利用SLIP协议拨号上网的整个过程

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Randy Lu

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Feb 9, 2012, 9:39:58 PM2/9/12
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大家好,我最近在看网络方面的一些资料,对SLIP链路层谢谢有一些小疑问,问题如下:
通过SLIP协议拨号上网时,本地主机是如何知道自己的IP地址?其整个流程是怎么样的?

Shuo Chen

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Feb 10, 2012, 2:28:46 AM2/10/12
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jinhu wang

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Feb 10, 2012, 3:04:23 AM2/10/12
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jinhu wang

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Feb 10, 2012, 3:08:17 AM2/10/12
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PPP includes a process for assigning Layer 3 attributes using network control protocols (NCPs).
The NCP used to assign IP addresses within a PPP connection is IP Control Protocol (IPCP).
IPCP is described in RFC 1332.
The separation between link establishment and IP address allocation makes it possible to figure
out who the subscriber is before deciding how to treat his session:  Either terminate the session
locally or tunnel the session to a wholesaler.  The domain name provided in the user’s
credentials enables automated service or ISP selection. This powerful aspect of PPP is a key
reason dictating why PPP will remain the predominant session protocol for providers that are
offering wholesale services to third party ISPs.

jinhu wang

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Feb 10, 2012, 3:31:05 AM2/10/12
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借这个话题引申一下unnumberred接口。路由器上,往往会考虑节省ip地址资源而将对外的以太端口设置成unnumbered接口,这样的接口的特点是没有自己的ip地址,它们会借用主机的或者主端口的ip地址工作。
把这样的接口跟ip协议栈对接往往会遇到mac地址如何获取的问题。这样的ip地址掩码往往是全f,也就是说这个子网只有一个ip地址,跟对端端口不在同一网络,从而导致了标准的ARP协议没法工作。于是不同的厂商会对这样的端口有不同的实现方式,有的厂商用固定的预留mac地址作为目标地址,有的厂商修改ARP协议以适应这一特殊场景,间接的导致了不同厂商的路由器通过unnumberred端口无法对接。

xiaomin lu

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Feb 10, 2012, 5:03:34 AM2/10/12
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SLIP也可以的,不过它是一种很老的拨号上网方式


2012/2/10 Shuo Chen <gian...@gmail.com>
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