Final answer:
The specific characters from Mallory's narrative who exchanged rings are not clearly identified based on the provided information. Exchanges of rings in literature, such as in tales of the Knights of the Round Table, typically symbolize love or vows.
Step-by-step explanation:
The question appears to relate to characters within narratives from different sources; however, based on the information provided and considering the context of the narratives mentioned, it's not clear which specific characters exchanged rings in Thomas Malory's narrative.
In literature, such exchanges are symbolic, often of love or a pact between characters. Since specific details about Mallory's narrative or a direct reference to characters exchanging rings are not provided, it is challenging to supply a precise answer to this question.
However, discussing ring exchanges in literature, we might consider the tales of King Arthur and the Knights of the Round Table, where tokens like rings are often part of courtship or knightly vows.