Octet String. Nibble No. 1 represents ON Hook (same for Rx and Tx). Nibble No. 2 represents OFF Hook (same for Rx and Tx). Nibble No. 3 represents Reverse Polarity. Nibble No. 4 represents Ring pattern 1. Nibble No. 5 represents Ring pattern 2. Nibble No. 6 is not used. The bits will be as following: Bit 1 = Bit A - ON Hook (LSB) Bit 2 = Bit B - ON Hook Bit 3 = Bit C - ON Hook Bit 4 = Bit D - ON Hook Bit 5 = Bit A - OFF Hook Bit 6 = Bit B - OFF Hook Bit 7 = Bit C - OFF Hook Bit 8 = Bit D - OFF Hook Bit 9 = Bit A - Reverse Polarity Bit 10 = Bit B - Reverse Polarity Bit 11 = Bit C - Reverse Polarity Bit 12 = Bit D - Reverse Polarity Bit 13 = Bit A - Ring 1 Bit 14 = Bit B - Ring 1 Bit 15 = Bit C - Ring 1 Bit 16 = Bit D - Ring 1 Bit 17 = Bit A - Ring 2 Bit 18 = Bit B - Ring 2 Bit 19 = Bit C - Ring 2 Bit 20 = Bit D - Ring 2 Bits 21...24 = 0 (not used). (Bit 24 is MSB). For Vmux-110: Ring 1 and Ring 2 are used. The default is 3 octets. (MSB) 0000 1011 1011 1001 1011 1010 (LSB)