points (digital, analogue, SIP, VoIP telephony systems and contact centres. Good understanding of IP version4 and voice communications infrastructure for all business units, diagnose connectivity, maintenance, assist points (digital, analogue, SIP, VoIP telephony systems and contact centres. Good understanding of IP version4 and voice communications infrastructure for all business units, diagnose connectivity, maintenance, assist points (digital, analogue, SIP, VoIP telephony systems and contact centres. Good understanding of IP version4