User's Manual

3CC12426AAAA TQ BJA 01 Issue 01 - April 2001 - Draft 04 199/346

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The slots of a real cross-connection (following the creation phase: see § 4.12.5.3 – Creation of a cross-

connection) are colored in green.

Note: It is not mandatory to create cross-connections with consecutive time slots. In that case, you

must match the first group of TNT time slot with a group of NT time slot, and then match the

second group and so on.

Note: It is not possible to «cross» the links between TNT and NT time slots. Example on the above con-

figuration link between TNT-TS 10 and TNT-TS 3 not authirized.

4.12.1.7– Grooming

Several NTs can be fed from a single TNT board and a single E1 port. This is known as "grooming".

4.12.2– Leased lines X21

A X21 cross-connection is a link between a TNT board of the BS linked to the TDM network (or ATM if

the CES is used: see § 4.12.6 – Circuit emulation (CES)) and the NT terminal (X21 port) linked to the

user peripheral devices.

The maximum flow offered on an X21 link is 2 Mbps.