ADTRAN ISU 2x64, User Manual

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Chapter 6. Configuration
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ISU 2x64 Dual Port ISDN Service Unit User Manual 61200051L1-1D
Clear Channel
Clear channel provides the entire bearer channel to the DTE with-
out regard to data format or protocol. This provides a rate adap-
tation at or near the ISDN circuit rate. The primary usage for
Clear Channel in dial line mode is 56 kbps and 64 kbps synchro-
nous. It is useful when the DTE performs its own internal syn-
chronous protocol/rate adaptation or the ISU 2x64 is calling a 4-
wire Switched 56 DSU. In the leased line mode, clear channel can
provide synchronous bit rates of 56 kbps, 64 kbps, 112 kbps, and
128 kbps.
BONDING mode 1
The BONDING mode 1 protocol allows the ISU 2x64 to commu-
nicate at bit rates in excess of 64 kbps to a maximum of 128 kbps.
BONDING provides high-speed communication between ISU
2x64s, ISDN TE/TAs, and inverse multiplexing equipment sup-
porting the
BONDING protocol. The protocol allows for the use
of both synchronous and asynchronous bit rates. When the ISU
2x64 uses the
BONDING mode 1 protocol, it must make two sep-
arate ISDN phone calls to seize control of both ISDN bearer chan-
nels. The protocol corrects any delays existing between the two
bearer channels and presents a single high-speed data channel to
the DTE. For successful high-speed operation, both the near- and
far-end DCE need to be configured to use
BONDING mode 1
protocol. BONDING mode 1 protocol negotiation phase has
numerous timers to allow for transmission delays due to satellite
hops, international calls, etc. The timers may be adjusted if neces-
sary by entering into
BONDING mode 1 submenu. See Figure 6-
22 for the menu tree.