IP报文传输路径上有一系列的物理网络

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,Made by BJFU,InfoDepart,QiJd,Data Link Layer,Physical Layer,IP Layer,LLC,Ph,Lyaer,LLC,Ph Layer,MAC,WAN,LAN,Internet,Physical network,Based IP address,look for destination net-address for IP packet,Based on physical address,Frame transmission was done in every concrete physical network,Why address conversion required?,Address conversion Protocol:,ARP,Address Resolution Protocol,IP address,MAC address,RARP,Reserve Address Resolution Protocol,MAC address,IP address,How to convert?,Name resolve,IP,MAC Resolution Table,DNS,Conversion Schema in TCP/IP,IP communication process,Communication in the same IP,network(having,the same net-id),finished directly in Physical network,Communication in different IP,network(net,-id is different),pass to router for forwarding,Net1,Net2,R,ARP(RFC826),IP,报文传输路径上有一系列的物理网络,。,考查,IP,报文穿越任意一段物理网的过程：,假定其中一段为从,IP,A,IP,B,IP,A,把报文交给物理网时，需指明应送交物理网的,IP,B,站点,IP,B,站点取出报文递交到上层，即,IP,层,问题是：,IP,A,如何知道,IP,B,的物理地址是,MAC,B,?,（,IP,B,MAC,B,）,称为,地址绑定,如何根据,IP,B,找出,MAC,B,，,寻找过程称为,地址解析,IP packet,IP,A,IP,B,IP,A,IP,B,MAC,A,MAC,B,R,R,IP,A,IP,B,Details in IP transmission,IP packet,A,B,C,D,E,ARP Request,Full 1,MAC,C,0806,ARPreq(IP,B,0),FCS,ARP Response,MAC,C,MAC,B,0806,ARPresp(IP,B,MAC,B,),FCS,ARPresp,2,.B s ARP response,IP,A,IP,B,IP,C,IP,D,IP,E,MAC,A,MAC,B,MAC,D,MAC,E,IP,C,1,.C broadcast ARP request looking for,MAC,B,ARPreq,A,C,B,ARP Response,IP,08002B00EE0A,As ARP request,A receive Bs Response,Update Cache,IP MAC,202.114.0.225,08002B00EE0A,.,B receive,ARP,request,How to Update Address Resolution Table?,Ethernet,HostA,HostE,Hello everyone!I am 128.1.2.7,，,what is the MAC address for 128.1.2.15,？,Hi,128.1.2.7,，,I am 128.1.2.15 and my MAC address is 08:00:20:0e:28:ef,Listen/no reply,ARP address resolution table,of,HostA,IP MAC,-,128.1.2.7c0:a0:24:ec:c1:b4,128.1.2.11c0:20:c5:e2:c6:a2,128.1.2.15 08:00:20:0e:28:ef,How ARP Protocol work?,Listen/no reply,Listen/no reply,Listen/Reply,HwType,1=Ethernet,PrType,0800=IP,OP,1=ARP,Req,2=ARP,Resp,3=RARP,Req,4=RARP,Resp,HwType,PrType,HwLen,PrLen,OP,SrcHwAddress,（,1-4),SrcHwAddress,（,5-6),SrcIP,（,1-2),SrcIP,（,3-4),DstHwAddress,（,1,2),DstHwAddress,（,3-6),DstIP,HType,PType,HL,PL,OP,sMAC,sIP,dMAC,dIP,2 2 1 1 2 6 4 6 4,ARP Format,Hardware type=1,Protocol type=0800(IP),Length of hardware address=6 bytes,Length of protocol address=4 bytes,Opcode,1(ARP Request),Senders HD address=0:a0:24:ec:c1:b4,Senders IP address=128.1.2.7,Target HD address=?,Target IP address=128.1.2.15,Destination=,ff:ff:ff:ff:ff:ff,Source=0:a0:24:ec:c1:b4,Ethertype,=0806(ARP),ARP Request,ARP/RARP,Ethernet Header,FCS,Hardware type=1,Protocol type=0800(IP),Length of hardware address=6 bytes,Length of protocol address=4 bytes,Opcode,2(ARP Reply),Senders HD address=8:0:20:e:28:ef,Senders IP address=128.1.2.15,Target HD address=0:a0:24:ec:c1:b4,Target IP address=128.1.2.7,ARP/RARP,Packet size=60 bytes,Destination=0:a0:24:ec:c1:b4,Source=8:0:20:e:28:ef,Ethertype,=0806(ARP),ARP Reply,Ethernet Header,FCS,