1<?xml version="1.0"?> 2<element xmlns="http://relaxng.org/ns/structure/1.0" name="device"> 3 <choice> 4 <group> 5 <attribute name="link"> 6 <value>ethernet</value> 7 </attribute> 8 <optional> 9 <element name="ethernet-element"> 10 <text/> 11 </element> 12 </optional> 13 </group> 14 <group> 15 <attribute name="link"> 16 <value>serial</value> 17 </attribute> 18 <optional> 19 <element name="serial-element"> 20 <text/> 21 </element> 22 </optional> 23 </group> 24 </choice> 25</element> 26