diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 87c8e8c..eaaeb0e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -12,16 +12,60 @@ on:
 jobs:
   test:
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - stable
+          - beta
+          - nightly
+        target:
+          - aarch64-unknown-linux-gnu
+          - aarch64-unknown-linux-musl
+          - riscv64gc-unknown-linux-gnu
+          - x86_64-unknown-linux-gnu
+          - x86_64-unknown-linux-musl
+    env:
+      CARGO_BUILD_TARGET: ${{ matrix.target }}
+      RUST_BACKTRACE: full
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
-      - uses: actions-rs/toolchain@v1
-        with:
-          toolchain: nightly
-          override: true
+      - name: Install cross-compilation tools
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y gcc-aarch64-linux-gnu gcc-riscv64-linux-gnu musl-tools
 
-      - name: Test
-        env:
-          RUST_BACKTRACE: full
+      - name: Configure Cargo for cross-compilation
         run: |
-          cargo test --verbose
+          mkdir -p .cargo
+          cat > .cargo/config.toml <<EOL
+          [target.aarch64-unknown-linux-gnu]
+          linker = "aarch64-linux-gnu-gcc"
+
+          [target.aarch64-unknown-linux-musl]
+          linker = "aarch64-linux-gnu-gcc"
+
+          [target.riscv64gc-unknown-linux-gnu]
+          linker = "riscv64-linux-gnu-gcc"
+          EOL
+
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ matrix.rust }}
+          components: rustfmt, clippy, rust-src
+          targets: ${{ matrix.target }}
+
+      - name: Check formatting
+        if: matrix.rust == 'stable'
+        run: cargo fmt --all -- --check
+
+      - name: Clippy
+        run: cargo clippy -- --deny warnings -A clippy::useless_transmute -A clippy::too_many_arguments
+
+      - name: Build tests for cross-targets
+        if: contains(matrix.target, 'aarch64') || contains(matrix.target, 'riscv64')
+        run: cargo build --tests --verbose
+
+      - name: Run tests on native target
+        if: contains(matrix.target, 'x86_64')
+        run: cargo test --verbose
diff --git a/README.md b/README.md
index 27adabc..70870d8 100644
--- a/README.md
+++ b/README.md
@@ -118,6 +118,4 @@ feature flag. It is intended to be used with binary serialization libraries
 like [`bincode`](https://crates.io/crates/bincode) that leverage Serde's
 infrastructure.
 
-Note that `no_std` support is lost when enabling Serde.
-
 License: MIT
diff --git a/src/geneve.rs b/src/geneve.rs
new file mode 100644
index 0000000..43c8ca1
--- /dev/null
+++ b/src/geneve.rs
@@ -0,0 +1,261 @@
+/// Represents a Geneve (Generic Network Virtualization Encapsulation) header, according to RFC 8926.
+/// Geneve is an encapsulation protocol designed for network virtualization.
+///
+#[repr(C, packed)]
+#[derive(Debug, Copy, Clone, Default)]
+
+pub struct GeneveHdr {
+    /// Combined field: Version (2 bits) and Option Length (6 bits).
+    pub ver_opt_len: u8,
+    /// Combined field: OAM flag (1 bit), Critical flag (1 bit), Reserved (6 bits).
+    pub o_c_rsvd: u8,
+    /// Protocol Type of the encapsulated payload (16 bits).
+    pub protocol_type: [u8; 2],
+    /// Virtual Network Identifier (VNI) (24 bits).
+    pub vni: [u8; 3],
+    /// Reserved field (8 bits). MUST be zero on transmission.
+    pub reserved2: u8,
+}
+
+impl GeneveHdr {
+    /// The length of the Geneve header in bytes.
+    pub const LEN: usize = core::mem::size_of::<GeneveHdr>();
+
+    /// Returns the Geneve protocol version (2 bits).
+    ///
+    /// According to RFC 8926, the current version is 0.
+    #[inline]
+    pub fn ver(&self) -> u8 {
+        (self.ver_opt_len >> 6) & 0x03
+    }
+
+    /// Sets the Geneve protocol version (2 bits).
+    ///
+    /// `ver` should be a 2-bit value (0-3).
