di ko madyadong na gets tanong mo. pero try ko sagutin.
tama ka mmsc ay for multi media messaging. new phones now use almost the same protocol in entering the gateway of a network. thats why most networks dito man o sa labas ng bansa you need 2 access points internet at mms for multi media messaging.
now you are asking why merong MMSC apn ko? magkasama yan eh. Part of the networks APN. it uses the same protocol but a different acces point kung baga bibili ka ng bagong aircon. tas me libreng airfesher. alangan namang hindi mo tatangapin.
MMSC is not a big player as far as connecting to the internet but most networks will provide it for mms purposes.
i love your question