RFC 1275

RFC 1275: Replication Requirements to provide an Internet Directory using X.500 💖

okay bestie, let's start with the header facts 🎀

• Network Working Group 🌸
• Author: S.E. Hardcastle-Kille, University College London 🎓
• Date: November 1991 📅
• Category/status: provides information for the Internet community. It does not specify an Internet standard. 💅
• Obsoletes: none listed in the header 🙅
• Updates: none listed in the header 🙅

Status of this Memo ✨

so this memo is here to give info to the Internet community 🫶 it is not an Internet standard, it just doesn't specify one. distribution of this memo is unlimited, so share it with everyone 🦋

Abstract 🔥

okay so this RFC looks at some deficiencies of the 1988 X.500 standard 👀 these need fixing before we can set up an effective open Internet Directory using these protocols and services [CCI88]. the only areas we're covering are the primary problems, the ones that must be solved before a pilot can be deployed. and this RFC focuses only on the stuff that can be fixed with extra protocol or procedures for distributed operation. main character energy, honestly 👑

1. Distributed Operation Extensions 🦋

the Internet Directory is going to run DSAs over TCP/IP using RFC 1006 [RC87], and also DSAs over an ISO Network Service. ✨ and distributed operation procedures should not require full connectivity, because that would be a whole mess 🙈

2. Knowledge Replication 🌈

knowledge info is critical for resolving names and doing searches 💖 the knowledge info high up the tree needs to be widely available. like, picture resolving a name below Country=US. to do that, a DSA needs full knowledge at that point. so many DSAs need to be able to do this in order to respond reasonably and stay available 😭 forcing all of that resolution onto one DSA, or a small number of them, would be an unacceptable bottleneck. so to spread this knowledge widely, we need a systematic approach to replication 🧚

3. Data Replication 🍓

searches usually happen at the root and country level, and that's a vital service (think an approximate match of an organisation name) 💅 so the data has to be collected in a way that makes this kind of searching reasonably efficient. the usual X.500 approach of subordinate references works against that. at a node in the DIT, subordinate references to the entries below are held. those entries can live in many DSAs, and each one has to be accessed to do the single level search 💀 so it's suggested that replicating the data is necessary to get this working.

the major requirement for this replication is high up the DIT, where information must be replicated between different implementations 🔥 lower down the DIT, it's reasonable for DSAs to be the same implementation and to use implementation specific techniques for performance and availability. ✨

4. Alternate DSAs 💜

when a DSA Referral comes back, only the master DSA is indicated 😬 that leads to a single point of failure, which is not it. it's important to allow for extra references to slave copies so we can get better availability 🫶 this has to be solved together with the problem from the previous section.

5. Guidelines for use of Replication 🌸

to be effective, the replication specification needs to give guidelines for deployment in the pilot, so it can hit the service criteria we want. 💅

6. Some scaling targets ⭐

most replication techniques have scaling limits, so the mechanisms we use shouldn't stress those limits 🙈 the order of magnitude envisioned for the pilot is 100 000 non-leaf entries and several million leaf entries. big numbers, bestie 😭

References 📚

• [CCI88] The Directory --- overview of concepts, models and services, December 1988. CCITT X.500 Series Recommendations.
• [RC87] Marshall T. Rose and Dwight E. Cass. ISO Transport Services on top of the TCP. Request for Comments 1006, Northrop Corporation Technology Center, May 1987.

7. Security Considerations 💀

security considerations are not discussed in this memo. 💀 that's the whole entry, no cap, so keep this in mind when reading it 👀

8. Author's Address 🧚

Steve Hardcastle-Kille
Department of Computer Science
University College London
Gower Street
WC1E 6BT
England

Phone:  +44-71-380-7294

EMail:  S.Kille@CS.UCL.AC.UK

and that's the whole RFC, bestie 💖🦋✨