Hi,folks: In the current DNS based PCE discovery draft, we use NAPTR to lookup PCE service and query SRV record and AAA record for a DNS domain name. In the draft, we only uses NAPTR flags 'a','s', "replacement expression", "regular expression" is not used.
The S-NAPTR procedure i.e., the "Straightforward-NAPTR" procedure, is defined in IETF RFC 3958 and describes a Dynamic Delegation Discovery System (DDDS) application procedures on how to resolve a domain name, application service name, and application protocol dynamically to target server and port by using both NAPTR and SRV resource records. The S-NAPTR simplifies the use of NAPTR by limiting the NAPTR flags only to "a", "s" and "". Comparing with using NAPTR, S-NAPTR requires only a subset of NAPTR strictly bound to domain names, without making use of the REGEXP field of NAPTR and make client resolution process much more predictable and efficient since multiple levels of redirection by using the "" flag and REGEXP field may lead to a deep chaining of resource records over time in the DNS configuration. In addition, some sadi that S-NATPR enables DNS lookup of services by using resource names while NAPTR by domain name, when using resource name We don't need to follow domain name syntax. Therefore I think using resource name is more flexible than using domain name and it is better for this draft to base on S-NAPTR specification [RFC3958] instead of following NAPTR defined in RFC3403. Any comments or opinions? Regards! -Qin -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Monday, August 12, 2013 3:18 PM To: [email protected] Subject: I-D Action: draft-wu-pce-dns-pce-discovery-02.txt A New Internet-Draft is available from the on-line Internet-Drafts directories. Title : Path Computation Element (PCE) Discovery using Domain Name System(DNS) Author(s) : Qin Wu Dhruv Dhody Daniel King Diego R. Lopez Filename : draft-wu-pce-dns-pce-discovery-02.txt Pages : 18 Date : 2013-08-11 Abstract: Discovery of the Path Computation Element (PCE) within an IGP area or routing domain is possible using OSPF [RFC5088] and IS-IS [RFC5089]. However, in some deployment scenarios PCEs may not wish, or be able, to participate within the IGP process, therefore it would be beneficial for the Path Computation Client (PCC) (or other PCEs) to discover PCEs via an alternative mechanism to those proposed in [RFC5088] and [RFC5089]. This document specifies the requirements, use cases, procedures and extensions to support discovery via DNS for PCE. The IETF datatracker status page for this draft is: https://datatracker.ietf.org/doc/draft-wu-pce-dns-pce-discovery There's also a htmlized version available at: http://tools.ietf.org/html/draft-wu-pce-dns-pce-discovery-02 A diff from the previous version is available at: http://www.ietf.org/rfcdiff?url2=draft-wu-pce-dns-pce-discovery-02 Please note that it may take a couple of minutes from the time of submission until the htmlized version and diff are available at tools.ietf.org. Internet-Drafts are also available by anonymous FTP at: ftp://ftp.ietf.org/internet-drafts/ _______________________________________________ I-D-Announce mailing list [email protected] https://www.ietf.org/mailman/listinfo/i-d-announce Internet-Draft directories: http://www.ietf.org/shadow.html or ftp://ftp.ietf.org/ietf/1shadow-sites.txt _______________________________________________ Pce mailing list [email protected] https://www.ietf.org/mailman/listinfo/pce
