1. Virtual Signaling Transfer Point User Guide
  2. vSTP Features
  3. SLS Rotation
  4. Use of Other CIC Bit

2.12.2 Use of Other CIC Bit

If the Use of Other CIC Bit option is selected, then vSTP derives SLS as per the following rule:

  • The bits at positions 2 to 4 of the CIC serve as three lower bits of SLS.
  • The Most Significant Bit (MSB) of SLS can be any bit from the bits at position 5 to 16 of the CIC.

This option can be used as a solution to the problem of vSTP not sharing load between all links within a linkset. It is applicable to ITU ISUP messages.

The Use of Other CIC Bit option applies to all ITU ISUP MSUs based on the combination of slsocbEnabled and slsocbit parameters. User needs to set the value of the slsocbEnabled parameter in m3rloptions MO to true and configure slsocbit in Linkset MO to specify the bit (bits at position 5 through 16 of CIC) to be used as the other CIC bit . The specified bit acts as the MSB of the new SLS and bits at position 2 through 4 of the received CIC become the LSBs of the new SLS. Once the SLS is generated, the existing algorithm for selecting a linkset and signaling link is performed and message is sent out on the selected link.

Use of Other CIC Bit Example:

The following figure shows an example of Use of Other CIC Bit

Figure 2-11 Example: SLS Use of Other CIC Bit


img/use_of_other_cic_bit_example.png