The encapsulation error described is known as 'runts.' These are packets that are smaller than the minimum allowed size for Ethernet frames, which is 64 bytes. Frames that are smaller than this threshold are considered illegal and are usually dropped by network devices because they are often a result of collisions or other issues. Giants are oversized packets, more than the maximum allowable bytes; whereas CRC errors are related to data corruption during the transmission. Encapsulation errors, more broadly, could indicate issues with how the payload is wrapped within the frame, but in this context, 'runts' specifically refers to undersized frames.