3Com 3C888 - OfficeConnect Dual 56K LAN Modem Router, User Manual, Page: 22 / 168

22 C
HAPTER
2: D
UAL
56K LAN M
ODEM
F
UNCTIONALITY
D
ESCRIPTION
Wan Side: The Two
56K Modems
On the Wide Area Network (WAN) side of the Dual 56K LAN Modem, up to 25
users can share access to the WAN through use of the LAN Modem’s two internal
56K modems. When you configure the Dual 56K LAN Modem, you can choose
one of two ways to use two analog lines:
■
Two separate connections to different locations (one per analog line, or
“channel”)
■
One high-speed connection at a time, using Multilink Point-to-Point Protocol
(Multilink PPP) to combine the two analog channels into one.
For an explanation of Multilink PPP, refer to “Understanding Multilink PPP and
Other Line Usage Options” later in this chapter.
Once a WAN connection is established, up to 25 users can share the open
connection and access the same location simultaneously.
Using the Modem
Channels
When you use the Dual 56K LAN Modem for its most common WAN application,
dial-out remote access, you can configure up to four remote destination profiles,
referred to as
Service Providers. For each Service Provider that you configure,
you can choose whether to set up the connection as a single analog “channel”
connection, or as a Multilink-enabled connection.
If two or more Service Providers are set up in the LAN Modem, each as a single
channel connection, the following typical dial-out scenario becomes possible, as
shown in Figure 8.
Figure 8 Two Simultaneous Dial-out Connections to Two Different Remote Locations
Pe
ter
Gr
eg
OfficeConnect¤
Dual 56K LAN Modem
Public telephone
network
Remote Private
Network
Two analog lines
Internet
Greg
Peter
Greg’s PC
Marsha’s PC
Jan’s PC
Peter’s PC
From the Ed ge to t he He art of th e Ne two rk.
3 Com
Alert Power
Message
RD AA CD SD OH RD AA CD SD OH
OfficeConnect Dual 56k LAN Modem
1 TX COLL 2 3 4
LAN Status MODEM 2 MODEM 1