+    #[inline]
+    pub fn set_ver(&mut self, ver: u8) {
+        let preserved_bits = self.ver_opt_len & 0x3F;
+        self.ver_opt_len = preserved_bits | ((ver & 0x03) << 6);
+    }
+
+    /// Returns the length of the option fields in 4-byte multiples (6 bits).
+    #[inline]
+    pub fn opt_len(&self) -> u8 {
+        self.ver_opt_len & 0x3F
+    }
+
+    /// Sets the length of the option fields (6 bits).
+    ///
+    /// `opt_len` should be a 6-bit value (0-63).
+    #[inline]
+    pub fn set_opt_len(&mut self, opt_len: u8) {
+        let preserved_bits = self.ver_opt_len & 0xC0;
+        self.ver_opt_len = preserved_bits | (opt_len & 0x3F);
+    }
+
+    /// Returns the OAM (Operations, Administration, and Maintenance) packet flag (1 bit).
+    ///
+    /// If set (1), this packet is an OAM packet. Referred to as 'O' bit in RFC 8926.
+    #[inline]
+    pub fn o_flag(&self) -> u8 {
+        (self.o_c_rsvd >> 7) & 0x01
+    }
+
+    /// Sets the OAM packet flag (1 bit).
+    ///
+    /// `o_flag` should be a 1-bit value (0 or 1).
+    #[inline]
+    pub fn set_o_flag(&mut self, o_flag: u8) {
+        let preserved_bits = self.o_c_rsvd & 0x7F;
+        self.o_c_rsvd = preserved_bits | ((o_flag & 0x01) << 7);
+    }
+
+    /// Returns the Critical Options Present flag (1 bit).
+    ///
+    /// If set (1), one or more options are marked as critical. Referred to as 'C' bit in RFC 8926.
+    #[inline]
+    pub fn c_flag(&self) -> u8 {
+        (self.o_c_rsvd >> 6) & 0x01
+    }
+
+    /// Sets the Critical Options Present flag (1 bit).
+    ///
+    /// `c_flag` should be a 1-bit value (0 or 1).
+    #[inline]
+    pub fn set_c_flag(&mut self, c_flag: u8) {
+        let preserved_bits = self.o_c_rsvd & 0xBF;
+        self.o_c_rsvd = preserved_bits | ((c_flag & 0x01) << 6);
+    }
+
+    /// Returns the Protocol Type of the encapsulated payload (16 bits, network byte order).
+    ///
+    /// This follows the Ethertype convention.
+    #[inline]
+    pub fn protocol_type(&self) -> u16 {
+        u16::from_be_bytes(self.protocol_type)
+    }
+
+    /// Sets the Protocol Type (16 bits).
+    ///
+    /// The value is stored in network byte order.
+    #[inline]
+    pub fn set_protocol_type(&mut self, protocol_type: u16) {
+        self.protocol_type = protocol_type.to_be_bytes();
+    }
+
+    /// Returns the Virtual Network Identifier (VNI) (24 bits).
+    #[inline]
+    pub fn vni(&self) -> u32 {
+        u32::from_be_bytes([0, self.vni[0], self.vni[1], self.vni[2]])
+    }
+
+    /// Sets the Virtual Network Identifier (VNI) (24 bits).
+    ///
+    /// `vni` should be a 24-bit value. Higher bits are masked.
+    /// The value is stored in network byte order.
