Chapter 6. Configuration
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.
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