TCP Packets Retransmission Size Larger than 1460
Filter: (tcp.analysis.retransmission || tcp.analysis.out_of_order) and tcp.len > 1460
Statistic of retransmitted packets which tcp.len > 1460.
For Ethernet, the standard MTU is 1500 bytes (this is the payload size inside the Ethernet frame, not including headers).
Packet Size with MTU 1500
Ethernet Header: 14 bytes
IP Header: 20 bytes (IPv4, without options)
TCP Header: 20 bytes (without options)
Data (payload): Up to 1460 bytes (1500 − 20 − 20)
Common MTU Sizes |
||
Technology / Protocol |
Typical MTU (bytes) |
Notes |
Ethernet (standard) |
1500 |
Most common MTU on LANs. |
Ethernet (with VLAN tag, 802.1Q) |
1500 (payload) / 1522 (frame size) |
VLAN tag adds 4 bytes but doesn’t change MTU. |
Jumbo Frames |
9000 (sometimes 9216) |
Used in data centers, storage (iSCSI, NFS). Must be supported end-to-end. |
PPPoE |
1492 |
8-byte PPPoE header reduces MTU. |
GRE Tunnel |
~1476 |
GRE adds 24 bytes overhead. |
IPSec VPN (ESP in tunnel mode) |
~1400–1430 |
Depends on encryption/auth overhead. |
DSL (PPPoE/ATM) |
1492 or lower (e.g., 1454) |
Encapsulation overhead reduces MTU. |
Wi-Fi (802.11) |
1500 |
Same as Ethernet by default. |
Loopback (localhost) |
65535 |
Typically max possible size. |
IPv6 minimum link MTU |
1280 |
Required by standard, though most use 1500. |
Please compare "TCP Packets Retransmission" and "TCP Packets Retransmission Size Larger than 1460" report.
Please verify path MTU between two endpoints if most of transmitted packets are with size larger than 1460.
How to verify path MTU:
Linux / macOS
Use ping with DF flag (-M do) and gradually increase size:
ping -M do -s 1472 <destination>
-M do → don’t fragment