drop a typo
diff --git a/rfc/sp-zerotier-mapping-01.xml b/rfc/sp-zerotier-mapping-01.xml
index 89b9917..4ff8c9a 100644
--- a/rfc/sp-zerotier-mapping-01.xml
+++ b/rfc/sp-zerotier-mapping-01.xml
@@ -35,7 +35,7 @@
<section title="Underlying protocol">
<t>ZeroTier expresses an 802.3 style layer 2, where frames
- maybe excchanged as if they were Ethernet frames. Virtual broadcast
+ maybe exchanged as if they were Ethernet frames. Virtual broadcast
domains are created within a numbered "network", and frames may then
be exchanged with any peers on that network.</t>
