diff --git a/advanced.rst b/advanced.rst
index 0fe7806..6ade5b3 100644
--- a/advanced.rst
+++ b/advanced.rst
@@ -11,6 +11,7 @@
    :glob:
 
    advanced/connectivity
-   advanced/upf
+   advanced/p4-upf
+   advanced/bess-upf
    advanced/int
    advanced/qos
diff --git a/advanced/bess-upf.rst b/advanced/bess-upf.rst
new file mode 100644
index 0000000..d79430f
--- /dev/null
+++ b/advanced/bess-upf.rst
@@ -0,0 +1,13 @@
+.. SPDX-FileCopyrightText: 2021 Open Networking Foundation <info@opennetworking.org>
+.. SPDX-License-Identifier: Apache-2.0
+
+BESS-based User Plane Function (BESS-UPF)
+=========================================
+
+.. note::
+
+    We are transitioning BESS-UPF from SD-Core to SD-Fabric.
+    We are also working on consolidating interfaces required by BESS-UPF to simplify deployment.
+    More documentation and architectural contents are coming shortly once these are done.
+    For now, please refer to :ref:`BESS UPF Deployment <aether:edge_deployment/bess_upf_deployment:bess upf deployment>`
+    to learn more about how to configure and deploy BESS-UPF.
diff --git a/advanced/upf.rst b/advanced/p4-upf.rst
similarity index 100%
rename from advanced/upf.rst
rename to advanced/p4-upf.rst
diff --git a/architecture.rst b/architecture.rst
index f44a264..c62f132 100644
--- a/architecture.rst
+++ b/architecture.rst
@@ -121,7 +121,9 @@
 applications that is multi-terabit and low-latency, without taking away CPU processing power for
 containers or VMs. In contrast to UPF solutions based on full or partial smartNIC offload,
 SD-Fabric's embedded UPF does not require additional hardware other than the same leaf and spine
-switches used to interconnect servers and base stations. At the same time, SD-Fabric can be
+switches used to interconnect servers and base stations.
+
+At the same time, SD-Fabric can be
 integrated with both CPU-based or smartNIC-based UPFs to improve scale while supporting
 differentiated services on a hardware-based fast-path at line rate for mission critical 4G/5G
 applications (see https://opennetworking.org/sd-core/ for more details).
diff --git a/specification.rst b/specification.rst
index 43e66fc..c8fa016 100644
--- a/specification.rst
+++ b/specification.rst
@@ -82,12 +82,33 @@
 Data Plane Programmability
 --------------------------
 - Support for Stratum, P4Runtime/gNMI, and P4 programs
-- Innovative services enabled by programmable data plane:
+- Open source fabric-tna P4 program that can be modified for additional features
 
-  - 4G/5G User Plane Function (UPF): GTP encap/decap, usage reporting, downlink buffering and data notifications,
-    QoS and more, with integration with mobile core control plane via PFCP protocol (3GPP standard interface).
-  - Inband Network Telemetry (INT): INT-XD mode with support for flow reports, drop reports,
-    queue congestion reports, with smart filters to reduce volume of reports ingested by the INT collector.
+4G & 5G
+-------
+- Two User Plane Function (UPF) implementations:
+
+  - Switch-based with fast path realized on Tofino with P4 (P4-UPF)
+  - CPU-based with fast path realized with Berkeley Extensible Software Switch framework (BESS-UPF)
+
+- Integration with mobile core control plane via PFCP protocol (3GPP standard interface)
+
+- Supported features:
+
+  - GTP encap/decap, including support for 5G QFI extension header
+  - Usage reporting rules (URR)
+  - Downlink buffering and data notifications
+  - Application filtering (via SDF filters)
+  - Per-application, per-session, per-slice rate limiting (via QER)
+  - Per-flow QoS metric (BESS-UPF only)
+
+Visibility
+----------
+  - Inband Network Telemetry (INT):
+
+    - INT-XD mode with support for flow reports, drop reports,
+      queue congestion reports
+    - Smart triggers/filters to reduce volume of reports ingested by the INT collector
 
 Troubleshooting & Diagnostics
 -----------------------------