Troubleshooting Procedures
50
D3CM1604V EMTA Cable Modem Administrator Manual
Connected. Your computer is properly connected to the EMTA or wired/wireless network,
but there is a problem between the EMTA and the Internet.
Disabled. Someone has manually disabled the NIC. To fix the problem, right-click the
adapter and click Enable.
Unplugged. Your computer cannot detect the connection to the EMTA.
Not connected. Your computer cannot connect to your wireless network.
Limited or no connectivity. Your computer is properly connected to the EMTA, but either the
EMTA is misconfigured or there is a problem between the EMTA and the Internet.
Figure
5-1. Examples of Connectivity Statuses for Microsoft Windows XP
Troubleshooting Configuration Problems
After confirming that your hardware is working properly, examine your networking
configuration to determine whether there is a misconfiguration of IP addresses, subnet
masks, EMTAs, or broadcast addresses. Common configuration problems can be caused by
misconfiguring newly connected or configured devices.
Determining Your IP Address
An IP address uniquely identifies computers and computing devices, such as the EMTA, on
a TCP/IP network. IP addresses are normally expressed in dotted-decimal format, with four
numbers (or “octets”) separated by periods, such as
10.1.10.1
.
For troubleshooting purposes, all the numbers in the IP addresses of your networked
devices must be consistent across the network. This means:
Ÿ
The first nine numbers (i.e., the first three octets) in the IP addresses are the same for all
the devices on the network.
Ÿ
The last three numbers (i.e., the last octet) in the IP addresses are different and not in
use by other devices on the network (assuming your subnet mask is
255.255.255.000
).
For example, if the IP address for the EMTA is
10.1.10.1
, the other devices on the network
must have an IP address whose:
Ÿ
First three octets are
10.1.10
.