C
H
A
P
T
E
R
4
Configuring Asynchronous
Connections with Modems
To successfully configure an asynchronous modem connection, the following must occur:
1
The modem itself must be configured to respond correctly to the telephone company
circuit.
2
The physical aspects of the router link to the modem must be correctly defined to
match the modem parameters.
3
The logical parameters must be established to provide a network-layer end-to-end
connection.
The modem must be configured so that it understands the signalling on both the telephone-
line side and the router-connection side. This information includes the line rate and the
number of bits used for data and other physical settings for the modem. The particulars for
the modem are discussed in the body of this chapter.
The second and third pieces of an asynchronous modem connection are configured on the
router and provide both physical and logical aspects for a connection. The physical
properties are configured on the line. These parameters include the line rate, the data link-
layer protocols supported on the line, and so on. These parameters are needed for the router
line to communicate with the attached modem.
The last piece of an asynchronous modem connection is configuring the logical information
on the router interface. The logical information includes the Layer 3 addresses, the
network-layer protocol, the authentication methods, and so forth.
How to Best Use This Chapter
By taking the following steps, you can make better use of your study time:
·
Keep your notes and answers for all your work with this book in one place for easy
reference.
·
Take the "Do I Know This Already?" quiz and write down your answers. Studies show
retention is significantly increased through writing facts and concepts down, even if
you never look at the information again.
·
Use the diagram in Figure 4-1 to guide you to the next step.