In this tutorial I will provide a short example on how to use CSMA/ECA methods in the EdcaTxopN and DcfManager NS-3 classes. Changing the settings will provide different configurations of CSMA/ECA. Setting a deterministic backoff after a successful transmissions (Basic CSMA/ECA) In
CSMA/ECA, Channel errors, Schedule Reset and NS-3
In this attempt we implemented some kind of channel-induced errors. Ok, I know, it is not that specific, but the thing is that there are situations in which the Ack Timeout is reached, and most of the time it is
Implementing Fair Share aggregation for CSMA/ECA in NS-3
The final step towards completing CSMA/ECA proposal in NS-3 is to implement frame aggregation via the Fair Share mechanism. The slight difference with the previous post is that MAC events are handled with EdcaTxopN class instead of DcaTxop. The main reason is that aggregation
Changing DCF’s backoff mechanism in NS-3
Network Simulator 3 (NS3) is a discrete event-based simulator for many types of network technologies. Ranging from CSMA to LTE and SDN networks, you can practically ensamble together many pre-written modules from each technology until you get what you want.
Effect of stickiness in the throughput
Stickiness helps maintain a collision-free schedule once it is reached. Higher levels of stickiness prolong the collision-free state on the network because increases the resilience of the nodes when faced with channel errors. Nevertheless, when this number is too high (1000 for instance),
Combating channel errors with stickiness
We are trying to reveal the effect channel errors have on the throughput and in the construction of a collision-free schedule with CSMA/ECAqos. What we know We know that by not resetting the backoff stage after a successful transmission we implement Hysteresis
Reducing the collision-free schedule’s length in CSMA/ECA Part III
Just by attempting to halve the schedule length seems to be insufficient to meet DCF’s performance. In order to circumvent this issue, I propose a little more drastic approach towards the schedule reduction in CSMA/ECA. In this case, we are going
Reducing the collision-free schedule’s length in CSMA/ECA Part II
Collisions force CSMA/ECA+Hysteresis nodes to larger deterministic backoffs, increasing the number of free slots between successful transmissions and degrading the throughput when compared with DCF. This is leveraged by Fair Share, which makes nodes at backoff stage k transmit 2^k
Reducing the collision-free schedule’s length in CSMA/ECA Part I
One of the jewels of CSMA/ECA is its ability to build collision-free schedules with many nodes. The mechanism we came up with is called Hysteresis. It just instructs nodes not to reset their backoff stage, k∈[0,m], after a successful transmission. This results
Traffic differentiation with CSMA/ECA [Part 4]
There are other ways EDCA can provide priority at the MAC level [1, 1.5, 2, 3]. The Arbitration Inter-frame Space (AIFS) is a new waiting period for every Access Category (AC). ACs in a station should have a period equal to AIFS[AC] =