Authors,   I have been asked to do a QA review of draft-ietf-idr-ext-opt-param-04.txt.       Summary:   The document is reasonably straight forward and is well written. I have a few comments below.     Comments:   Minor Issues:   1) Section 2, Protocol Extensions. You have labelled the existing Length and Type fields as 0xFF. I assume the meaning of the second is still 'Type' since that is what any implementation would reasonably interpret it as, and that is the registry you are using a code point from. So it might be better to say in the text above the figure at the top of page 3 that the length and type fields in [RFC4271] are set to 0xFF.   Also, you don't explicitly define what a receiver should do with the length field if the type is 0xFF. Does it ignore it, or does it check that it is 0xFF and treat the OPEN message as malformed if it is < 0xFF?   Since the document changes the procedures in RFC4271 for BGP Open optional parameters where length > 255, in that the original length field is no longer to be interpreted as the actual length, then I think you should mark this draft as 'Updates: 4271'.   2) Section 5: Security Extensions The security considerations section seems to be lacking detail and amounts to one line:  "This extension to BGP does not change the underlying security issues"  It might be worth being a little more explicit, or at least use wording similar to RFC5492, and saying that it does not  add any new security issues that are not inherent in BGP [RFC4272].          Regards   Matthew