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Messages - Remote_Mike

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1
General discussion forum / RRC-1258 Control DHCP on
« on: 2016-01-10, 17:32:31 »
Hi there!
If I am switching on the DHCP at RRC1258 Control then I will get a IP address from my local router.
Unless I don't find out the IP address given by my router I cannot access the RRC1258 Control.
Is there a given URL name that makes it possible to access easily to my RRC1258 Control without knowing the given IP address?

Thanks in advance
Mike

2
Hi Jan

I quite agree with you.

Mike


3
To be more precisely:
When a TCP/IP connection is established the client side of the connection uses a port number.  Unless a client program explicitly requests a specific port number, the port number used is an ephemeral port number.  Ephemeral ports are temporary ports assigned by a machine's IP stack, and are assigned from a designated range of ports for this purpose. When the connection terminates, the ephemeral port is available for reuse, although most IP stacks won't reuse that port number until the entire pool of ephemeral ports have been used.  So, if the client program reconnects, it will be assigned a different ephemeral port number for its side of the new connection.


All-in-one "home" modems/routers are ready to use for average costumers/users without deep knowledge of Ethernet technology. Software/hardware developers are forced to deal with various needs and requierments unless they develop their stuff for certain applications with skilled and trained users. I guess a professional router with firewall or DMZ would provide a more appropriate setting of DoS attack protection.

@Mark, HB9AZT
I knew that I'm not the only user with these kind of problems ...  ;)

Mike

4
This behaviour of incrementing port numbers is called "ephemeral port".
When the connection terminates, the ephemeral port is available for reuse, although most IP stacks won't reuse that port number until the entire pool of ephemeral ports have been used.  So, if the client program reconnects, it will be assigned a different ephemeral port number for its side of the new connection.
Look for the words "ephemeral port" on the internet and you will find the explanation.

Mike

5
Hi Jan

The reaction of my router makes absolutely sense to me.
As described in several documents concerning the DoS attack the TCP and UDP based packet flooding attack tools sometimes alter source and/or destination port numbers to make reacting with packet filtering by service more difficult [e.g. "Trends in Denial of Service Attack Technology"].

At my point of view nowadays state of the art routers have to block increasing source port numbers unless this function is disabled. My new router has the option to disable the DoS firewall. Maybe a short statement in the RC-1216 user manual would make sense to point that out.

Mike

6
Hi!

Finally I've found the problem!
The SteppIR webpage tries to send continuously some Ethernet packets to the remote webserver of the RC-1216H.
For some reasons the sending source port will be incremented for every packet.
Modern routers have a port scanning blocker (so called DoS protection). Unfortunately my remote router misinterprets the continuous flow of incrementing source port IP-packets as a DoS attack and blocked the traffic after a certain time. I had to disable the DoS protection of my remote router.
I couldn't use the SteppIR remote rig if If I hadn't analyzed the problem by myself with Wireshark. Unfortunately I cannot find any words about disabling DoS or similar statement in any user manual.

Kind regards
Mike

7
Hi Jan

Thanks a lot for your support. I appreciate it very much!
Now it's a little bit better and my webpages get not blocked so often but I have still some trouble.
If I pinging my remote site (to my remote ADLS Modem) than I will get a reply time of about 33ms (with 32bytes packets). That seems to me pretty quick. Furthermore I have a continous data stream without timeouts even with larger ping packets (1000 bytes).

But as soon as I start the RC1216H (for SteppIR controlling) or the Webswitch 1216H (for Rotor controlling) after a certain time I get timeouts and the webpages of the RC1216H or Webswitch get disconnected and my ADSL router will be blocked. The ping time increases dramatically to >500ms per ping or I get even timeouts.
The data normally sent by RC1216H are just a few bytes (20 bytes to about 500 bytes per frame).

I just wondering if the latency times of the webservers of the RC1216H (or the Webswitch) are short enough to respond to the ACK- and SYN-packets? Respectively I am wondering if the refresh time (Timeouts) specified in the Java scripts are still to short.

Unfortunately I get also lots of TCP checksum errors if I am tracking the Ethernet packets with Wireshark. Formerly I disabled the TCP offload in the network settings and therefore I couldn't see the errors. Maybe this information helps.

Somtehing is still strange with the webservers and I would be very happy if we could solve my problem.

Thanks in advance.

Kind regards
Mike


8
Configuration, RRC 1258 / Strange behaviour
« on: 2013-04-03, 09:53:11 »
Hi there!
Thanks Mitch for your offer.
In the meantime I have found the problem. It has nothing to do with the network settings (IP, DHCP, NAT, DMZ, etc.).
Unfortunatley the "Audio Dual-RX" switch was set to "YES"! That doubles the bandwidth and caused the network problem due to limited bandwidth.
This cost me a lot of nerves..  ;)

Mike

9
Configuration, Webswitch 1216H / RC-1216H Webpage connection
« on: 2013-04-03, 09:45:19 »
Dear Jan

Beside the RC1216H and Webswitch 1216H I am using the RRC-1258MkIIs which works pretty well.
I am loosing the connection to the RC1216H and Webswitch even when nothing other is on duty (no Ethernet traffic) on my remote site. That means the ADLS modem/router is in idle mode (1500kbps down/150kbps up).

