# Part-1
① OSI OSI OSI
② MAC IP③
OSPF
① HELLO②
③
④SPF⑤
STP
STP ① ID ② ③
ID ④ IDSTP ① ② ③
IP ?
IP 20IP IP
HSRP
HSRPHSRP
IP MAC IPMAC
RIP 1 2
①RIP-V1 RIP-V2 ②RIP-V1 RIP-V2③RIP-V2 RIP-V1
VLAN
① switchport mode access② switchport mode trunk③ no switchport
OSPF OSPF RIP
12 VLSM34 DR/BDR5 30 LSA
PPP
1 PPP Point-to-Point Protocol
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2 PPP
3 PPP LCP Link Control ProtocolNCP Network Control Protocol PAP Password Authentication Protocol CHAP Challenge-Handshake AuthenticationProtocol4
1 PPP LCPLCP
ConfigurePackets Configure-AckpacketLCP
22
packetspackets
PAP CHAP
3PPP 1
NCP NCP PPP IPIPCP PPP
51 PAPPAP NAS Network Access Server
PAPNAS
NAS PAP
2 - CHAPCHAP NAS
challenge IDarbitrarychallengestring MD5 one-way hashing
algorithm IDCHAP PAP
CHAPreplayattack CHAP
3 remote client impersonation
6 PPPPPP
IP PPP
PPP ADSLAsymmetrica lDigital Subscriber Loop PPP
PPPoE PPP over Ethernet PPPoA PPP over ATM Ethernet PPP
PPPoE PPPoE ADSLADSL ATM
Asynchronous Transfer Mode PPP
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PPPoA PPPoE ATM PPPoE
ATM
VLAN
VLAN MAC VLAN
TRUNK
TRUNK
VLAN TRUNK VLAN TRUNK VLAN
IEEE802.1Q ISL
?
STP CHANNEL
VLAN ?
① ② ③ ④
OSPF RIP
110 120 1
L2 Cache
CPU
VLAN
ACL
?
PC
VTP
VLAN Trunk Protocol VTP VLAN VLAN
VTP ?
STP STP
1 STP
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2 STP
ACL NAT NAT
ACL
1 ACL
2 ACL
3 ACL
4 ACL
NAT
IP
NAT NAT PAT
TCP/IP
TCP
ISO17799 BS7799
ISO17799
1 2 3 4 5
6 7 8 9 10.
Hub
Hub
SSL TCP
443
RIP OSPF
①RIP Internet
RIP OSPF Internet
RIP
②RIP OSPF
③RIP&OSPF 120 110
1 RIP 15 RIP 15
OSPF
2 OSPF VLSM RIP RIP IP
3 RIP
OSPF
IP
4 RIP OSPF
5 OSPF
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OSPFInternet
1234
RIPOSPF
1234
123
VLAN VPN OSI
VPN VLAN
VLAN Virtual Local Area Network
VLAN 2 VLAN MAC|IP VLAN
VLAN VLAN TRUNK Dot1Q ISL
VPN VirtualPrivateNetwork
VPNVPN PPTP L2TPVPN VPN PPTP L2TP
WindowsXP
1 ipconfig/all ip DNS2 ping DNS34 internet5
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6 ip mac
ip
3 CPU
/(10Mbit/s---100Mbit/s)
OSI TCP IP ?
ARP ?ARP IP MAC
PING ?ICMP
TCP UDP ?TCP Transmission Control Protocol
TCP
TCP UDP User Data Protocol TCP
UDP
&
1234
Distance Vector Routing Link-State Routing
RIP IGRP EIGRP & OSPF IS-IS
# Part-2
OSI Open System Interconnect
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TCP/IP Transmission Control Protocol/Internet Protocol /
OSI TCP/IPInternet TCP/IP
OSI OSI
ICMP ICMP Internet Control Message Protocol TCP/IP
IP
ICMP
TFTP Trivial File Transfer Protocol TCP/IP
HTTPHTTP
DHCP
IPIP
TCP UDPTCP IP
TCP UDP
UDP UDP
ARP1 ARP ARP IP
MAC 2 ARP IP MAC
ARP IP MAC IP
3 ARP IP IP IP
MAC ARP MAC ARP MAC
4 ARP IP MAC ARP ARP ARP
ARP ARP
DNS Domain Name SystemDNS DNS
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DNS DNS UDP 53.
