Справочник Пользователя для Adtran 4120
Chapter 1. Understanding ISDN and the Express 4110/4120
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Express 4110/4120 User Manual
61200176L3-1
Ordering ISDN
When ordering ISDN from the telephone company, request EZ-ISDN 1
(Capability Package U) to ensure it is set up properly. EZ-ISDN 1 is rec-
ommended by the industry for most home office/small business applica-
tions. If this is not available from your service provider or you would like
more information regarding ordering ISDN, see the ADTRAN document
Ordering ISDN Service User Guide part number 60000.015-8 or contact your
telephone company for alternative line configurations. The Ordering
ISDN Service User Guide is available on the ADTRAN home page at http://
www.adtran.com
(Capability Package U) to ensure it is set up properly. EZ-ISDN 1 is rec-
ommended by the industry for most home office/small business applica-
tions. If this is not available from your service provider or you would like
more information regarding ordering ISDN, see the ADTRAN document
Ordering ISDN Service User Guide part number 60000.015-8 or contact your
telephone company for alternative line configurations. The Ordering
ISDN Service User Guide is available on the ADTRAN home page at http://
www.adtran.com
or by calling ADTRAN.
Interoperability
The Express 4110/4120 is standards based and uses PPP developed by
Internet Engineering Task Force (IETF). PPP provides a standard method
of transporting multiprotocol datagrams over point-to-point links. PPP is
widely accepted by many ISDN bridge/router manufacturers. The
Express 4110/4120 will negotiate Multilink PPP when connecting both B-
channels. The Bandwidth Allocation Protocol (BAP) may also negotiate,
which enhances the management of adding and removing a B-channel.
Data compression is also supported using LZS
Internet Engineering Task Force (IETF). PPP provides a standard method
of transporting multiprotocol datagrams over point-to-point links. PPP is
widely accepted by many ISDN bridge/router manufacturers. The
Express 4110/4120 will negotiate Multilink PPP when connecting both B-
channels. The Bandwidth Allocation Protocol (BAP) may also negotiate,
which enhances the management of adding and removing a B-channel.
Data compression is also supported using LZS
®
technology from hi/fn™.
Connecting to the Internet
Internet Service Providers (ISPs) assign an IP address to use when con-
nected to their service using PPP negotiation. This assignment is based
on the assumption that the user has an ISDN terminal adapter running
PPP async-to-sync conversion or another rate adaption where the PPP
negotiation is terminated inside the PC’s IP stack. However, if an ISDN-
Ethernet gateway device is used, the ISP must preassign the customer a
subnet which uses multiple IP addresses. This may result in a much
higher cost to the user.
nected to their service using PPP negotiation. This assignment is based
on the assumption that the user has an ISDN terminal adapter running
PPP async-to-sync conversion or another rate adaption where the PPP
negotiation is terminated inside the PC’s IP stack. However, if an ISDN-
Ethernet gateway device is used, the ISP must preassign the customer a
subnet which uses multiple IP addresses. This may result in a much
higher cost to the user.
The Express 4110/4120 permits the user to assign any IP addresses to the
unit and computers. Operations on the network can occur normally. In
fact, one B-channel can connect to the ISP using NAT while the other B-
channel connects to another “private” or “fake” network. All packets
transmitted or received over the ISP connection are translated. The
Express 4110/4120 keeps track of the computers that request services over
the Internet. A web server address can be assigned under the Configura-
unit and computers. Operations on the network can occur normally. In
fact, one B-channel can connect to the ISP using NAT while the other B-
channel connects to another “private” or “fake” network. All packets
transmitted or received over the ISP connection are translated. The
Express 4110/4120 keeps track of the computers that request services over
the Internet. A web server address can be assigned under the Configura-