COMSPHERE 3600 Series Data Service Units6-52 July 1999 3610-A2-GB91-90Table 6-14Port Speed Configuration Options for DSU with TDM*Prt1( 9.6): 9.6Next 64 56 48 38.4 32 28.8 19.2 18.8 18.0 16.8 14.412.0 9.6 9.2 8.4 7.2 4.8 4.4 4.0 2.4 2.0 1.2 Disab PrevPort 1 Speed. Primary data rate in kbps on Port 1. (Must be set to the same value in the remote DSU.)NOTE: Port Pairs (Ports 1 and 2, 3 and 4, or 5 and 6) can be configured to operate with any combination ofdata rates with the following exceptions:One Port of Pair Other Port of Pair18.8 Any rate except 9.2 or 4.49.2 Any rate except 18.8 or 4.44.4 Any rate except 18.8 or 9.264 to — Sets port primary speed to one of 18 operating rates.1.2 kbpsDisab — Sets port primary speed to 0 bps.Choosing a primary speed for Port 1 and pressing Next brings up the speed selection menu for Port 2.Continue selecting port speeds until the primary speeds for all six ports have been chosen. (The default forPorts 2—6 is Disab.)1Option Verification: For all ports, the DSU verifies that the sum of the individual port speeds does notexceed the primary aggregate speed set in the DSU’s Rate(Kbps) configuration option. If the sum of the portspeeds equals the primary aggregate rate, an underspeed port selection is required.Underspeed: DisabNext Disab Prt1 Prt2 Prt3 Prt4 Prt5 Prt6 PrevUnderspeed Port. Selects which port is run slightly underspeed to allow for in-band framing and in-bandsecondary channel transport, if used. If more than one port is active, including the in-band secondarychannel transport and the sum of the speeds (not included in the in-band secondary channel transport)equals the primary aggregate speed, then one synchronous port must run underspeed. The number of bitsper second used for in-band framing is 10. The in-band secondary channel transport speed is set in 2ndChan(bps) and, if used, includes the 10 bps in-band framing. A port used for asynchronous operation maynot be set for underspeed.NOTE: Underspeed cannot be used with 4.4, 9.2, and 18.8 kbps data rates.Disab — No port runs underspeed during primary operation.Prt1 to — Selected port runs underspeed during primary operation. Ports 3—6 do not appearPrt6 when a 2-port TDM/Flex is installed.Option Verification: The DSU verifies that an underspeed channel is selected if the sum of the port speedsequals the primary aggregate speed.1 Port speeds in DSD and FEP port-sharing groups are only counted once per group when calculating usedbandwidth.* Only appears when MUX Funct is set to TDM. Refer to Port Speed Configuration Options for DSU with MCMP(Table 6-15) if MUX Funct is set to MCMP.