I am under the impression that the Java-Script called by the RC1216H webpage produces some traffic jam due to timeouts. The Java Script calls a recursive function with timer settings (500ms, 1000ms). Could these timer settings (or timeout settings) cause the traffic jam and blocks my remote site router?
I do understand that the webpage caller (Source) sends every second a status request to the RC1216 (Destination) and counts up therefore the port number (Source port). But is it really necessary to do so every second for live status requests?

Thank you for your reply!

Kind regards
Mike




10
Configuration, Webswitch 1216H / RC-1216H Webpage connection
« on: 2013-03-29, 23:51:56 »
Hi
I am using the RC-1216H for controlling the SteppIR antenna via the SteppIR controller (DATA IN/DATA OUT interface).
If I am opening my webbrowser (IE or Google Chroma) I can access the webpage of the RC-1216H. But after a while (about 15 secs or so) the green Online LED on the webpage stops blinking and restars after a while. It seems that the RC-1216H looses the connection to my browser or the 1216H Webserver hangs up. How can that be???

Even with the WebSwitch 1216H I have the same problem. After I have connected the Webserver of the WebSwitch I am loosing the remote connection and I have to restart (reload or open the webpage again) the webpage.

It is really annyoing and I don't have any idea to solve that problem.
Thanks for your  help!
Mike

11
Configuration, RRC 1258 / Strange behaviour
« on: 2013-03-09, 13:46:35 »
Hello!
I managed to configure the Radio and Remote RRC-1258MkII and it works on my local network.
The Control RRC finds the Radio RRC and I can connect to the Radio RRC.

If I place the Radio RRC to my remote station at my shacks place something goes wrong.
I test my RRC equipment with LogMeIn remote login.
If I connect to the Radio RRC the yellow LED on the Radio RRC (AUX/MIC) goes on (SIP connection OK) and the LEDs on my Ethernet switch and Radio RRC (green Ethernet LED) are flashing (means Ethernet pakets are transfering from ADSL Modem to the switch and to the Radio RRC) .

BUT just a few seconds later the ADLS router on the remote site will be blocked and I cannot access to the Ethernet.
If i try to start the Internet browser I will not get a connection to the Internet. If i check the status of the Radio RRC it seems to be ok (no errors) although the Ethernet is blocked.
The Ethernet connection to the ISP will be blocked and sometimes I get even a new IP address from my ISP.
That means to me that the ADLS router hangs up and at startup I will get a new IP address from my ISP.

Is it normal that the Ethernet LEDs (green) on the Control and Radio RRC blinks quickly?
And I have seen on the Radio RRC that the Audio IN and OUT Ports and the Command IN and OUT ports are not the same. When I try my RRC set up at local network at home the IN/OUT ports for Audio and Command are the same (11000, 12000). 
I am using the ports 11000, 12000, 5070 for the connections.
A remote access to the Radio RRC webpage is possible. That means the IP address of Radio RRC is sent to the dynamic DNS.
The Radio RRC is in the DMZ of the ADLS-Router with a fix IP address. I tried to do a port forwarding with port 11000, 12000 and 5070 but the result was the same (as mentioned above).
I try to do the setup without connected radio (Elecraft K3) to be sure that only the RRC could be the problem.

All other remote rig is working perfectly well (rotor, SteppIR antenna).

Please could anybody help me? I have not the faintest idea what the problem could be! And I already wasted a lot of time to manage the problem without results.

Thanks a lot
Mike






12
A real monoflop doesn't bouncing like a mechanical relay does.
And if the relays are switched on/off (in terms of monoflop function) the output signal is bouncing because of the mechanical contacts.
The K3 can be switched off by sending a "power off" -command via serial port. But the K3 cannot be switched on via serial port. The K3 needs a small pull down at pin 8 (ACC connector) for remote switching on. This pull down signal must not last for ever it is just a small pull down signal of several milliseconds.
For that reason I trigger a monoflop (NE555) via the relays and the monoflop turns on the K3 remotely (electrically isolated via optocoupler). For K3 power off I am using the power off command via serial port.

Mike

13
Unfortunately the 1216H doesn't support real monoflop functionality. Forget about the HTML commands for this function. Use a real monoflop as NE555 or similar and switch on/off a relay for triggering the NE555.
I am using a K3 and this TRX needs a kind of impulse for startup.


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