HTTP SMTP IP
TCP UDP
TCP UDP
TCP TCP UDPTCP UDP
Windows
ipconfig TCP/IP ipconfig/all IPipconfig/release IPipconfig/renew DHCP IP netstat tasklisttaskkill
ftp / telnet
net
net share net user net use net servicesnet view
Window
Automatic Updates Plug and Play USB Remote Registry ServiceComputer Browser
MAC IP IP
IP IP
IP IP
IP
10.0.0.0 172.16. 172.31 192.168.0. 192.168.255
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TCP
A B 1 TCP A B B A
A B 2 B
A B A B
A B B A B A
A B A B
3
PSTN GSM CDMA
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FDM
TDM
CRC FCS CRC
1
1
2 ARQ 1 1
5 3 3
n n
WT<=2n -1
3 ARQ 1
n WR 2n /2
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PPP
ISP ISP ISP LCP PPP NCP
PC IP PC NCP IP LCP
1
2 MAC
CSMA/CD Token-passing
1 /2 3 4
CSMA/CD
/ 1 2
3
4
5
6
7
8 8-1 8-28-3
Jam 8-4 Jam
6 | 6 | 2 | 46 —— 1500 | FCS 4
NAT
1 IP
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IP 2 NAT IP+
IP+IP Internet IP
Internet 3 IP IP
A 10.0.0 .0 —— 10.255.255.255B 172.16.0.0 —— 172.31.255.255C 192.168.0.0 —— 192.168.255.255
VLAN1 VLAN VLAN
2 VLAN MAC IP 3 VLAN : | | VLAN | | | FCS
VLAN OSI
OSI IP IP
MAC VLANNAT ACL QoS
VLAN
TTL ping traceroute ifconfig netstat TTL TTL
TTL 0 TTL 0TTL
TTL TTL 0ping TTL TTLtraceroute TTL ifconfig TTL netstat TTL
Linux
IP &
CIDR
Linux route add default gw< IP> ”
5
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EGP IGP
IGPRIP OSPF
RIP
1 1 RIP 15 16
RIP RIP
30 RIP UDP RIP IP
RIP
OSPF
OSPF IP OSPF
EGP
/ HUB
ping12
IP 3 45 ping
IP ARPRARPICMPIGMP
IPv4IPv4 32bit
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0 1 1 0127.0.0.1 ping IP TCP/IP
IP IP &
RARP
IP IP RARP IP
MAC RARP MAC MAC IP
RARP
TCP TCP UDP
E1 V.24 V.35
PPP
# Part-3
OSI TCP/IP
OSI 7
TCP/IP 4
5
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IP
A 0 0~127B 10 128~191C 110 192~223D 1110 224~239
ARP
ARP ARP IP MACARP
IP MAC MACARP MAC ARP
IP IPARP IP IP
MAC IP ARPARP IP ARP
MAC ARPIP MAC ARP
ARP ARP
Repeater
RIP metric) 1515
OSPF
TCP UDP
UDPTCP
TCP
TCP ACK
www.baidu.com
http://www.baidu.com, baidu.com
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1 DNS www.baidu.com IP 220.181.27.48 IPHTTP 220.161.27.48
TCP2 HTTP 80
50005000 IP IP
3
4 IP MACARP ARP IP
IP
HTTP
GET URLPOSTPUT URLDELETE URL
HTTP POST GET
(1)Get Post(2)Get Action URL
URL(3)Get 2KB post(4) HTTP GET
GET
URL
TCP/IP
IP ICMP ARP RARPUDP TCPFTP Telenet DNS SMTP
POP3 HTTP
TCP UDP
TCP
1 FTP 21 FTPFTP
2 TelnetDOS BBS -
BBS 233 SMTP
-SMTP 25
4 POP3 SMTP POP3 POP3110 POP3 Fo-xmail Outlook
Web 163-
5 HTTP WebUDP
1 DNS IP DNS 532 SNMP 161
3 TFTP(Trival File Transfer Protocal) 69
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UDP
IP
1
IP 0
2
1
3
DA 00 0.0.0.0~127.255.255.255B 10 128.0.0.0~191.255.255.255; C 110 192.0.0.0~223.255.255.255D 1110 224.0.0.0~239.255.255.255 D
E 1111 240.0.0.0~255.255.255.255 E
Notice A,B,C D E4 255.255.255.255
IP
192.168.1.1/30192.168.1.5/30
Notice
5 0.0.0.0
IP RARP BOOTP DHCP IPIP 255.255.255.255
IP6
127.0.0.0/8127.0.0.17 A B C
(private address)A 10.0.0.0/8 10.0.0.0~10.255.255.255 B 172.16.0.0/12 172.16.0.0~172.31.255.255 C 192.168.0.0/16 192.168.0.0~192.168.255.255
NAT DHCP DNS
NAT
(NAT,Network AddressTranslation) (WAN)IP Internet
NAT lP
DHCP
Dynamic Host ConfigurationProtocol, DHCPUDP IP
DNS
DNS (Domain Name System)IP
IP
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IP
IP 20 90 IPABCDE ABC IP IP
IP IP
01
IP1 2 TTL 3 4
8IP n n
16 n0
ARP
IP IPIP ARP
IP MAC ARP RARP
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ARP IP IP
ARP IPARP IP
ICMP
IP IP ICMP
ICMP ICMPIP
ICMP ICMP IP
AS AS ASAS
RIP OSPFBGP
1234
TCP
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