+    #[inline]
+    pub fn set_vni(&mut self, vni: u32) {
+        let vni_val = vni & 0x00FFFFFF;
+        let bytes = vni_val.to_be_bytes();
+        self.vni[0] = bytes[1];
+        self.vni[1] = bytes[2];
+        self.vni[2] = bytes[3]
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_len() {
+        assert_eq!(GeneveHdr::LEN, 8);
+    }
+
+    #[test]
+    fn test_default() {
+        let hdr = GeneveHdr::default();
+        assert_eq!(hdr.ver_opt_len, 0);
+        assert_eq!(hdr.o_c_rsvd, 0);
+        assert_eq!(hdr.protocol_type, [0, 0]);
+        assert_eq!(hdr.vni, [0, 0, 0]);
+        assert_eq!(hdr.reserved2, 0);
+
+        assert_eq!(hdr.ver(), 0);
+        assert_eq!(hdr.opt_len(), 0);
+        assert_eq!(hdr.o_flag(), 0);
+        assert_eq!(hdr.c_flag(), 0);
+        assert_eq!(hdr.protocol_type(), 0);
+        assert_eq!(hdr.vni(), 0);
+    }
+
+    #[test]
+    fn test_ver() {
+        let mut hdr = GeneveHdr::default();
+        hdr.set_ver(0b10); // Version 2
+        assert_eq!(hdr.ver(), 0b10);
+        assert_eq!(hdr.ver_opt_len, 0b10000000, "Raw byte for ver failed");
+
+        hdr.set_ver(0b111); // Input 7 (3 bits), should be masked to 0b11 (3)
+        assert_eq!(hdr.ver(), 0b11);
+        assert_eq!(hdr.ver_opt_len, 0b11000000, "Masking for ver failed");
+
+        // Test interaction with opt_len
+        hdr.ver_opt_len = 0; // Reset
+        hdr.set_opt_len(0x3F); // Max opt_len (all lower 6 bits set)
+        hdr.set_ver(0b01);
+        assert_eq!(hdr.ver(), 0b01);
+        assert_eq!(hdr.opt_len(), 0x3F, "opt_len altered by set_ver");
+        assert_eq!(hdr.ver_opt_len, 0b01111111, "Interaction with opt_len failed");
+    }
+
+    #[test]
+    fn test_opt_len() {
+        let mut hdr = GeneveHdr::default();
+        hdr.set_opt_len(0x2A); // 42
+        assert_eq!(hdr.opt_len(), 0x2A);
+        assert_eq!(hdr.ver_opt_len, 0b00101010, "Raw byte for opt_len failed");
+
+        hdr.set_opt_len(0xFF); // Input 255, should be masked to 0x3F (63)
+        assert_eq!(hdr.opt_len(), 0x3F);
+        assert_eq!(hdr.ver_opt_len, 0b00111111, "Masking for opt_len failed");
+
+        // Test interaction with ver
+        hdr.ver_opt_len = 0; // Reset
+        hdr.set_ver(0b11); // Max ver (top 2 bits set)
+        hdr.set_opt_len(0x15); // 21
+        assert_eq!(hdr.ver(), 0b11, "ver altered by set_opt_len");
+        assert_eq!(hdr.opt_len(), 0x15);
+        assert_eq!(hdr.ver_opt_len, 0b11010101, "Interaction with ver failed");
+    }
+
+    #[test]
+    fn test_o_flag() {
+        let mut hdr = GeneveHdr::default();
+        hdr.set_o_flag(1);
+        assert_eq!(hdr.o_flag(), 1);
+        assert_eq!(hdr.o_c_rsvd, 0b10000000, "Raw byte for o_flag failed");
+
+        // The implementation correctly masks the input, so an input of 2 (0b10) becomes 0.
+        // This sets the o_flag back to 0.
+        hdr.set_o_flag(0b10);
+        assert_eq!(hdr.o_flag(), 0);
+        assert_eq!(hdr.o_c_rsvd, 0b00000000, "Masking for o_flag failed");
+
+        // Test that setting the O flag preserves the C flag and reserved bits.
+        hdr.o_c_rsvd = 0; // Reset
+        hdr.set_c_flag(1); // o_c_rsvd is now 0b01000000
+
+        // Now, set the O flag.
+        hdr.set_o_flag(1);
+
+        // Verify that only the O flag bit changed.
+        assert_eq!(hdr.o_flag(), 1, "o_flag should be 1");
+        assert_eq!(hdr.c_flag(), 1, "c_flag should be preserved");
+    }
+
+    #[test]
+    fn test_c_flag() {
+        let mut hdr = GeneveHdr::default();
+        hdr.set_c_flag(1);
+        assert_eq!(hdr.c_flag(), 1);
+        assert_eq!(hdr.o_c_rsvd, 0b01000000, "Raw byte for c_flag failed");
+
+        // The implementation correctly masks the input, so an input of 2 (0b10) becomes 0.
+        // This sets the c_flag back to 0.
+        hdr.set_c_flag(0b10);
+        assert_eq!(hdr.c_flag(), 0);
+        assert_eq!(hdr.o_c_rsvd, 0b00000000, "Masking for c_flag failed");
+
+        // Test that setting the C flag preserves the O flag and reserved bits.
