Practical TCP/IP Designing, using, and troubleshooting TCP/IP networks on Linux® and Windows

883 Pages·2008·5.23 MB·English

TCP and UDP port numbers
Below is a sub-set of the assigned port numbers. For a full list, see:
❑http://www.iana.org/assignments/port-numbers Port Numbers
7 Echo 119 Network News Transfer Protocol (NNTP)
9 Discard 123 Network Time Protocol (NTP)
13 Daytime 137 NetBIOS Name Service
19 Character Generator 138 NetBIOS Datagram Service
20 FTP – Data 139 NetBIOS Session Service
21 FTP – Control 143 Internet Message Access Protocol (IMAP)
22 SSH Remote Login Protocol 146 ISO-IP0
23 Telnet 147 ISO-IP
25 Simple Mail Transfer Protocol (SMTP) 161 SNMP
43 Who Is 162 SNMP trap
53 Domain Name Server (DNS) 257 Secure Electronic Transaction
67 Bootstrap Protocol and DHCP – Server 443 HTTP over TLS/SSL (HTTPS)
68 Bootstrap Protocol and DHCP – Client 445 Microsoft-DS
69 Trivial File Transfer Protocol (TFTP) 500 ISAKMP
70 Gopher 512 remote process execution (rexec) – TCP only
79 Finger 513 remote login (rlogin) – TCP only
80 World Wide Web (HTTP) 513 who’s logged on – UDP only
88 Kerberos 514 remote shell (rsh) – TCP only
109 Post Office Protocol – Version 2 (POP2) 514 Syslog – UDP only
110 Post Office Protocol – Version 3 (POP3) 515 LPD printing
111 SUN Remote Procedure Call (RPC) 531 chat
113 Authentication Service
Except where noted, both UDP and TCP port numbers are allocated.
532 readnews 1812, 1813 RADIUS, RADIUS Accounting
540, 541 uucpd, uucp-rlogin 1965 Tivoli NPM
546 DHCPv6 Client 2005 Oracle – UDP only
547 DHCPv6 Server 2049 NFS (Network File System)
565 whoami 2998 Real Secure
647 DHCP Failover 3020 CIFS
683 CORBA IIOP 3306 MySQL
684 CORBA IIOP SSL 3407 LDAP admin server port
847 DHCP Failover 2 5190–5193 AOL (America Online)
1011–1024 Reserved 5631–5632 pcANYWHERE
1024 NFS mount (UDP only) 6000–6063 X window system
1027 NFS mount (TCP only) 6346–6347 Gnutella
1214 KAZAA 7000 IRC server
1352 Lotus Notes 7100 X Font Service
1433 Microsoft-SQL-Server 8080 HTTP alternate port
1434 Microsoft-SQL-Monitor 10080 Amanda
1435 IBM CICS 18181–18185, OPSEC CVP, etc.
1503 MS NetMeeting 18187, 19191
1512 Windows Internet Name Service (WINS) 18241 Check Point RTM
1525 Oracle 26000 Quake
1649 kermit 33435 … traceroute
1718–1720 H.323 conferencing, MS NetMeeting 49152–65535 Dynamic and/or private ports

Practical TCP/IP

Practical TCP/IP
Designing,using,and troubleshooting
TCP/IP networks on Linux® and Windows®
Niall Mansfield
An imprint ofPearson Education
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First published in Great Britain in 2003
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Contents at a glance
Part 1 How and why packets move on the network 1
0 A quick introduction to TCP/IP 3
1 Thetcpdump packet sniffer – your eyes and ears on the network 15
2 How packets move on the local wire 27
3 Basic routing – how packets move from this network to another network
connected to it 59
4 IPaddressing and netmasks in detail 85
5 Routing in detail – controlling how and where packets pass in and out of
your networks 113
6 Routing in practice 149
7 The DNS– names instead of IPaddresses 181
8 The DNS (2) – how the servers work 205
9 Troubleshooting the DNS 245
Part 2 End-user and system applications 257
10 The TCP protocol;the applications layer and the telnetapplication 259
11 E-mail – SMTP and POP3 285
12 E-mail – MIME,IMAP;other mail systems 317
13 The etherealprotocol analyzer and ngreppacket sniffer 333
14 HTTP and the World Wide Web 353
15 UDP and other protocols 397
16 DHCP – automating your TCP/IPclient management 409
17 Other applications and their protocols 425
Part 3 Microsoft Windows® Networking on a TCP/IP network 465
18 MS-Windows Networking – introduction 467
19 Windows Networking – name resolution 493
20 Windows Networking – logon and domains 523
21 Windows Networking – browsing the network 555
22 Using Windows Networking 583
Part 4 Connecting to the Internet, and Internet security 595
23 Connecting your site to the Internet 597
24 Firewalls 625
25 Other security services 649
26 Dial-up networking and PPP 661
27 VPN – virtual private networking 691
Epilog 719
Appendices 721
Index 833
Contents
Preface xv
Acknowledgments xxiii
Part 1 How and why packets move on the network 1
0 A quick introduction to TCP/IP 3
0.1 To debug and understand your network, trace the packets 4
0.2 Networks can be easier than stand-alone machines 6
0.3 TCP/IP consists of separate building blocks 8
0.4 TCP/IP traffic is made up of packets 10
Summary 12
1 The tcpdumppacket sniffer – your eyes and ears on the network 15
1.1 How tcpdumpworks 16
1.2 How to run tcpdump 18
1.3 How to select just the packets you’re interested in 20
1.4 Common problems with tcpdump 22
Summary 24
2 How packets move on the local wire 27
2.1 IP address and netmask – how to get a packet to your machine 28
2.2 Netmask – the range of my directly connected network 30
2.3 Ethernet networking: moving packets along the local wire 32
2.4 ARP – how my machine finds the Ethernet address of your machine 34
2.5 Viewing and manipulating ARP entries 36
2.6 Using pingto generate test traffic between two machines 38
2.7 Lab – building the simplest network possible: hubs and cabling 40
2.8 Hubs v. switches 42
2.9 Lab – software configuration: Windows 44
2.10 Verifying your settings – Windows 46
2.11 Lab – software configuration: Linux® 48
2.12 Lab – building the simplest network possible: implement and test 50
2.13 How to diagnose a problem with your network: hop by hop and step by step 52
Summary 54
3 Basic routing – how packets move from this network to another network
connected to it 59
3.1 The fundamental IP routing decision 60
3.2 Telling a router to forward a packet 62