Appendix B. Changes from RFC 2616
Servers are given more leeway in how they respond to a range request, in order to mitigate abuse by malicious (or just greedy) clients. (Section 3.1)
A weak validator cannot be used in a 206 response. (Section 4.1)
The Content-Range header field only has meaning when the status code explicitly defines its use. (Section 4.2)
This specification introduces a Range Unit Registry. (Section 5.1)
multipart/byteranges can consist of a single part. (Appendix A)