+        hdr.o_c_rsvd = 0; // Reset
+        hdr.set_o_flag(1); // o_c_rsvd is now 0b10000000
+
+        // Now, set the C flag.
+        hdr.set_c_flag(1);
+
+        // Verify that only the C flag bit changed.
+        assert_eq!(hdr.c_flag(), 1, "c_flag should be 1");
+        assert_eq!(hdr.o_flag(), 1, "o_flag should be preserved");
+    }
+
+    #[test]
+    fn test_protocol_type() {
+        let mut hdr = GeneveHdr::default();
+        hdr.set_protocol_type(0xABCD);
+        assert_eq!(hdr.protocol_type(), 0xABCD);
+        assert_eq!(hdr.protocol_type, [0xAB, 0xCD], "Raw bytes for protocol_type failed (Big Endian check)");
+    }
+
+    #[test]
+    fn test_vni() {
+        let mut hdr = GeneveHdr::default();
+        hdr.set_vni(0x00123456);
+        assert_eq!(hdr.vni(), 0x00123456);
+        assert_eq!(hdr.vni, [0x12, 0x34, 0x56], "Raw bytes for VNI failed (Big Endian check)");
+
+        hdr.set_vni(0xFF123456); // Input with >24 bits
+        assert_eq!(hdr.vni(), 0x00123456, "Masking for VNI failed");
+        assert_eq!(hdr.vni, [0x12, 0x34, 0x56], "Raw bytes after VNI masking failed");
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index b5df8b5..d9373eb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,5 @@
 #![doc = include_str!("../README.md")]
-#![cfg_attr(not(feature = "std"), no_std)]
+#![no_std]
 
 pub mod arp;
 pub mod bitfield;
@@ -14,3 +14,4 @@ pub mod udp;
 pub mod vlan;
 pub mod vxlan;
 pub mod llc;
+pub mod geneve;
diff --git a/src/vxlan.rs b/src/vxlan.rs
index 1b3fc27..8caaa71 100644
--- a/src/vxlan.rs
+++ b/src/vxlan.rs
@@ -1,33 +1,245 @@
 use core::mem;
 
-use crate::bitfield::BitfieldUnit;
-
-/// VXLAN header, which is present at the beginning of every UDP payload containing VXLAN packets.
+/// VXLAN (Virtual eXtensible Local Area Network) header.
+///
+/// Encapsulates OSI layer 2 Ethernet frames within layer 4 UDP packets.
+/// Uses a 24-bit VXLAN Network Identifier (VNI) for traffic segregation.
+/// Header length: 8 bytes.
+/// Reference: RFC 7348.
 #[repr(C, packed)]
 #[derive(Debug, Copy, Clone)]
 #[cfg_attr(feature = "serde", derive(::serde::Serialize, ::serde::Deserialize))]
 pub struct VxlanHdr {
-    /// VXLAN flags. See [`VxlanHdr::vni_valid`] and [`VxlanHdr::set_vni_valid`].
-    pub flags: BitfieldUnit<[u8; 1usize]>,
-    pub _reserved: [u8; 3],
-    /// VXLAN Virtual Network Identifier.
-    ///
-    /// This is a 24-bit number combined with reserved bytes, see [`VxlanHdr::vni`] and
-    /// [`VxlanHdr::set_vni`].
+    /// Flags (8 bits). Bit 3 (I flag) must be 1 if VNI is present. Other bits are reserved (R).
+    pub flags: u8,
+    /// Reserved field (24 bits). Must be zero on transmission.
+    pub _reserved1: [u8; 3],
+    /// Contains the 24-bit VNI (upper 3 bytes) and an 8-bit reserved field (the lowest byte).
+    /// The reserved field (the lowest byte) must be zero on transmission.
     pub vni: [u8; 3],
-    pub _padding: u8,
+    pub _reserved2: u8,
 }
 
+/// Mask for the I-flag (VNI Present flag, bit 3) in the `flags` field.
+pub const VXLAN_I_FLAG_MASK: u8 = 0x08;
+
 impl VxlanHdr {
-    pub const LEN: usize = mem::size_of::<Self>();
+    /// Length of the VXLAN header in bytes (8 bytes).
