How to reduce high network accessing time? - networking

What we have
My office network have a new 20mbps dial-up connection. The internet is connected to DLINK 600-L Wifi Router. An LAN port of router is connected to DLINK's gigabyte switch that connects all the PCs in the building. We do have a good traffic in internal network due to the office software activities. Before this new internet connection, we used static IP routing in another router. But now it is using DHCP.
My problem
When we connect to wifi and browse, we are getting only 1mbps to 2mbps instead of 20mbps. Also often the download is broken and fails in middle.
Test I have tried
Opened 2 terminals.
Started a ping to router in terminal 1.
ping 192.168.0.1
Started a download in terminal 2.
wget http://www.dlink.com/-/media/Consumer_Products/DIR/DIR%20600L/Manual/dir600L_manual_100.pdf
Result: The ping was 5ms - 10ms when started. But as the download started at 512kbps - 2mbps, the ping started to rise up to 10000ms and the download speed went down gradually to zero. Thus download failed.

You're suffering from Bufferbloat. In short, some router uses too much buffering under load, which causes extremely high latencies.
The solution would be to replace the DLINK with a debloated router (I recommend a recent version of OpenWRT with fq_codel), and set up traffic shaping to ensure that the congestion happens on that particular router.

Related

Forward wake on lan using zerotier

I have a linux computer (super small low powered, similar to raspberry pi) that is running zerotier. I can ping this from the outside and this computer has access to an internal server. What I am trying to do is to send wake on lan packets to the zerotier computer and have this forward the packet to 192.168.1.5.
The purpose of this is that the server is also running zerotier and I can access it from the outside, but when the server is shut down there is no way to reach it from the outside. I am therefore trying to use this linux computer to forward the wake on lan packets so that I can boot the server remotely.
For my case it would be enough to simply ssh into the linux computer and send the wake on lan from there, but sometimes my wife need to boot the server and I doubt I can teach her any time soon how to ssh into the linux computer and send a WoL from command line. Therefore I need the linux computer to forward the wake on lan to the internal ip. How can I do this?

How find correct Ip for connection Client/Server Qt?

I created two Qt apps: one client and one server.
I use them to send some data for handle a remote device.
If I am in localhost I haven't issues about them, but when i search to connect them by internet i don't know how to find correct Ip server to connect Socket Client.
How i can find this ip node?
Is there a class to find It?
you cannot find it automatically, if this is what you're asking about.
In real life you would deploy your server on some publicly accessible host, give it a domain name (important part as your host can change the IP address at any time) and connect the client via the DNS domain.
However if you're just playing around and you want to show to the world that your app works, specifying the IP address of the server in your client code would be perfectly fine (assuming you're running both the server and the client in the same network).
In that case, if you're running mac/linux run the command ifconfig (or just ip depending on the distribution). On Windows you can run the command ipconfig. Both windows and linux will give you a similar output resembling this:
Pay attention to the network adapters. There can potentially be many of them. You may have some emulated adapters if you have docker or VMWare, you may have the wireless adapters if you have a WiFi card, and then the ethernet adapters if your computer can connect to the the internet with an ethernet cable. Each of these adapters specifies a different IPv4 address. You want to pick the one that is connected to the same network as your client. So for instance if both your server machine and your client running machine are connected to the same wifi, you pick the address from the Wireless LAN adapter

Unable to load localhost on web browser in Raspberry pi

I created a web server on my Raspberry pi using Apache2 and Wordpress. At the beggining I used a local network (IP is 192.168.1.103) and then used a Huawei dongle to connect to the internet. When the dongle is connected, web browser unable to load localhost. When dongle is used it shows that:
"The website at https://192.168.1.103/ seems to be unavailable"
How do I correct this error?
The IP address you're using to connect to the site is a local network address.
When the device is using a mobile data dongle it's no longer connected to your local network so the local IP no longer works.
You could find out your IP address when the dongle is connected however that's impractical. There's a good chance each time you reconnect the IP address will change. Your server needs to have a static IP address.
You cannot directly access a device on a Local network/LAN from the outside/WAN. Notice you are trying to connect to your localhost so you need to be directly connected to the device in question or through a medium which intenrally connects the devices together, such as a router/wifi hub.
When we break your steps down; you are trying to connect to a localhost/device on your LAN but you are connecting via dongle which is actually connecting via outside/WAN connection. This means your GET request for the localhost URL is going to the ISP/dongle providers server first then trying to get back into your LAN - this is not possible, hence the error.
Fix: Connect to device directly or via a medium such as a router (through ethernet or wi-fi).
Additionally: if you wish to type in a url instead of an IP then this will need to be resolved. This is done by manually typing in an entry in your hosts file (in the Raspberry Pi) and inputting the resoloution info i.e www.yourwebsitename.co.uk and local IP i.e. 127.0.0.1.
Your webserver (i.e. Apache) may need to be restarted for changes to take effect. If site is not loading correctly then it could be that your web browser is displaying a cached image in which case simply clear cache in your web broswer and reopen.

2Wire router port forwarding

I am having some trouble allowing my 2wire router (provided by AT&T to forward certain ports.
I have a raspberry pi running subsonic (a music server) and I would like to access it from the outside internet. I have configured the pi with a static LAN IP address and have opened the specified ports (4040 and 80) on both TCP and UDP. I have also confirmed the service is active and is listening on the specified ports via netstat.
When I attempt to connect, however, from my WAN IP I am confronted with a connection refused dialog. Checking the firewall logs on my router, I see this message
IN=br1 MAC=--:--:--:--:--:-- SRC=(my computer IP) DST=(My WAN IP) LEN=40 TTL=240 PROTO=TCP DPT=5060 Unknown inbound session stopped
It appears that my firewall is still blocking the external connection. What strikes me as odd is, although I am unable to connect I can still see that the port is open from an outside port scanner. Using the service provided from http://www.yougetsignal.com/tools/open-ports/ I have confirmed that my IP has port 4040 to be open.
Once again, I have confirmed that the service is indeed listening on the raspberry pi, setup a static LAN address and created the protocol for both TCP and UDP....
Any help on this matter would be greatly appreciated.
Thanks in advance!
Ok so for whatever reason it was working all along. Apparently it was just getting confused by me trying to connect to my own router. I confirmed this by connecting to the server via 4G on my phone.
Dumb mistake by me.

IOS4 - Send data using UDP socket on Wifi

I am trying to send data using the AsyncUDPSocket class. And I can send data using the iPhone simulator over the wire to another machine that is running a simple C-coded listening server. I can also receive data over the wire using a client connected to the simulator(server). However, when I tried the same over Wifi, using the simulator, I could only send data but not receive any data.
I read on another post, that unicast data makes this possible. How can I acheive this using AsyncUDPSocket?
Thanks,
Angelo.
Ok, I figured this out. A newbie kind of thing, really.
When I set my Mac network preferences to Ethernet, I get an IP for me to communicate. However, when I turn Airport(Wi-Fi for more newbies) ON, and ethernet cable disconnected, I checked my network preferences, and sure enough my IP address was a different one.
Spoke to a friend (an ace in networking) and the thing clicked immediately: On WiFi networks a DHCP server allocates an IP address. This IP address has to be reserved, at the very least, at the DHCP server. Since my IP was not reserved, I had to change the IP address, in my udp_client.c file, recompile and run the client to connect.
BTW, I can now communicate between my iPhone and my PC using my local WiFi (office) network.
For any who might face the same problem, do not be assured that the IP address of your mchine is the same, when you switch from LAN to Wifi, and use the device mostly for WiFi reated testing. :)

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