From NENA Knowledge Base

Diffserv is a quality of service mechanism for IP networks defined by the IETF. Diffserv is characterized by marking IP packets using a Codepoint and directing network devices to process packets using a "per-hop behavior" at each device based on those code points.

Relevant NENA Documents

NENA-STA-010, NENA i3 Standard for Next Generation 9-1-1