Initial commit for TCP ROCCET source code.

README.md

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+# TCP ROCCET :rocket: (RTT Oriented CUBIC Congestion control ExTension)
+
+TCP ROCCET is a new TCP congestion control
+algorithm suited for current cellular 5G NR beyond networks.
+It extends the kernel default congestion control CUBIC
+and improves its performance, and additionally solves
+unwanted side effects of CUBIC’s implementation.
+ROCCET uses its own Slow Start, called LAUNCH, where loss
+is not considered as a congestion event.
+The congestion avoidance phase, called ORBITER, uses 
+CUBIC's window growth function and adds, based on RTT
+and ACK rate, congestion events.
+
+NOTE: A paper for TCP ROCCET is currently under review.
+ 
+The oldest Linux kernel version we tested with ROCCET is 6.1.
+
+## Setup
+
+* Debian: `sudo apt install linux-headers-generic`
+* Fedora: `sudo dnf install kernel-devel`
+(`sudo reboot`)
+
+## Build 
+`make`
+
+
+## Loading & Unloading the Module  
+**1.** Insert into Kernel: `sudo insmod tcp_roccet.ko`
+In case you get the "Invalid module Format" error, it can help reinstalling the kernel-headers.
+
+**2.** Use the Algorithm:
+* Either via globally loading it: `sudo sysctl net.ipv4.tcp_congestion_control=roccet`
+* Or via using it in specific measurements: `sudo iperf3 -c <Server-IP> -C roccet`
+
+**3.** Unload the Module: `sudo rmmod tcp_roccet`
+
+
+## Debugging (Using kprobe)
+In order to debug the `tcp_roccet` congestion control algorithm, there exists a Kprobe module (`roccet_kprobe.c`). Using this it is possible to inspect events generated by the algorithm. 
+
+In order to use the Kprobe module the following steps are necessary: 
+
+**1. Specify the event to inspect**
+For this head into the `tcp_roccet.c` source code and find the function the Kprobe should attach to. 
+
+For Example: 
+```
+__bpf_kfunc static void roccettcp_cong_avoid(struct sock *sk, u32 ack, u32 acked);
+```
+Specify this function name in the field `symbol_name` of the `kprobe` struct in `roccet_kprobe.c` 
+
+Obtain the arguments in the kprobe using the `regs` field. 
+(See the System V ABI for Linux under https://en.wikipedia.org/wiki/X86_calling_conventions#List_of_x86_calling_conventions)
+
+**2. Build Kprobe module**
+Use the provided Makefile to build the `roccet_kprobe.c` module for the local machine. (`make`)
+
+For this the adequate linux-headers are required 
+* Debian: `sudo apt install linux-headers-generic`
+* Fedora: `sudo dnf install kernel-devel`
+
+Required files for this are: 
+* `Makefile` 
+* `roccet_kprobe.c`
+* `tcp_roccet.h`
+* `tcp_roccet.c` (Optional; Need to remove corresponding entry in Makefile if missing)
+
+**3. Load Kprobe module**
+To then load the Module use 
+`sudo insmod roccet_kprobe.ko` 
+If you are seeing the error "Unknown symbol in module" you need to first load the roccet algorithm.  
+
+**4. See the trace output**
+To see the trace output use
+`sudo cat /sys/kernel/tracing/trace_pipe`
+
+**5. Unload Kprobe module**
+To remove the module again use 
+`sudo rmmod roccet_kprobe` 
+
+_See more info at_ https://docs.kernel.org/trace/kprobes.html and https://www.kernel.org/doc/Documentation/trace/kprobetrace.rst
+
+## Further Info
+* On TCP-CC Ops: 
+    * https://www.yonch.com/tech/linux-tcp-congestion-control-internals
+    * https://docs.ebpf.io/linux/program-type/BPF_PROG_TYPE_STRUCT_OPS/tcp_congestion_ops/
+
+# Setup Development Environment 
+For specific Kernel:  
+1. Download linux source (the version you want to develop for)
+2. Create Config via `make defconfig`
+3. Compile kernel via `make`
+4. Generate clangd Config via `python scripts/clang-tools/gen_compile_commands.py`
+5. Copy `compile_commands.json` to development directory  
+