Hi,
I am trying to increase tftp firmware download speeds to the modem.
Does the tftp download speeds depend on Class of Service, upstream Max, Downstream Max provided to modem or is the tftp download speed a separate from it? So far I see the following constraints that could affect tftp speed.
1. Max download speed of particular modem.
2. Max download speed of TFTP server and connection.
3. Mas download speed of CMTS connection
4. Configuration of TFTP server.
5. Configuration of CMTS possibly?
6. Configuration File Settings. I am trying to rule this out now.
7. Network Collisions max speed.
Thanks
You can add a classifer/serviceflow to the CM config file which matches TFTP server IP. Then you can assign custom upload/download speeds to this traffic.
Otherwise the TFTP traffic will match your default service flows (the first listed upstream and downstream flows in your CM config file)
But even if your config file allows high speed, you will probably find the TFTP transfer is much slower than this. I believe it is a limitation of the protocol (small block size etc).
You can sometimes makes tweaks to the TFTP server and modem. For example the Arris modems allow you to alter the TFTP block size to try and get some more speed.
If you setup a classifier to match your TFTP traffic (eg match on TFTP server IP), you can steer this traffic into its own service flow, and apply whatever up/down speeds you like.
If you do not setup a service class, then the TFTP traffic will land in your "default flows". These are the first US and DS flows defined in the config file.
However as you have seen TFTP typically isn't very fast. This is due to factors such as the small block size for each chunk of data.
Some TFTP servers and modems let you tweak (increase) the block size to try and get a bit more speed.