On 04/03/14 20:04, Tom Herbert wrote: > Hi, > > i posted a new version of GUE (Generic UDP Encpasulation). I > appreciate comments, however please bear in mind: > > 1) This is not just for network visualization,
We love to "visualize" networks too. "A picture is worth a thousand words" Most of what has been said about Geneve applies here too. The "security key" portion needs to go to SFC for definition where it belongs. The security meaning needs are real security use case and security assessment. Otherwise it is RFC 3514 just expanded to an arbitrarily large size of [do no] evil. Lots and Lots of "evil" bits aligned on a 32 bit boundary. Nice... In fact, I have a suggestion, chairs, can the "encapsulation du jour" fest be limited from now onwards and no encapsulation be admitted for discussion unless it has at least two interoperable implementations, preferably one for type 1 and one for type 2 hypervisors. Exemptions only for implementations which are universal across let's say nearly all Type 2 or nearly all Type 1s. Thanks in advance, A. > we anticipate other use > cases. Network virtualization is a very important use case. > 2) I do not claim that this solves all of the problems or addresses > all requirements of encapsulation or networking virtualization. As far > as I can tell, it does satisfy most of our needs for a generic and > ubiquitous encapsulation (in one large data center environment). Even > so, we still have need for other encapsulation protocols in different > contexts. > 3) Please take this as input for some requirements and potential > solutions when contemplating standard encap protocols. > 4) We did consider many alternate encapsulation protocols (see > motivation section). GRE was the closest to what we need, and in fact > the basic concepts of GUE are derived from GRE. GRE is very simple, > generic, stateless, allows for extensions, is amenable to efficient HW > implementation, and is suitable for high PPS applications. We can't > use directly GRE because adding new fields (extensibility) breaks > middleboxes which need to parse inner headers (header length ambiguity > with new fields). So in GUE we have a header length field that can > allow a device to skip over unknown options. Also, we chose to > encapsulate by IP protocol as opposed to the EtherType which is more > efficient and appropriate when doing L3oL3 encap (our majority use > case). > 6) GRE-like flag-fields are very limited and constrained compared to > something like TLVs which allow open ended extensibility. Their use > represents a trade-off. To their advantage flag-fields are very > efficient and simple to to parse. They are very compact, order of > fields in the packet is fixed, each field type occurs at most once in > the packet, and random access of specific fields is possible. I don't > foresee the need to add a whole bunch of new fields, and those add > will likely be generic supporting "pluggable" semantics (like the > security field in the draft). Other similar generic fields we've > contemplated are a long inner flow identifier, QoS/classification, and > congestion control. > 7) We have deployed a variant of this protocol at scale and it is > working pretty well! > 8) I have posted patches for the initial GUE draft on Linux netdev. > These implement IPIP/GUE, SIT/GUE, and GRE/GUE (also implements > GRE/UDP draft). In testing we did demonstrate the value of UDP > encapsulation to improve load balancing and steering in the network. > > Thanks, > Tom > > ---------- Forwarded message ---------- > From: <[email protected]> > Date: Tue, Mar 4, 2014 at 11:02 AM > Subject: New Version Notification for draft-herbert-gue-01.txt > To: Tom Herbert <[email protected]> > > > > A new version of I-D, draft-herbert-gue-01.txt > has been successfully submitted by Tom Herbert and posted to the > IETF repository. > > Name: draft-herbert-gue > Revision: 01 > Title: Generic UDP Encapsulation > Document date: 2014-03-05 > Group: Individual Submission > Pages: 20 > URL: http://www.ietf.org/internet-drafts/draft-herbert-gue-01.txt > Status: https://datatracker.ietf.org/doc/draft-herbert-gue/ > Htmlized: http://tools.ietf.org/html/draft-herbert-gue-01 > Diff: http://www.ietf.org/rfcdiff?url2=draft-herbert-gue-01 > > Abstract: > This specification describes Generic UDP Encapsulation (GUE), which > is a scheme for using UDP to encapsulate packets of arbitrary IP > protocols for transport across layer 3 networks. By encapsulating > packets in UDP, specialized capabilities in networking hardware for > efficient handling of UDP packets can be leveraged. GUE specifies > basic encapsulation methods upon which higher level constructs, such > tunnels and overlay networks, can be constructed. > > > > > 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. > > The IETF Secretariat > > _______________________________________________ > nvo3 mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/nvo3 _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
