What is the difference between an analogy and an extended metaphor?

Since these figures of speech are so similar, such that they are both a comparison of two things, it often causes distress.

A (extended) metaphor is usually a more simple comparison of objects, such as "A is B." The extension of the metaphor continues this trend by comparing numerous objects in the form of "A is B AND C is D." And extended metaphor can also follow the format of "A is B and C."

However, an analogy begins to be more complex in its structure. It begins to compare objects and show the relationship between them. Analogies usually take on the form of "A is to B just as C is to D".