There are millions of hosts on the Internet. In order to distinguish these hosts, people assign each host a special address called IP address. Each host can be accessed through an IP address. The IP address consists of four parts of numbers, each part corresponds to an 8-bit binary number, and the parts are separated by decimal points. For example, the IP address of a host is 211.152.65.112, and the Internet IP address is planned and managed by NIC (Internet Network Information Center). At the same time, Inter NIC, APNIC and RIPE are responsible for IP address allocation in the United States and other regions.

Fixed IP: A fixed IP address is an IP address assigned to a computer for a long time. Generally speaking, a special server has a fixed IP address.

Dynamic IP: Due to the shortage of IP address resources, users who access the Internet through telephone dialing or ordinary broadband generally do not have a fixed IP address, but an ISP dynamically assigns a temporary IP address. Ordinary people generally do not need to know the dynamic IP address, which is automatically completed by the computer system.

Internic (Internet Network Information Center) is responsible for the public address. These IP addresses are assigned to organizations that register and apply for Inter NIC. Access the internet directly through it.

Private addresses are unregistered addresses and are used exclusively for internal organizations.

The reserved internal private addresses are listed below.

Class a10.0.0-10.255.255.255

Class b:172.16.0.0-172.438+0.3336.

Class C:192.168.0.0-192.654438+068. 5668686

2. What organization assigned 2. IP address?

All IP addresses are assigned by NIC (Network Information Center), an international organization. At present, there are three such network information centers in the world.

Inter: responsible for the United States and other regions;

ENIC: responsible for Europe;

APNIC: responsible for the Asia-Pacific region.

China applied for an IP address through APNIC, which is headquartered in Tokyo University. When applying, you should consider what kind of IP address to apply for and then submit it to the domestic agency.

3. What are public and private addresses?

Internic (Internet Network Information Center) is responsible for the public address. These IP addresses are assigned to organizations that register and apply for Inter NIC. Access the internet directly through it.

Private addresses are unregistered addresses and are used exclusively for internal organizations.

The reserved internal private addresses are listed below.

Class a10.0.0-10.255.255.255

Class b:172.16.0.0-172.438+0.3336.

Class C:192.168.0.0-192.654438+068. 5668686

4. Why is it attacked by network?

According to the news of the Ministry of Public Security of China, in 2004, the national information network security survey and computer virus epidemic survey were successfully concluded. The survey shows that the computer virus infection rate of computer users in China is 87.9%, which is 2% higher than last year.

The survey shows that the computer virus infection rate of computer users in China is 87.9%, which is 2% higher than last year. However, the number of users infected with computer virus for more than three times decreased significantly, accounting for 57. 1% of all infected users, a decrease of 26% compared with last year, indicating that users' ability to prevent virus infection has improved.

From May 2003 to May 2004, the computer viruses with the highest infection rate in China were network worms and viruses or malicious codes targeting browsers, such as Shockwave, CyberSky, Nimda, SQL Worm and so on. The damage and loss caused by computer viruses have decreased compared with previous years, but the damage to the network has increased obviously, especially some computer viruses that steal sensitive information such as computer users' accounts and passwords are hidden and harmful.

The survey shows that the proportion of cyber security incidents in the surveyed units is 58%. Among them, 1 time accounts for 22% of the total, 2 times accounts for 13%, and more than 3 times accounts for 23%. In the network security incidents, the security incidents caused by computer viruses, worms and Trojans account for 79% of the total security incidents, 43% are network attacks such as denial of service, port scanning and tampering with web pages, and 36% are caused by large-scale spam. 54% of the surveyed units suffered slight losses due to network security incidents, and serious and very serious losses accounted for 10% of the total number of units where security incidents occurred.

The main reasons for network security incidents are that the security management system is not implemented and the awareness of security prevention is weak. Among them, 66% of security incidents are caused by reasons such as not patching and preventing software vulnerabilities. At the same time, the survey shows that information network users have paid more attention to safety management, implemented safety management measures and adopted special safety technology products. However, problems such as users' weak safety concept, lack of training for safety managers, lack of effective safety information reporting channels, and the development of safety service industry can not meet social needs are still outstanding.

