动，在插入USB网卡后，通过 dmesg 可以看到相应的网卡硬件信息
hub 2-0:1.0: state 7 ports 2 chg 0000 evt 0006
uhci_hcd 0000:00:1d.1: port 1 portsc 0c80,00
hub 2-0:1.0: over-current change on port 1
hub 2-0:1.0: trying to enable port power on non-switchable hub
uhci_hcd 0000:00:1d.1: port 2 portsc 0893,00
hub 2-0:1.0: over-current change on port 2
hub 2-0:1.0: trying to enable port power on non-switchable hub
hub 2-0:1.0: port 2, status 0101, change 0009, 12 Mb/s
hub 2-0:1.0: debounce: port 2: total 100ms stable 100ms status 0x101
usb 2-2: new full speed USB device using uhci_hcd and address 5
usb 2-2: default language 0x0409
usb 2-2: new device strings: Mfr=1, Product=2, SerialNumber=3
usb 2-2: Product: CP2102 USB to UART Bridge Controller
usb 2-2: Manufacturer: Silicon Labs
usb 2-2: SerialNumber: 0001
usb 2-2: uevent
usb 2-2: configuration #1 chosen from 1 choice
usb 2-2: adding 2-2:1.0 (config #1, interface 0)
usb 2-2:1.0: uevent
usbserial_generic 2-2:1.0: usb_probe_interface
usbserial_generic 2-2:1.0: usb_probe_interface – got id
cp2101 2-2:1.0: usb_probe_interface
cp2101 2-2:1.0: usb_probe_interface – got id
cp2101 2-2:1.0: cp2101 converter detected
usb 2-2: reset full speed USB device using uhci_hcd and address 5
usb 2-2: cp2101 converter now attached to ttyUSB0
drivers/usb/core/inode.c: creating file ‘005’
hub 2-0:1.0: state 7 ports 2 chg 0000 evt 0004
然后安装拨号程序 (ppp、wvdial)
创建拨号配置文件 /etc/wvdial.conf
[Modem0]
Modem = /dev/ttyUSB0
Baud = 230400
SetVolume = 0
Dial Command = ATDT
Init1 = ATZ
FlowControl = Hardware (CRTSCTS)
[Dialer cdma]
Username = CARD
Password = CARD
Phone = #777
Stupid Mode = 1
Inherits = Modem0
这个配置文件应该是联通通用的，拨号用户名和密码都是固定的，它的计费是通过插在USB网卡里面的SIM卡对应的手机号码来的。
注意：上面的 Baud （传输速率） 后面的值很重要，如果设置错误，将无法拨号，提示下面的错误：
–> Initializing modem.
–> Sending: ATZ
–> Sending: ATQ0
–> Re-Sending: ATZ
–> Modem not responding.
因为偶用的这个无线网卡的上网速率为 230.4Kbps （包装盒上面有），所以对应的 Baud 值应设为 230400，有的地方可能不同，根据情况适当调整即可，将上网速率 x 1000 即可
最后输入 wvdial cdma 开始拨号
# wvdial cdma
–> WvDial: Internet dialer version 1.54.0
–> Cannot get information for serial port.
–> Initializing modem.
–> Sending: ATZ
ATZ
OK
–> Modem initialized.
–> Sending: ATDT#777
–> Waiting for carrier.
ATDT#777
CONNECT
$DCON
$DCONTYPE:2,2
–> Carrier detected. Starting PPP immediately.
–> Starting pppd at Thu Jan 24 10:58:41 2008
–> pid of pppd: 4964
–> Using interface ppp0
–> Authentication (CHAP) started
–> Authentication (CHAP) successful
–> local IP address 220.203.36.20
–> remote IP address 220.192.136.5
–> primary DNS address 220.192.8.58
–> secondary DNS address 220.192.32.103
–> Script /etc/ppp/ip-up run successful
–> Default route Ok.
–> Nameserver (DNS) Ok.
–> Connected… Press Ctrl-C to disconnect
可以看到拨号成功了，哈哈~~~~ 享受无线上网的乐趣吧~~~
后记：
原以为很麻烦，没想到如此简单，呵呵~~~~ 还是老子那句话：
“世上事有难易乎？为之，则难者亦易矣，不为，则易者亦难矣。”
要是上网速度再快一点就好了，230.4Kbps 只能看看网页、聊聊天，真实下载速度只有 230.4/8 = 28 Kbyte/s 左右，要更快，估计要等 CDMA 2x/3x 或 3G了
