SQL> SELECT name, value
  2  FROM   v$sysstat
  3  WHERE  LOWER(name) LIKE '%net%'
  4  /

NAME                                                                  VALUE
---------------------------------------------------------------- ----------
bytes sent via SQL*Net to client                                      74270
bytes received via SQL*Net from client                                10002
SQL*Net roundtrips to/from client                                       105
bytes sent via SQL*Net to dblink                                          0
bytes received via SQL*Net from dblink                                    0
SQL*Net roundtrips to/from dblink                                         0

6 rows selected.