I was involved in the team providing Network support to Orange' Platinum customer "ST Micro-electronics" and we were handling their LAN/WAN infrastructure. We used to take care of their routers, switches, firewalls, and any other kind of issues in their network,

Later on, they subscribed to devices like Packetshapers, Bluecoat servers, F5 devices, Intellisync servers so we used to perform vendor coordination to troubleshoot/devices if necessary. We used to to send Network efficiency reports, RCA reports for Critical outages, Solutions to take care of and Critical outages that might have occured in the past.
Also, we used to raise Change requests for any upgradation/migration from one site to another. This included coordination with other entities within our organisation/Vendor/Field Engineers so we used to be the central point of contact.