cozybit / wmediumd

mac80211_hwsim modifications and related stuff
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Is there any polling mechanism in wmediumd.c ? #9

Open zijinchen opened 5 years ago

zijinchen commented 5 years ago

Hello, I have checked your wmediumd.c file and found the CSMA code, but I did not find the polling code, I wonder if there is any?Thank you very much!

bcopeland commented 5 years ago

On Mon, Sep 16, 2019 at 07:49:19PM -0700, zijinchen wrote:

Hello, I have checked your wmediumd.c file and found the CSMA code, but I did not find the polling code, I wonder if there is any?Thank you very much!

I'm not sure what you mean, can you expound a bit? Polling what?

zijinchen commented 5 years ago

The polling I mentioned refers to one of the two channel Access methods in 802.11 standard, one is DCF(Distributed Coordination Function), which corresponds to CSMA(Carrier Sense Multiple Access with Collision Avoidance), and the other is PCF(Point Coordination Function), which corresponds to the polling. Polling simply means that each node is asked whether data is sent, if it is sent, it is sent, and if not, it is asked about the next node

------------------ 原始邮件 ------------------ 发件人: "Bob Copeland"notifications@github.com; 发送时间: 2019年9月19日(星期四) 上午9:43 收件人: "cozybit/wmediumd"wmediumd@noreply.github.com; 抄送: "陈子晋"994173107@qq.com;"Author"author@noreply.github.com; 主题: Re: [cozybit/wmediumd] Is there any polling mechanism in wmediumd.c ? (#9)

On Mon, Sep 16, 2019 at 07:49:19PM -0700, zijinchen wrote:

Hello, I have checked your wmediumd.c file and found the CSMA code, but I did not find the polling code, I wonder if there is any?Thank you very much!

I'm not sure what you mean, can you expound a bit? Polling what?

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bcopeland commented 5 years ago

Oh, yes, there's no PCF implementation.

On Wed, Sep 18, 2019 at 07:04:31PM -0700, zijinchen wrote:

The polling I mentioned refers to one of the two channel Access methods in 802.11 standard, one is DCF(Distributed Coordination Function), which corresponds to CSMA(Carrier Sense Multiple Access with Collision Avoidance), and the other is PCF(Point Coordination Function), which corresponds to the polling. Polling simply means that each node is asked whether data is sent, if it is sent, it is sent, and if not, it is asked about the next node

zijinchen commented 5 years ago

In my humble opinion, PCF should be easier to implement in principle than DCF.What's the reason there isn't? Is it because it's inefficient?Or is there a reason it can't be done?Thank you very much!

------------------ 原始邮件 ------------------ 发件人: "Bob Copeland"notifications@github.com; 发送时间: 2019年9月19日(星期四) 上午10:14 收件人: "cozybit/wmediumd"wmediumd@noreply.github.com; 抄送: "陈子晋"994173107@qq.com;"Author"author@noreply.github.com; 主题: Re: [cozybit/wmediumd] Is there any polling mechanism in wmediumd.c ? (#9)

Oh, yes, there's no PCF implementation.

On Wed, Sep 18, 2019 at 07:04:31PM -0700, zijinchen wrote:

The polling I mentioned refers to one of the two channel Access methods in 802.11 standard, one is DCF(Distributed Coordination Function), which corresponds to CSMA(Carrier Sense Multiple Access with Collision Avoidance), and the other is PCF(Point Coordination Function), which corresponds to the polling. Polling simply means that each node is asked whether data is sent, if it is sent, it is sent, and if not, it is asked about the next node

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bcopeland commented 5 years ago

Mainly because I've never seen a deployed system that uses it. I would take a patch that implements it as an optional simluation though.

On Wed, Sep 18, 2019 at 07:19:06PM -0700, zijinchen wrote:

In my humble opinion, PCF should be easier to implement in principle than DCF.What's the reason there isn't? Is it because it's inefficient?Or is there a reason it can't be done?Thank you very much!

zijinchen commented 5 years ago

As far as I know, the efficiency of PCF is higher than that of DCF when a large amount of data is transmitted, so it is of certain practical value. Looking forward to your early update, thank you very much!

------------------ 原始邮件 ------------------ 发件人: "Bob Copeland"notifications@github.com; 发送时间: 2019年9月19日(星期四) 上午10:29 收件人: "cozybit/wmediumd"wmediumd@noreply.github.com; 抄送: "陈子晋"994173107@qq.com;"Author"author@noreply.github.com; 主题: Re: [cozybit/wmediumd] Is there any polling mechanism in wmediumd.c ? (#9)

Mainly because I've never seen a deployed system that uses it. I would take a patch that implements it as an optional simluation though.

On Wed, Sep 18, 2019 at 07:19:06PM -0700, zijinchen wrote:

In my humble opinion, PCF should be easier to implement in principle than DCF.What's the reason there isn't? Is it because it's inefficient?Or is there a reason it can't be done?Thank you very much!

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.