The main reasons for network security incidents are that the security management system is not implemented and the awareness of security prevention is weak. Among them, 66% of security incidents are caused by reasons such as not patching and preventing software vulnerabilities. At the same time, the survey shows that information network users have paid more attention to safety management, implemented safety management measures and adopted special safety technology products. However, problems such as users' weak safety concept, lack of training for safety managers, lack of effective safety information reporting channels, and the development of safety service industry can not meet social needs are still outstanding.

5. How do individual users intercept network attacks?

Analysis of hacker attack characteristics and comprehensive analysis report of anti-attack technology

6. List of commonly used computer ports.

1 Transmission Control Protocol Port Service Multiplexer

2 compressnet management utility

3 compression process

5 Remote job login

7 Echo (echo)

9 discard

1 1 online users

13 time

15 network statistics

17 daily reference

18 message protocol

19 character generator

20 file transfer protocol (default data port)

2 1 file transfer protocol (control)

22 SSH remote login protocol

Remote login terminal emulation protocol

24 reserved for personal mail system

Smtp simple mail transfer protocol

Field Engineer of New South Wales User System

29 MSG ICP

3 1 message authentication

33 display support protocol

35 reserved for personal printer services

37 times

38 routing access protocol

39 resource location protocol

4 1 graphics

42 WINS host name service

Who is the nickname of the service?

44 MPM (Message Processing Module) Marking Protocol

45 message processing module

46 message processing module (default sending port)

47 nickel FTP

48 digital audio background service

49 TACACS login host protocol

50 remote mail inspection protocol

5 1 IMP (Interface Information Processor) Logical Address Maintenance

52 Xerox Network Service System Time Agreement

53 domain name server

Bill Exchange of Xerox Network Service System

55 ISI graphic language

Verification of Xerox Network Service System

57 Keep personal terminal access

58 Xerox network service system mail

59 Preserve personal file service

60 undefined

6 1 NI mail?

Asynchronous communication adapter service

63 WHOIS+

64 communication interface

65 TACACS database service

66 Oracle SQL*NET

Boot protocol server

68 boot protocol client

69 small file transfer protocol

70 information retrieval protocol

7 1 remote operation service

72 Remote job service

73 Remote operation service

Remote job service

75 reserved for personal dial-out service

76 Distributed External Object Storage

77 reserved for personal remote operation input service

78 modified TCP

79 Fingers (inquire about online users of remote hosts, etc.)

Hypertext Transfer Protocol of World Wide Web

8 1 host2 name service

82 means of transport

83 modular intelligent terminal ML equipment

84 public tracking devices

85 modular intelligent terminal ML equipment

86 micro-focus programming language

87 reserved for personal terminal connections.

88 Kerberros security authentication system

89 SU/MIT terminal analog gateway

90 DNSIX security attribute marking diagram

9 1 MIT Dover spooling

92 network printing protocol

93 device control protocol

94 Tivoli object scheduling

95 pounds

96 Dixie protocol specification

97 Fast Remote Virtual File Protocol

98 TAC (Tokyo University Automatic Computer) News Protocol

10 1 usually from sri-nic.

102 iso-tsap

103 ISO mail

104 x400-snd

105 csnet-ns

109 post office

110ppop3 server (mailbox sending server)

1 1 1 port mapping or sunrpc

1 13 identity inquiry

1 15 sftp

1 17 path or uucp path

1 19 news server

12 1 BO jammerkilla

123 network time protocol (exp)

135 DCE endpoint resolution

137 NetBios-NS

NetBios of DGN

139 win98 *** shared resource port (NetBios-SSN)

