LTE 4G MTU WAN Packet Overhead/ SQM

SQM-QoS has recommendations for the link layer adoption for ATM and Ethernet connections, but what should I use for a 4G LTE service?

From what I have read the MTU is somewhat based on load of the network is there a tool to update the MTU periodically for a 3g/4g/5g connection?.

I have done some ping tests in windows and I seem to get fragmentation at and MTU above 1472 does that mean my MTU is 1500 as there is an overhead of 28 with ICMP pings?

C:\Users\Profe>ping 8.8.4.4 -f -l 1492

Pinging 8.8.4.4 with 1492 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.

Ping statistics for 8.8.4.4:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

C:\Users\Profe>ping 8.8.4.4 -f -l 1472

Pinging 8.8.4.4 with 1300 bytes of data:
Reply from 8.8.4.4: bytes=68 (sent 14672 time=81ms TTL=114
Reply from 8.8.4.4: bytes=68 (sent 1472) time=82ms TTL=114
Reply from 8.8.4.4: bytes=68 (sent  1472) time=82ms TTL=114
Reply from 8.8.4.4: bytes=68 (sent 1472) time=87ms TTL=114

Ping statistics for 8.8.4.4:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 81ms, Maximum = 87ms, Average = 83ms

similarly, I wonder on the ingress and egress speeds as it is muchly dependent on weather load etc...is there tools to periodically update them?

Have a look at:

for adaptive cake. Regarding overhead for lte, I am not 100% sure (but the if-in-doubt recommendation of 44 bytes will likely work), but with cake-autorate that does not matter much.

It is not about MTU, under load mobile tower will chop you off 1.2Mbps timeslots to have more or less balance between customers and fit into tower uplink.

reference please.

I think this might be too specific and too vague at the same time; cellular network implementations become mind bendingly complicated pretty quickly - see e.g.:

https://helpfiles.keysight.com/csg/89600B/Webhelp/Subsystems/lte/content/lte_overview.htm

And so I think it is not easy and potentially misleading to be so specific (in this case 1.2Mbps timeslots) and to make a reasonable generalisation (in this case chopping off into timeslots to spread out load between users).

I think it is safe to state that the bandwidth a 4G user experiences is variable and dependent upon a number of factors like signal quality, network operator restrictions and the load on the connected cell tower.


As @moeller0 points out @professor_jonny, cake-autorate:

has been designed for exactly situations like this. It certainly works well on my own 4G connection and we have lots of positive reports and data showing its efficacy from other users accumulated over the last few years.

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