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Optimal MTU, MSS & Bufferbloat SQM Calculator

Calculate the perfect unfragmented MTU and MSS for PPPoE fiber or VPN tunnels and determine exact SQM (CAKE / FQ_CoDel) bandwidth limits to eliminate ping spikes.

Parameters & Controls

ISP Encapsulation & Protocol

Measured Download600 Mbps

Measured Upload600 Mbps

Average Round-Trip Ping (RTT ms)18 ms

Router Queue Algorithm (SQM / QoS)

Telemetry Console & Results

64-bit IEEE 754

Optimal Unfragmented MTU

1492Bytes

MSS: 1452 bytes | Ping payload: 1464

Line Traffic Shaping Ratio92%

Detailed Mathematical Breakdown

Maximum Segment Size (MSS IPv4)MTU minus 40 bytes IP/TCP header

1452bytes

Unfragmented Ping Test PayloadMTU minus 28 bytes IP/ICMP

1464bytes

SQM Download Rate LimitApply to router ingress queue

552 Mbps(552000 kbps)

SQM Upload Rate LimitPrevents ping spikes during upload

552 Mbps(552000 kbps)

Optimal BDP TCP Window SizeBandwidth-Delay Product capacity

1318KB

Applied Equation (Live Input):

MSS = MTU (1492) - 40 = 1452 bytes | Payload_Ping = MTU - 28 = 1464 bytes

Precalculated Engineering Configurations & Benchmarks

Direct access to high-intent hardware and game configurations with verified mathematical solutions:

Optimal MTU for PS5 on PPPoE Fiber Connections (1492)

Determine optimal MTU for PlayStation 5 on PPPoE fiber. Eliminate packet fragmentation and latency spikes in online matchmaking.

SQM (CAKE) Anti-Bufferbloat Tuning for PC Gaming

Calculate exact upload and download shaping caps to configure SQM CAKE in your router. Keep gaming ping flat at 15ms under full saturation.

Technical Methodology & Reference Guide

Bufferbloat occurs when network equipment buffers too many packets during heavy traffic, introducing massive latency spikes (jitter) in competitive games. Enabling Smart Queue Management (SQM) with the CAKE algorithm and pacing bandwidth to ~90% of your physical line forces buffers to empty immediately, maintaining near-zero ping fluctuation.

Windows CMD / PowerShell

ping -f -l 1464 1.1.1.1

Linux / macOS Terminal

ping -M do -s 1464 1.1.1.1

Authoritative Standards & Scientific Documentation:

Internet Engineering Task Force (IETF)

RFC 1191: Path MTU Discovery (PMTUD Specification)

Formal specification for determining maximum packet size avoiding router fragmentation.

IETF Networking Group

RFC 8290: The FQ-CoDel Hybrid Packet Scheduler and Active Queue Management

Definitive smart queue management standard eliminating latency spikes under saturation.

Frequently Asked Technical Questions

Why do some tutorials erroneously suggest MTU 1472 on PS5?

Because they confuse the ping payload test (1500 - 28 = 1472) with the interface MTU. Interface MTU is 1500 on DHCP and 1492 on PPPoE.