ouroboros/doc/man, branch 0.18.4

build: Remove raptor IPCP

2021-03-28T10:46:05+00:00

This removes the raptor IPCP. The code hasn't been updated for a while, and wouldn't compile. Raptor served its purpose as a PoC for Ouroboros-over-Ethernet-Layer-1, but giving the extreme niche hardware needed to run it, it's not worth maintaining this anymore. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

build: Update email addresses

2021-01-03T10:57:05+00:00

The ugent email addresses are shut down, updated to Ouroboros mail addresses. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

build: Update copyright to 2021

2021-01-03T10:56:28+00:00

Happy New Year, Ouroboros! Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ipcpd: Add congestion avoidance policies

2020-12-02T18:21:29+00:00

This adds congestion avoidance policies to the unicast IPCP. The default policy is a multi-bit explicit congestion avoidance algorithm based on data-center TCP congestion avoidance (DCTCP) to relay information about the maximum queue depth that packets experienced to the receiver. There's also a "nop" policy to disable congestion avoidance for testing and benchmarking purposes. The (initial) API for congestion avoidance policies is: void * (* ctx_create)(void); void (* ctx_destroy)(void * ctx); These calls create / and or destroy a context for congestion control for a specific flow. Thread-safety of the context is the responsability of the flow allocator (operations on the ctx should be performed under a lock). ca_wnd_t (* ctx_update_snd)(void * ctx, size_t len); This is the sender call to update the context, and should be called for every packet that is sent on the flow. The len parameter in this API is the packet length, which allows calculating the bandwidth. It returns an opaque union type that is used for the call to check/wait if the congestion window is open or closed (and allowing to release locks before waiting). bool (* ctx_update_rcv)(void * ctx, size_t len, uint8_t ecn, uint16_t * ece); This is the call to update the flow congestion context on the receiver side. It should be called for every received packet. It gets the ecn value from the packet and its length, and returns the ECE (explicit congestion experienced) value to be sent to the sender in case of congestion. The boolean returned signals whether or not a congestion update needs to be sent. void (* ctx_update_ece)(void * ctx, uint16_t ece); This is the call for the sending side top update the context when it receives an ECE update from the receiver. void (* wnd_wait)(ca_wnd_t wnd); This is a (blocking) call that waits for the congestion window to clear. It should be stateless (to avoid waiting under locks). This may change later on if passing the context is needed for different algorithms. uint8_t (* calc_ecn)(int fd, size_t len); This is the call that intermediate IPCPs(routers) should use to update the ECN field on passing packets. The multi-bit ECN policy bases the value for the ECN field on the depth of the rbuff queue packets will be sent on. I created another call to grab the queue depth as fccntl is write-locking the application. We can further optimize this to avoid most locking on the rbuff. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Allow pure acknowledgment packets in FRCT

2020-06-06T16:29:14+00:00

This adds the logic to send a pure acknowledgment packet without any data to send. This needed the event filter for the fqueue, as these non-data packets should not trigger application PKT events. The default timeout is now 10ms, until we have FRCP tuning as part of fccntl. Karn's algorithm seems to be very unstable with low (sub-ms) RTT estimates. Doubling RTO (every RTO) seems still too slow to prevent rtx storms when the measured rtt suddenly spikes several orders of magnitude. Just assuming the ACK'd packet is the last one transmitted seems to be a lot more stable. It can lead to temporary underestimation, but this is not a throughput-killer in FRCP. Changes most time units to nanoseconds for faster computation. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

doc: Add missing ecmp option

2020-05-01T12:37:32+00:00

The equal-cost multipath option wasn't mentioned in the Ouroboros man page. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Return number of written bytes on flow_write

2020-03-15T13:30:58+00:00

This is more in line with the write() system call and prepares for partial writes. Partial writes are disabled by default (and not yet implemented). Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

lib: Change return type of fevent to ssize_t

2020-03-15T13:26:49+00:00

The return type was still an int, but since it returns the number of events, it should be an ssize_t. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

irm: Revise naming API

2020-03-15T13:20:38+00:00

This revises the naming API to treat names (or reg_name in the source) as first-class citizens of the architecture. This is more in line with the way they are described in the article. Operations have been added to create/destroy names independently of registering. This was previously done only as part of register, and there was no way to delete a name from the IRMd. The create call now allows specifying a policy for load-balancing incoming flows for a name. The default is the new round-robin load-balancer, the previous behaviour is still available as a spillover load-balancer. The register calls will still create a name if it doesn't exist, with the default round-robin load-balancer. The tools now have a "name" section, so the format is now irm name ... Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders

ouroboros: Rename service to ouroboros

2020-03-14T14:39:07+00:00

The service was called "irmd", but it makes a bit more sense to give it the system name. Only the service name is changed, the irmd binary remains irmd. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders