计算机网络网络协议.ppt

1、2020年10月11日8时13分,本部分要点,WHAT IS TCP/IP? TCP/IP COMPONENTS DHCP的基本概念与工作原理 安装和配置DHCP服务器,2020年10月11日8时13分,WHAT IS TCP/IP?,TCP/IP is a protocol that was originally developed by the Department of Defense.Basically, TCP/IP rovides a set of rules that govern how computers ommunicate with each other over a n

2、etwork. Just as people have to speak the same language to communicate with each other, computers must also communicate in the same language, or protocol.,2020年10月11日8时13分,WHAT IS TCP/IP?,TCP/IP 是一种协议,它最初是由美国国防部开发的。TCP/IP 提供了一组规则，用于在网络上多台计算机 之间相互通信。 就象人们必须讲同一种语言来相互交流一样，计算机之间也必须使用相同的语言或者相同的协议进行通信。,202

3、0年10月11日8时13分,WHAT IS TCP/IP?,TCP/IP is considered a suite of protocols because it is made up of many protocols that provide the vast communication functionality we now enjoy in networking environments and on the Internet. In fact, over 100 protocols are in the TCP/IP suite.,2020年10月11日8时13分,WHAT IS

4、 TCP/IP?,TCP/IP 可以看成是一簇协议，这是因为它是由许多协议构成，这些协议提供了网络环境和Internet上的大量通信功能。 实际上，在 TCP/IP suite中，包含100多个协议。,2020年10月11日8时13分,The following list points out some of the most common ones:,Transmission Control Protocol (TCP) provides connection-oriented communication.(传输控制协议，是提供面向连接的协议) Internet Protocol (IP)

5、manages routing and network traffic.(Internet协议，管理路由和网络流量） File Transfer Protocol (FTP) manages file transfer and remote directory management.（文件传输协议，管理文件传输和进行远程目录管理。）,2020年10月11日8时13分,The following list points out some of the most common ones:,Hypertext Transfer Protocol (HTTP) is the Internet stan

6、dard for the delivery of HTML documents.（超文本传输协议，是传送HTML文档的Internet标准） Simple Network Management Protocol (SNMP) manages network devices and monitors network events.（简单网络管理协议，管理网络设备和监测网络事件） Simple Mail Transfer Protocol (SMTP) provides messaging (e-mail) services.（简单邮件传输协议）,2020年10月11日8时13分,2020年10月

7、11日8时13分,User Datagram Protocol (UDP) provides connectionless communication.（用户数据报协议，提供无连接的通信） Network News Transfer Protocol (NNTP) provides0 newsgroup services.（网络新闻传输协议，提供新闻组服务） Telnet provides terminal emulation for remote connections.（提供远程连接的终端仿真。）,2020年10月11日8时13分,Address Resolution Protocol (

8、ARP) resolves IP address to hardware (MAC) addresses（地址解析协议,将IP地址解析为硬件MAC地址） Internet Control Management Protocol (ICMP) provides error control（提供错误控制） Lightweight Directory Access Protocol (LDAP) provides directory access capabilities（轻型目录访问协议,提供目录访问功能）,2020年10月11日8时13分,TCP/IP COMPONENTS,Just as a

9、language has certain components, such as words, grammar, and syntax, the TCP/IP protocol contains components that enable each computer on a TCP/IP network to function and communicate on the network. You must configure three major TCP/IP components on TCP/IP computers: the IP address, subnet mask, an

10、d default gateway.,2020年10月11日8时13分,IP address:,IP address: Each computer on a TCP/IP network must have a uniqueIP address. The IP address identifies that computer onthe network and the address must be unique A computers IP address enables the network todeliver communication to that particular compu

11、ter.,2020年10月11日8时13分,Each IP address is 32 bits long, and is divided into 4 bytes. Each byte is referred to as an octet. A typical IP addresses looks like this: 00. In order to understand IP addressing, you have to start thinking in binary math. Computers see data in terms of ones and ze

12、roes. In essence, a stream of network data is simply made up of ones and zeroes that the computer interprets. One (1) represents “on” and zero (0) represents “off.”,2020年10月11日8时13分,In binary math, the bits are added together to determine the numerical value. For example, if all bits in the octect a

13、re turned “on,” then the numerical value is 255. In other words, 11111111 in binary is equal to 128+64+32+16+4+2+1, which equals 255.,If all the bits are “off,” then the binary representation is 00000000 which is equal to 0+0+0+0+0+0+0+0, which equals 0. Using this scheme, you can represent any numb

14、er between 0 and 255.,2020年10月11日8时13分,For example, what is binary value of 10? Remember that the bits in the octet must be turned on or off to equal the number ten. In the binary octet, the number 10 is represented as 00001010, which equals 0+0+0+0+8+0+2+0, which equals 10.,An IP address is made up

15、 of four octets that are separated by periods. A typical IP address you may assign to a computer would be . In binary, the computers see this address as: 00001010 00000010 00000000 00000100,2020年10月11日8时13分,Network Computer,My IP address is Other computers on the network communicate

16、 with me by using this IP address. They see my IP address in binary, which is 00001010 00000010 00000000 00000100,2020年10月11日8时13分,Network Solutions:DHCP Server,Each IP address identifies both the network in which the computer (or node, such as a router) resides and the actual computer or node itsel

17、f. These are called the network ID and host ID. The three major groupings of IP addresses are called classes. The following list gives you an overview of the three classes:,2020年10月11日8时13分,Class A: Class A addresses have a beginning octet from 1 to 126. Network Solutions assigns the first octet and

18、 the network administrator assigns the three remaining octets. Class A networks were developed for large networks and obtaining a Class A address today is very difficult. Class A networks can support up to 16,387,064 hosts. Also, the address range of 127 is reserved for TCP/IP troubleshooting and is

19、 called a loopback address.,2020年10月11日8时13分,Class B: Class B networks have the first octet assignment from 128 to 191. Network Solutions assigns the first and second octet numbers and the network administrator assigns the last two. Class B networks can support up to 64,516 hosts.,2020年10月11日8时13分,C

20、lass C: Class C networks use 192 through 255 for the first octet. Network Solutions assigns the first three octets and the network administrator assigns the final octet. Class C networks can only support up to 254 hosts.,202.199.227,208,2020年10月11日8时13分,Subnet maskThe second component of IP addressing is the subnet mask.,Each IP address assigned to a client must include at least a default subnet mask. For Class A networks, the default subnet mask is . For Class B networks, the default s