第一讲引论 一、计算机网络发展经历了三个时代: 1.以单计算机为中心的联机系统 2.计算机—计算机网络 3.网络体系结构的标准化

该章主要介绍局域网的有关概念，包括局域网的特点及构成、局域网的协议及特点、CSMA/CD协议、令牌环协议及应用、以太网网络组成、快速与高速以太网等。在了解局域网概念的基础上，掌握组网的方法。重点难点：局域网的特点及构成、局域网的协议及特点、CSMA/CD协议、令牌环协议及应用、以太网网络组成、快速与高速以太网

该章主要介绍TCP/IP协议族的主要内容。包括TCP/IP与OSI协议关系、TCP/IP各层特点及功能、DNS、SMTP、SNMP、RIP、TCP、UDP、IP、ARP、ICMP等功能及应用方法。目的是希望同学在了解TCP/IP简单工作原理的基础上，能够对网络进行管理。重点难点：TCP/IP与OSI协议关系；TCP/IP各层特点及功能；DNS、SMTP、SNMP、RIP的功能及应用；TCP、UDP、IP、ARP、ICMP的功能及应用；IP地址与子网掩码；路由表构成与应用；APR缓冲表构成与应用；网络接口层功能及应用

第五讲PC控制系统 一、所谓PC,是“个人计算机”的英文“Personal Computer缩写。一般特指美国IBM公司 Intel推出以的80X86为CPU的计算机,因此,也称为IBM-PC其前加“”是指工业测控专用(Industrial)PC相对一般的PC机,有如下改进特点:

Slide 12.1.1 In the last lecture, we introduced mutation as a component of 6001s|cP our data structures We saw for example that set was a Environment mode way of changing the value associated with a variable in our system, and we saw that set-car! and set-cdr! were ways of changing the values of parts of list structure Now, several important things happened when we introduced

The role of abstractions In this lecture, we are going to look at a very different style of creating large systems, a style called object oriented programming. This style focuses on breaking systems up in a different manner than those we have seen before To set the stage for this, we are first going to return to the notion of

Slide 14.4.1 Cleaning up some details of our implementation So we have seen a first pass at building an object-oriented tem, using Scheme as the base. There are a few details that The need for self-reference

Slide 15.6.1 The next stage in the evolution of our evaluator is to pull the 5. Environment as explicit parameter environment out as an explicit parameter. Up until now we could rely on just having a single environment in which to store (eva1'(pus*64)) bindings for variables. It made sense to have a global

Slide 16.1.1 Building up a language Last time, we completed building our evaluator. And as you saw, we slightly misled you. We started off saying we were going to user Scheme's lexical analyzer and parser, but then build our own evaluator, which we did initially for arithmetic

Slide 17.1.1 Normal Order(Lazy) Evaluation Over the past few lectures, we have been looking at evaluation especially how to implement eval and apply in a anguage such as Scheme, in order to define a language. What we have seen is that by creating, or specifying, eval and its associated procedures, we actually define the semantics of the