diff --git a/server/XfrmController.cpp b/server/XfrmController.cpp
index cc2c305..d31b243 100644
--- a/server/XfrmController.cpp
+++ b/server/XfrmController.cpp
@@ -78,7 +78,7 @@
 
 namespace {
 
-constexpr uint32_t RAND_SPI_MIN = 1;
+constexpr uint32_t RAND_SPI_MIN = 256;
 constexpr uint32_t RAND_SPI_MAX = 0xFFFFFFFE;
 
 constexpr uint32_t INVALID_SPI = 0;