+    pub const LEN: usize = mem::size_of::<VxlanHdr>();
+
+    /// Creates a new `VxlanHdr`.
+    ///
+    /// Sets the I-flag, zeros reserved fields, and sets the VNI.
+    ///
+    /// # Parameters
+    /// - `vni`: The 24-bit VXLAN Network Identifier.
+    ///
+    /// # Returns
+    /// A new `VxlanHdr` instance.
+    pub fn new(vni: u32) -> Self {
+        let mut hdr = VxlanHdr {
+            flags: VXLAN_I_FLAG_MASK,
+            _reserved1: [0u8; 3],
+            vni: [0u8; 3],
+            _reserved2: 0u8,
+        };
+        hdr.set_vni(vni);
+        hdr
+    }
+
+    /// Creates a new `VxlanHdr`.
+    ///
+    /// Sets the I-flag, zeros reserved fields, and sets the VNI.
+    ///
+    /// # Parameters
+    /// - `flags`: The 8-bit value to set for the flag field.
+    /// - `vni`: The 24-bit VXLAN Network Identifier.
+    ///
+    /// # Returns
+    /// A new `VxlanHdr` instance.
+    pub fn with_flags(flags: u8, vni: [u8; 3]) -> Self {
+        Self {
+            flags,
+            _reserved1: [0; 3],
+            vni,
+            _reserved2: 0,
+        }
+    }
+
+    /// Returns the raw flags' byte.
+    ///
+    /// # Returns
+    /// The 8-bit flags field.
+    #[inline]
+    pub fn flags(&self) -> u8 {
+        self.flags
+    }
+
+    /// Sets the raw flags byte.
+    ///
+    /// # Parameters
+    /// - `flags`: The 8-bit value to set for the flags field.
+    #[inline]
+    pub fn set_flags(&mut self, flags: u8) {
+        self.flags = flags;
+    }
+
+    /// Checks if the I-flag (VNI Present) is set.
+    ///
+    /// # Returns
+    /// `true` if the I-flag is set, `false` otherwise.
+    #[inline]
+    pub fn vni_present(&self) -> bool {
+        (self.flags & VXLAN_I_FLAG_MASK) == VXLAN_I_FLAG_MASK
+    }
 
+    /// Sets or clears the I-flag (VNI Present).
+    ///
+    /// Preserves other flag bits.
+    ///
+    /// # Parameters
+    /// - `present`: If `true`, sets the I-flag; otherwise, clears it.
     #[inline]
-    pub fn vni_valid(&self) -> bool {
-        self.flags.get_bit(4)
+    pub fn set_vni_present(&mut self, present: bool) {
+        if present {
+            self.flags |= VXLAN_I_FLAG_MASK;
+        } else {
+            self.flags &= !VXLAN_I_FLAG_MASK;
+        }
     }
 
+    /// Returns the VXLAN Network Identifier (VNI).
+    ///
+    /// # Returns
+    /// The 24-bit VNI as a `u32`.
+    #[inline]
+    pub fn vni(&self) -> u32 {
+        u32::from_be_bytes([0, self.vni[0], self.vni[1], self.vni[2]])
+    }
+
+    /// Sets the VXLAN Network Identifier (VNI).
+    ///
+    /// Masks the input `vni` to 24 bits. Preserves the `reserved2` field.
+    ///
+    /// # Parameters
+    /// - `vni`: The 24-bit VNI value.
