Defoe, who has had two spells at Spurs, has scored five times in his last two games for the Black Cats, including a hat-trick in the midweek win at Swansea.
"A great player, a top goalscorer
His quality is great
It's not new for us," Pochettino said.
Spurs, seeking their own striker to relieve the goalscoring burden on Harry Kane, are aiming to respond from their midweek loss to Leicester against a side they beat 1-0 in September.
Since then Dick Advocaat has been replaced by Sam Allardyce and Pochettino can anticipate how the former West Ham boss will shape his side.
"He has time to improve in the way he wants to play, (it was) a long time ago that we played (at Sunderland)," the Spurs boss added.
"All the teams Allardyce has managed are very tough
(But) you need to be careful with all the opponents.
"Always in the Premier League games are very tough
We will expect another tough game against Sunderland."
Allardyce's sides have a reputation of being difficult to break down, particularly away from home.
Pochettino must be hoping for a repeat of the response from the prior defeat, to Newcastle, when Spurs went on a three-match winning run.
He recognises Spurs must get better in every area of the game.
"We need to improve in all areas and all aspects," he said.
"For me football is about a lot of things, not only one, because it's a collective effort, collective game
It's impossible to speak of only one thing."
Spurs are unchanged, with Ryan Mason (ankle), Clinton Njie (knee) and Alex Pritchard (ankle) absent.
Source : PA
Source: PA