- TCP header adds 20 bytes
- IPv4 header adds 20 bytes
- IPv6 header adds 40 bytes
- GRE (IP Protocol 47) (RFC 2784) adds 24 bytes (20 byte IPv4 header, 4 byte GRE header)
- 6in4 encapsulation (IP Protocol 41, RFC 4213) adds 20 bytes
- 4in6 encapsulation (e.g. DS-Lite RFC 6333) adds 40 bytes
- Any time you add another outer IPv4 header adds 20 bytes
- IPsec encryption performed by the DMVPN adds 73 bytes for ESP-AES-256 and ESP-SHA-HMAC overhead (overhead depends on transport or tunnel mode and the encryption/authentication algorithm and HMAC)
- MPLS adds 4 bytes for each label in the stack
- IEEE 802.1Q tag adds 4 bytes (Q-in-Q would add 8 bytes)
- VXLAN adds 50 bytes
- OTV adds 42 bytes
- LISP adds 36 bytes for IPv4 and 56 bytes for IPv6 encapsulation
- NVGRE adds 42 bytes
- STT adds 54 bytes