     #[inline]
-    pub fn set_vni_valid(&mut self, val: bool) {
-        self.flags.set_bit(4, val)
+    pub fn set_vni(&mut self, vni: u32) {
+        let vni_24bit = vni & 0x00FF_FFFF;
+        let vni_bytes = vni_24bit.to_be_bytes();
+        self.vni[0] = vni_bytes[1];
+        self.vni[1] = vni_bytes[2];
+        self.vni[2] = vni_bytes[3];
+    }
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_vxlanhdr_len() {
+        assert_eq!(VxlanHdr::LEN, 8, "VXLAN header length should be 8 bytes");
+    }
+
+    #[test]
+    fn test_vxlanhdr_new() {
+        let vni_val: u32 = 0xABCDEF;
+        let hdr = VxlanHdr::new(vni_val);
+        assert_eq!(
+            hdr.flags(),
+            VXLAN_I_FLAG_MASK,
+            "Flags should have I-flag set and others zero"
+        );
+        assert!(hdr.vni_present(), "VNI present flag should be set by new()");
+        assert_eq!(hdr.vni(), vni_val, "VNI should be set correctly by new()");
+    }
+
+    #[test]
+    fn test_flags_management() {
+        let mut hdr = VxlanHdr::new(0x123);
+        hdr.set_flags(0xFF);
+        assert_eq!(hdr.flags(), 0xFF);
+        assert!(
+            hdr.vni_present(),
+            "I-flag should be set if flags byte is 0xFF"
+        );
+        hdr.set_flags(0x00);
+        assert!(
+            !hdr.vni_present(),
+            "I-flag should be clear if flags byte is 0x00"
+        );
+        hdr.set_vni_present(true);
+        assert_eq!(
+            hdr.flags(),
+            VXLAN_I_FLAG_MASK,
+            "set_vni_present(true) should set I-flag"
+        );
+        assert!(hdr.vni_present());
+        hdr.set_vni_present(false);
+        assert_eq!(
+            hdr.flags(),
+            0x00,
+            "set_vni_present(false) should clear I-flag"
+        );
+        assert!(!hdr.vni_present());
+        hdr.set_flags(0xF0);
+        assert!(!hdr.vni_present());
+        hdr.set_vni_present(true);
+        assert_eq!(
+            hdr.flags(),
+            0xF0 | VXLAN_I_FLAG_MASK,
+            "Setting I-flag should preserve other bits"
+        );
+        assert!(hdr.vni_present());
+        hdr.set_vni_present(false);
+        assert_eq!(
+            hdr.flags(),
+            0xF0 & !VXLAN_I_FLAG_MASK,
+            "Clearing I-flag should preserve other bits"
+        );
+        assert!(!hdr.vni_present());
+    }
+
+    #[test]
+    fn test_vni_management() {
+        let mut hdr = VxlanHdr::new(0);
+        let vni_val: u32 = 0xABCDEF;
+        hdr.set_vni(vni_val);
+        assert_eq!(hdr.vni(), vni_val, "VNI should be set correctly");
+        let large_vni: u32 = 0x12ABCDEF;
+        hdr.set_vni(large_vni);
+        assert_eq!(hdr.vni(), 0xABCDEF, "VNI should be masked to 24 bits");
+        hdr.set_vni(0);
+        assert_eq!(hdr.vni(), 0, "VNI should be settable to 0");
+        let max_vni: u32 = 0xFFFFFF;
+        hdr.set_vni(max_vni);
+        assert_eq!(hdr.vni(), max_vni, "Max 24-bit VNI should be settable");
+        hdr.set_vni(0x123456);
+        assert_eq!(hdr.vni(), 0x123456, "VNI should be updated");
+    }
+
+    #[test]
+    fn test_field_storage_and_retrieval_direct_manipulation() {
+        let mut hdr = VxlanHdr::with_flags(0x08, [0xAB, 0xCD, 0xEF]);
+        hdr.flags = 0x08;
+        hdr.vni = [0xAB, 0xCD, 0xEF];
+        assert_eq!(hdr.flags(), 0x08);
+        assert!(hdr.vni_present());
+        assert_eq!(hdr.vni(), 0xABCDEF);
+        hdr.set_vni_present(false);
+        assert_eq!(
+            hdr.flags, 0x00,
+            "Direct field check after set_vni_present(false)"
+        );
+        hdr.set_vni(0x654321);
+        assert_eq!(hdr.vni[0], 0x65, "Byte 0 of vni after set_vni");
+        assert_eq!(hdr.vni[1], 0x43, "Byte 1 of vni after set_vni");
+        assert_eq!(hdr.vni[2], 0x21, "Byte 2 of vni after set_vni");
+        assert_eq!(hdr.vni(), 0x654321);
+        assert_eq!(
+            hdr.vni[0], 0x65,
+            "Byte 0 of vni preserved after set_reserved2"
+        );
+        assert_eq!(hdr.vni(), 0x654321);
     }
 }