Contents
ix
January 2005
Netmask
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B-4
Subnet Addressing
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B-5
Private IP Addresses
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B-7
Single IP Address Operation Using NAT
.......................................................................
B-8
MAC Addresses and Address Resolution Protocol
.................................................
B-9
Related Documents
.................................................................................................
B-9
Domain Name Server
..............................................................................................
B-9
IP Configuration by DHCP
...........................................................................................
B-10
Internet Security and Firewalls
....................................................................................
B-10
What is a Firewall?
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B-11
Stateful Packet Inspection
...............................................................................
B-11
Denial of Service Attack
..................................................................................
B-11
Ethernet Cabling
...........................................................................................................
B-11
Category 5 Cable Quality
......................................................................................
B-12
Inside Twisted Pair Cables
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B-13
Uplink Switches, Crossover Cables, and MDI/MDIX Switching
............................
B-14
Appendix C
Virtual Private Networking
What is a VPN?
.............................................................................................................
C-1
What Is IPSec and How Does It Work?
.........................................................................
C-2
IPSec Security Features
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C-2
IPSec Components
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C-2
Encapsulating Security Payload (ESP)
...................................................................
C-3
Authentication Header (AH)
....................................................................................
C-4
IKE Security Association
.........................................................................................
C-4
Mode
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C-5
Key Management
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C-6
Understand the Process Before You Begin
...................................................................
C-6
VPN Process Overview
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C-7
Network Interfaces and Addresses
.........................................................................
C-7
Interface Addressing
.........................................................................................
C-7
Firewalls
...........................................................................................................
C-8
VPN Tunnel Between Gateways
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C-8
VPNC IKE Security Parameters
..................................................................................
C-10
VPNC IKE Phase I Parameters
.............................................................................
C-10