updated SONiC section

Author: llpeterson

README.rst

@@ -6,7 +6,7 @@ source for *Software-Defined Networks: A Systems Approach*, available under
 terms of the `Creative Commons (CC BY-NC-ND 4.0)
 <https://creativecommons.org/licenses/by-nc-nd/4.0>`__ license. The
 community is invited to contribute corrections, improvements, updates,
-and new material under the same terms. While this licence does not
+and new material under the same terms. While this license does not
 automatically grant the right to make derivative works, we are keen to
 discuss derivative works (such as translations) with interested
 parties. Please reach out to

access.rst

@@ -43,8 +43,8 @@ edge of the ISP’s network—the ISP-side of the last-mile that directly
 connects to customers. The PON and RAN-based access networks are
 anchored in these facilities.
 
-Passive Optical Network 
-~~~~~~~~~~~~~~~~~~~~~~~
+9.1.1 Passive Optical Network 
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 A PON is a tree-structured, fiber-based network, starting with a
 single device in one of the ISP's edge sites, and fanning out to reach
@@ -91,8 +91,8 @@ higher bandwidths. G-PON (Gigabit-PON) is the most widely deployed
 today, supporting a bandwidth of 2.25-Gbps. XGS-PON (10 Gigabit-PON)
 is now being deployed.
 
-Radio Access Network
-~~~~~~~~~~~~~~~~~~~~
+9.1.2 Radio Access Network
+~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 A RAN implements the last hop by encoding and transmitting data at
 various bandwidths in the radio spectrum.  For example, traditional
@@ -143,8 +143,8 @@ to jointly transmit to a given UE).
        implement a distributed decision-making algorithm, and then
        forward packets to each other based on those decisions.
 
-Key Takeaways
-~~~~~~~~~~~~~~~~
+9.1.3 Key Takeaways
+~~~~~~~~~~~~~~~~~~~
 
 There are three observations to make about these two network
 technologies before we get to the question of how to apply SDN
@@ -329,8 +329,8 @@ has a local packet scheduler), but they do exert near real-time
 control over the base stations, with control loops measured in less
 than ten milliseconds.
 
-Split RAN
-~~~~~~~~~
+9.3.1 Split RAN
+~~~~~~~~~~~~~~~
 
 To better see how this works, we start with a finer-grain view of the
 packet processing pipeline running on each base station shown in
@@ -421,8 +421,8 @@ geographic area (e.g., a mall, campus, or factory), then a single DU
 would likely service multiple RUs. The use of mmWave in 5G is likely
 to make this later configuration all the more common.
 
-RAN Intelligent Controller
-~~~~~~~~~~~~~~~~~~~~~~~~~~
+9.3.2 RAN Intelligent Controller
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 The RRU, shown in :numref:`Figure %s <fig-basestation>` as part of
 each basestation and shown in :numref:`Figure %s <fig-split-ran>` as
@@ -512,8 +512,8 @@ collect the available input data centrally, make a globally optimal
 decision, and then push the respective control parameters back to the
 base stations for execution.
 
-RIC Interfaces
-~~~~~~~~~~~~~~~~~~~
+9.3.3 RIC Interfaces
+~~~~~~~~~~~~~~~~~~~~
 
 Returning to the three interfaces called out in :numref:`Figure %s
 <fig-ric>`, each serves a purpose similar to the interfaces described

stratum.rst

@@ -402,21 +402,27 @@ As a reminder, if you are unfamiliar with protobufs, a brief overview is availab
 
 In the same way SAI is an industry-wide switch abstraction (see
 Section 4.5), SONiC is a vendor-agnostic Switch OS that is gaining a
-lot of momentum in the industry. SONiC, which leverages SAI as a
-vendor-agnostic SDK and was originally open sourced by Microsoft,
-continues to serve as the Switch OS for the Azure Cloud. And like
-Stratum, SONiC can also leverage Open Networking Linux (ONL) as its
-underlying operating system. All of which is to say that Stratum and
-SONiC both try to fill the same need. Today their respective
-approaches are largely complementary, with both open source
-communities working towards a “best of both worlds” solution.
+lot of momentum in the industry. It was originally open sourced by
+Microsoft and continues to serve as the Switch OS for the Azure Cloud.
+SONiC leverages SAI as a vendor-agnostic SDK and includes a
+switch-customized Linux distribution, which is to say, Stratum and
+SONiC try to fill the same need. Today their respective approaches are
+largely complementary, with the two open source communities working
+towards a “best of both worlds” solution. This effort is known as *PINS*,
+which stands for *P4 Integrated Network Stack.*
+
+.. _reading_pins:
+.. admonition:: Further Reading
+
+   `PINS: P4 Integrated Network Stack
+   <https://opennetworking.org/pins/>`__.
 
 Both SONiC and Stratum support a configuration interface, so unifying
 those will be a matter of reconciling their respective data models and
 toolchains. The main distinction is Stratum’s support for programmable
 forwarding pipelines (including both P4 and P4Runtime), versus the
-least common denominator approach to forwarding taken by
-SAI. Developers on the two open source projects are working together
+least common denominator approach to forwarding taken by SAI.
+Developers on the two open source projects are working together
 to define a roadmap that will make it possible for interested networks
 to take advantage of programmable pipelines in an incremental and
 low-risk way.