3Com OFFICE CONNECT CABLE/DSL SECURE GATEWAY 3CR856-95, User Manual

Page: 75 / 102

75
Auto-IP Addressing
Network devices use automatic IP addressing if they are
configured to acquire an address using DHCP but are unable to
contact a DHCP server. Automatic IP addressing is a scheme
where devices allocate themselves an IP address at random from
the industry standard subnet of 169.254.x.x (with a subnet mask
of 255.255.0.0). If two devices allocate themselves the same
address, the conflict is detected and one of the devices allocates
itself a new address.
Automatic IP addressing support was introduced by Microsoft in
the Windows 98 operating system and is also supported in
Windows 2000.
Private IP Addresses
The following address ranges have been reserved by the Internet
Engineering Task Force (IETF) for private use:
■
10.0.0.0 – 10.255.255.255
■
172.16.0.0 – 172.31.255.255
■
192.168.0.0 – 192.168.255.255
The Gateway has a default subnet of 192.168.1.0 –
192.168.1.255. 3Com recommends that you use this subnet for
the LAN addresses of your first Gateway and subsequent ranges
(192.168.2.0 – 192.168.2.255) for the LAN range of other
Gateways that you will connect to by VPN.
dua08 569-5aaa02.bo o k Pag e 7 5 Thursday , No vem ber 7 , 2002 3:09 PM