+ The port argument is the TX port like in the "csum set" command.
+
+Example:
+
+Consider a packet as following:
+"eth_out/ipv4_out/udp_out/vxlan/eth_in/ipv4_in/tcp_in"
+
+- If parse-tunnel is enabled, the ip|udp|tcp|sctp parameters of "csum
+ set" command are about inner headers (here ipv4_in and tcp_in), and the
+ outer-ip parameter is about outer headers (here ipv4_out).
+
+- If parse-tunnel is disabled, the ip|udp|tcp|sctp parameters of "csum
+ set" command are about outer headers, here ipv4_out and udp_out.
+
+csum show
+~~~~~~~~~
+
+Display tx checksum offload configuration:
+
+csum show (port_id)
+
+tso set
+~~~~~~~
+
+Enable TCP Segmentation Offload in csum forward engine:
+
+tso set (segsize) (port_id)
+
+.. note::
+
+ Check the NIC datasheet for hardware limits
+
+tso show
+~~~~~~~~