# 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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HLEN 4 TCP 4

UDP UDP TCP

TCP

TCP SYN SYN+ACK

ACK

SYN 1

TCP TCP

FIN FIN+ACK TCP ACK FIN

DHCP

DHCP /

Internet IP DHCP

1 IP

2

3 IP

4 DNS IP

DHCP RARP IP

1 RARP

RARP 2 RARP IP

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