Subject: [Srcomp] section 3.1 closures

From: "Darren Dukes (ddukes)" <[email-masked]>
Date: Mon, 12 Oct 2020 12:40:49 +0000

Ron and I met several times last week, and we have pretty good agreement on the 3.1 text as follows, we can close over email:

3.1.1 text remains as is, we record both E and ES.
3.1.4 PROPORTIONALITY requirement is removed.

3.1.2.  REQ-8-17-FWD-EFFICIENCY

   o  Description:The compression solution SHOULD minimize the number of
      required hardware resources accessed to process a segment.

   o  Rational:Efficiency in bits on the wire and processing efficiency
      are both important.  Optimizing one at the expense of the other
      may lead to issues in implementations.

   o  Metric:The data plane efficiency metric (D) records the data plane
      forwarding efficiency of the proposed solution.  Two
      metrics are used and recorded at the segment endpoint and ultimate
      segment endpoint:

      *  D.PRS(segment list): number of headers parsed during
         processing of the segment list.

      *  D.LKU(segment list): number of FIB lookups during
         processing of the segment list. The type of lookup is also recorded as longest prefix match (LPM) or index match (IM).

3.1.3.  REQ-8-17-STATE-EFFICIENCY

   o  Description:The compression solution SHOULD minimize the amount of additional forwarding state stored at a node.

   o  Rational:Additional state will increase the complexity of the control
      plane and data plane. It can also result in an increase in memory usage.

   o  Metric:The state efficiency metric (S) records amount of additional forwarding state required by the proposed solution.

      *  S(node parameters): the number of additional forwarding states that need to be stored at a
         node, given a set of node parameters consisting of number of
         nodes in the network, number of local interface, number of
         adjacencies.  The forwarding state is counted as entries required in a Fowarding Information Base (FIB) at a node.  An implementation may choose to store FIB entries in a way that is not a 1:1 translation of the state recorded by this metric.

Darren