Multitech RouteFinder MTASR2-203, User Manual, Page: 35 / 90

Chapter 4 - RouteFinder Software
MTASR2-203 35
WAN Port Setup
The WAN Port Setup dialog box allows you to configure various parameters for the WAN connections
including T1 Framing Format and line coding for WAN1, mode and connection method for WAN 2,
Backup port if WAN 2 is to be used for dial backup, and the Advanced tab. The three tabs labeled WAN
1(T1), WAN 2, and Backup Port are used to configure their respective ports, and the Advanced tab is
used to enable features for all three ports.
The Port Enable feature enables routing and bridging on the selected WAN port. The RouteFinder is
capable of dialing a backup number in case WAN 1(T1) looses its connection (i.e., carrier signal is
dropped). If WAN 1 needs backup, then WAN 2 is used for this purpose and cannot be used for routing.
When Needs Dial Backup is enabled (checked), the WAN 2 tab becomes inactive (grayed-out), and
the Backup Port tab becomes active. You must enter a dial backup number in the Backup Parameters
for WAN 1 group on the Backup Port tab.
WAN 1(T1) Configuration
The Mode group for the WAN 1(T1) link is always in synchronous mode. You must configure clocking
using the appropriate option. By default, External Clock is enabled. This means that the clocking will
be supplied by your T1 service provider. If Internal Clock is enabled, it means that the RouteFinder
will supply the clocking to the T1 facility. When Internal Clock is enabled (checked) you must also set
the Clock Speed. Use the drop-down list to select the Clock Speed for the WAN 1 port.
The T1 Framing Format group is used to match the T1 framing format to that of your T1 service
provider. The options include D4 framing (12 frames), a 193-bit frame format that uses the 193
rd
bit for
framing and signaling information; and, ESF – Extended Super Frame (ESF) framing (24 frames) that
provides Checksum (CRC) error detection and 4KHz Facility Data Link (FDL). The T1 Framing Format
information is provided by your T1 service provider.
The T1 Line Coding group is used to match the T1 Line Coding type to that of your T1 service
provider. AMI (Alternate Mark Inversion) line coding is a bipolar coding scheme in which successive
ones alternate in polarity to prevent a BiPolar Violation (BPV). A BPV occurs when two consecutive
ones are the same polarity. B8ZS (Binary 8 Zero Suppression) line coding is used to satisfy the ones
density requirements of the T1 carrier facilities, while also allowing clear channel data. Since the
system timing is recovered from the pulse width of the ones, it is important to ensure that there is an
adequate proportion of ones in the data stream. If the data stream contains more than eight
consecutive zeros – a condition that could disrupt system timing – B8ZS substitutes a predetermined
pattern for the zeros. This substitution intentionally causes a BPV to occur, alerting the unit on the
receiving end that a substitution has taken place.