Sunday marks the centenary of the armistice that brought the end of World War I, and those who served and who have served in conflicts since are being commemorated in services across the country.

For retired Lieutenant-Colonel Anthony John, when the clock strikes 11am he will be honouring multiple generations of his family who have served in the Australian Defence Force past and present.

"My grandfather was a soldier in World War II and was in Papua New Guinea. When he came back he was wounded badly and he died soon after," he said.

"My father also joined the army and fought in Malaya and Vietnam. I was in the army for 30 years and went to Papua New Guinea, to Bougainville and also to the Middle East, serving in Afghanistan."

The military links in the family stretch even further. Lieutenant-Colonel John's wife is also involved with the army, as is his eldest son, while his second son is set to join the air force.

"There was also my mother's uncle. He was in Gallipoli and was killed there," Lieutenant-Colonel John said.

Despite the career paths members of his family made generations before him, he said there wasn't family pressure to enlist.

"I wasn't compelled by others to join. It was a decision that I made," he said.

"I saw it as a job and I joined the army, and it helped that I knew about it."

The Ainslie resident served as an operations officer during peacekeeping efforts in Bougainville in the late 1990s. There, he earned the Conspicuous Service Cross, which recognises outstanding devotion to duty, or outstanding application of exceptional skills, judgement or dedication, in non-warlike situations.

He was then deployed for seven months during the early stages of the war in Afghanistan in 2002.

Before he was deployed, Lieutenant-Colonel John said he knew largely what to expect having heard stories about life in conflict zones from his father.

"He was quite open about things, because at that point I was a professional soldier, and he knew it was important to hear the truths of what happened," he said.

On Sunday, his father's medals, which include a Military Cross received for his service in Vietnam, will be worn alongside Lieutenant-Colonel John's own.

Now retired from the armed forces, the army veteran said days like Remembrance Day carry extra significance.

"It certainly means a lot more to me now," he said.

"It gives me time to reflect. Because both my father and grandfather have passed, it's now a chance to think about what they had done and what their service meant to me."

This year he will be looking to the present while remembering the past, as he watches his son give an address for Remembrance Day before watching the ceremony at the Australian War Memorial.