143 IMAP mail

144 news-news

153 sgmp - sgmp

158 PCMAIL

16 1 snmp - snmp

162 SNMP- trap -snmp

170 network postscript

175 virtual machine network

194 Irc

3 15 load

400 Virtual Machine Network 0

443 security service

456 hacker paradise

500 sytek

5 12 execution

5 13 login

5 14 shell-cmd

5 15 printer spooling system

5 17 call

5 18 ntalk

520 euros

526 Rhythm-New Date

530 messenger-rpc

53 1 conference chat

532 Network News-Read News

533 network wall

540 uucp - uucpd 543 klogin

544 kshell

550 new-who-new-who

555 stealth spy (stage)

556 remotefs - rfs_server

600 Garcon

666 attacks FTP

750 kerberos - kdc

75 1 kerberos_master

754 krb_prop

888 Elrokin

100 1 muffler or WebEx

10/10 10 Doly trojan horse v 1.35

Dolly Troy

1024 Cyber Spy.698 (Yai)

1025

1033 cyber espionage

1042 Bla 1. 1

1047 intruder

1080 wingate

1 109 kpop

1243 1/7

1245 volts

1269 calf matrix

1433 Microsoft SQL Server database service

1492 FTP 99 CMP(back riffice。 FTP)

1509 streaming media server

1524 Ingerslock

1600 knife

1807 spy

198 1 shocked

1999 back door

Default port of 2000 black hole (Trojan horse)

The default port is 200 1 black hole (Trojan horse)

2023 Pass ripper

2053 knetd

2 140 deep throat. 10 or invalid

2283 rats

2565 Striker

Winklass 2583 2

280 1 phineas

3 129 master's tricks

3 150 deep throat 1.0

32 10 school bus

3389 Win2000 remote login port

4000 OICQ client

4567 file nail

4950 IcqTrojan

The UPNP service is started by default in 5000 WindowsXP.

5 190 ICQ query

532 1 Firehotcker

5400 BackConstruction 1.2 or BladeRunner

5550 Xtcp

5555 rmt - rmtd

5556 mtb - mtbd

Robot 5569

57 14 Wincrash3

5742 winchester street

6400 that thing

6669 vampire

Deep throat 6670

67 1 1 ziqi

67 13 ziqi

6767 NT remote controller

677 1 deep throat 3

6776 SubSeven

6883 delta source

6939 infusion

6969 uninvited guest

7306 Network Wizard (Trojan Horse)

7307 ProcSpy

7308 X spy

Default Port of Glacier 7626 (Trojan Horse)

7789 ICQKiller

8000 OICQ server

9400 InCommand

940 1 InCommand

9402 InCommand

9535 people

9536 w

9537 Munster

9872 Doomsday Gate

9875 Doomsday Gate

9989 InIkiller

10000 news

1000 1 queue

10002 Poker

10 167 Doomsday Gate

10607 coma

1 1000 senna spy trojan horse

1 1223 progenictroman

12076 Gjamer or MSH. 104b

12223 black? Keyboard recorder

12345 default port of network bus Trojan

12346 default port of network bus Trojan

1263 1 WhackJob。 NB 1.7

16969 priority

17300 Mine 2

200000Millennium II (girlfriend)

2000 1 Millennium second generation (girlfriend)

20034 Network Bus Professional Edition

2033 1 Bla

2 1554 girlfriend or Shi Windler 1.82

Prosia ke 22222

23456 evil Ftp or ugly FTP or WhackJob

27374 ziqi

inexplainable

30029 aoteroyan

30 100 network scope

30303 socket 23

30999 Kuang

3 1337 back riffice

3 1339 cyber espionage

3 1666 Bad luck buster

3 1787 chop a tack

Prosia ke 33333 Hao

Troy spirit 200 1 a

34324 TN or micro Telnet server

404 12 advertisement

4042 1 master missed the trick

40423 dashi amusement park

47878 Bird 2

No.50766, Foer or Shi Windler

5300 1 remote shutdown

54320 Rear Throttle 2000

5432 1 school bus 1.6

6 1466 remote control instruction

65,000 demons