Roman Danyliw has entered the following ballot position for draft-ietf-bfd-unsolicited-11: Discuss
When responding, please keep the subject line intact and reply to all email addresses included in the To and CC lines. (Feel free to cut this introductory paragraph, however.) Please refer to https://www.ietf.org/about/groups/iesg/statements/handling-ballot-positions/ for more information about how to handle DISCUSS and COMMENT positions. The document, along with other ballot positions, can be found here: https://datatracker.ietf.org/doc/draft-ietf-bfd-unsolicited/ ---------------------------------------------------------------------- DISCUSS: ---------------------------------------------------------------------- ** Section 7.1 Limit the feature to specific interfaces, and to single-hop BFD with "TTL=255" [RFC5082]. Section 2.2 of RFC5082 says “set the TTL on the protocol packets to 255 (the maximum possible for IP) and then reject any protocol packets that come in from configured peers that do NOT have an inbound TTL of 255”. Guidance on dropping the packets based on TTL in RFC5082 appears to be missing here. ** Section 7.1. The following considerations are inconsistent: -- “To mitigate such risks, the following measures are mandatory: … Apply "policy" to allow BFD packets only from certain subnets or hosts.” Editorially (not discuss but related), why is policy in quotes? Requiring this check conflicts with the less rigorous SHOULD in Section 2: “The source address of the BFD Control packet SHOULD be validated against expected routing protocol peer addresses on that interface.” -- “To mitigate such risks, the following measures are mandatory: … Use BFD authentication, see [RFC5880]. In some environments, e.g. when using an IXP, BFD authentication can not be used … If BFD authentication is used, the Meticulous Keyed SHA1 mechanism SHOULD be used.” The text first says using BFD authentication is mandatory, but then says it is not possible in certain environments. Later is states that “if BFD is used”, but the text already said it was mandatory. ---------------------------------------------------------------------- COMMENT: ---------------------------------------------------------------------- Thank you to Derek Atkins for the SECDIR review. ** Section 7.1 Meticulous Keyed SHA1 is a stated as a SHOULD. Is this intended to express a preference over MD5? If so, perhaps this needs to be restated that “SHA1 MUST be used if it is supported.” ** Section 7.2 * data nodes local-multiplier, desired-min-tx-interval, required- min-rx-interval and min-interval all impact the parameters of the unsolicited BFD IP single-hop sessions. Please explicitly state the impact of write options on these parameters
