Virgin, ntl Telewest confusion.
Once there were dozens of little cable companies, and for a while this was good...
Then came Cabletel, and Telewest, backed by big American banks, who between them acquired almost all of the cable companies, including the Independent Broadcasting Authority's privatised network - "National Transcommunications Limited" - Cabletel adopted their acronym as their new name ntl:).
The Broadcast network was sold off and turned into Arqiva. Telewest then bought ntl:, although they told the BBC, ntl: bought Telewest to avoid a contractual penalty, due to a change-of-ownership clause written into the agreement for UKTV, a joint venture with Telewest's Flextech content division. "ntl: Telewest" then bought into the Virgin brand, while acquiring virgin.net in the process. Thus creating the following:
Virgin Media - Internet, TV, Telephony, Mobile.
ntl:Telewest Business - Business data, and Telephony.
These two distinct entities are part of the "VirginMedia Group Of Companies".
As for this recent ADSL Radius issue, that's internal. The support is 3rd party vendor support, but that's common as hardware support partners are rarely internal unless the hardware was exclusively developed by the company.