T-Mobile US CTO Neville Ray says the company’s modern core architecture makes it less critical for the wireless operator to move to a virtualized network like competitors AT&T and Verizon. In an exchange via Twitter, Ray said T-Mobile’s efficient and modern core makes software-defined networking (SDN) benefits “less material for us than for others.”

However, he added that there will be a key opportunity for SDN when it comes to 5G and network slicing.

Analyst William Ho with 556 Ventures added that because T-Mobile isn’t bogged down with legacy systems like AT&T and Verizon, the move to SDN isn’t as urgent.

T-Mobile was created in 2001 when parent company Deutsche Telekom purchased VoiceStream Wireless for $35 billion and renamed it T-Mobile USA. In 2012 the carrier modernized much of its network and deployed an evolved packet core (EPC) with the help of Nokia Siemens Networks.

Ray’s twitter exchange was part of the company’s efforts to bring attention to T-Mobile’s progress with its network. In a blog post last week, Ray said the company’s LTE network reached speeds of 979 Mb/s in its test lab by using carrier aggregation, 4x4 multiple-in multiple-out (MIMO), and an unreleased handset with 256 quadrature amplitude modulation (QAM).

He also said he expects T-Mobile to be the first U.S. network to commercially offer 1 Gb/s speeds.

Ray added that T-Mobile customers are benefiting from several LTE Advanced technologies including Voice over LTE (VoLTE), carrier aggregation, cooperative multipoint systems (CoMP), self-organizing networks (SON), and wireless charging.

Ray also hinted at T-Mobile’s plans for 5G, but details are still very vague. “We see 5G completely transforming the mobile Internet and delivering brilliant breakthroughs,” Ray said in the blog post.

Some of those breakthroughs include virtual reality and artificial intelligence. Ray also reiterated some of T-Mobile’s findings when it conducted 5G tests last fall with Ericsson, Samsung, and Nokia.

In the Ericsson test, which used an Ericsson radio and two-directional beam-steering antenna technology, T-Mobile was able to deliver multiple streams of 4K video at the same time, plus complete a voice call. The company also said it achieved throughput speeds of 12 Gb/s and latency of less than 2 milliseconds.