The multiplayer components are run from the Nintendo Wi-Fi Connection. On this network, each game has a unique Friend Code, which can be exchanged with others to meet in the Wi-Fi Club. In order for a player to connect with a friend online, they must each register the other in their own Pal Pad. Registering a friend requires knowing their name and Friend Code; however, the name entered does not need to match the friend's actual player character's name. Friends can be registered manually by entering their Friend Codes into the Pal Pad, or automatically by trading Pokémon with other players in the Union Room.
Besides registering friends, the Pal Pad can be used to list registered friends and read the player's own Friend Code. The player's Friend Code is obtained when connecting to any place in the game having a Wi-Fi compatible activity, such as a Pokémon Center or the Battle Tower for the first time. The Pal Pad also records how many times the player has traded, or how many times the player has won or lost against another player in a Wi-Fi battle. In Pokémon Platinum and Pokémon HeartGold and SoulSilver, the Pal Pad also records how many times the players has won through the Battle Frontier's facilities with a friend, as well as the number of times the players have played Wi-Fi Plaza Games together. The Pal Pad can register up to 32 friends.