This object configures how TSs will be compacted over the SHDSL Line. In both mapping cases (2),(3), only the TSs connected on the E1 line will be transferred over the SHDSL Line noCompaction - the whole E1 BW is reserved on the SHDSL Line, even if only part of the TSs are actually connected. noMapping - there is no mapping between the E1 TSs and the SHDSL frame TSs. Therefore, E1 connected TSs are ordered in ascending order (e.g E1 TSs 2, 16, 20 will occupy places 1, 2, 3 in SHDSL Line). In this case, if user wants to add connection for a TS that is lower than the existing ones on SHDSL, the TSs that are higher will have to move. That causes breaks in service for the moved TSs. (e.g if E1 TS8 is added in the above case, TSs 16 and 20 will move, so that by the end of this process, the E1 TSs 2, 8, 16, 20 will be ordered in SHDSL frame as 1, 2, 3, 4). withMapping - there is a mapping between the E1 TSs and the SHDSL frame TSs. Therefore, if some TSs were connected and then user wants to add additional E1 TSs, there is no need to move the existing TSs of the SHDSL frame. The additional TSs will be added AFTER the existing ones, or in gaps created by E1 TSs removed by user. The main thing is that the existing TSs will NOT be moved and so, their service will not be damaged by the addition or removal of E1 TS connections. lowTsMapping - the first 2 TSs are used for Signaling (TS16) and Dedicated TS if relevant. The payload starts afterwards, unmapped (according to E1 connected TSs order). This will ensure that Signaling and Dedicated TS will continue to function also when new TSs are connected. User will still get service breaks when TSs are moved. spareMapping - applicable only for MP-2100/2104 cards. It should be selected only when working vs. a MP-2100.2104. It resembles the noMapping option, but it contains Spare TSs for unconnected TSs. These Spare TSs will prevent service breaks upon added connections, because these will be selected from the Spare existing TSs.