Solar Communications has expanded its Solar SIP, Ethernet fibre and DSL offering following an agreement with TalkTalk Business.
The deal gives all Solar customers access to TalkTalk Business's next generation network and the services that overlay connectivity.
The new partnership also helps Solar to gain better visibility into customers' networks by using TalkTalk Business's provisioning, management and support portal.
The portal offers advanced diagnostic tools so Solar support staff can proactively spot issues and act quickly so they don't escalate.
Solar Communications' CEO John Whitty said: "This year is forecast as the crossover point from ISDN to SIP, so 2016 is the perfect time for an alliance with TalkTalk Business."
TalkTalk Business Director of Partners Alex Tempest added: "There is an increasing need for next generation voice and communications solutions to make businesses function successfully today.
"TalkTalk Business and Solar Communications both recognise that businesses need straightforward access to this broad range of services, backed up by knowledgeable customer services, to remain competitive in all industries."