wireless connection drops off at times

  dvdcllns 12:22 10 Mar 2010

We have installed a wireless network on a ship to allow crew access to the internet. Some details here: the harbour provides a WiFi access and the account we have allows for ten people to access the account at any one time through laptops etc.
Within the ship we have set up a wireless system comprised of a Buffalo Wireless-G Mimo Performance Ethernet Converter to receive the WiFi signal (good, large high gain arial attached), this is wired to a Netgear FVG318 802.11g VPN router. This in turn is connected to a 'Homeplug' circuit using Devolo wireless extenders which are sited about the ship. It obviously works and the configuration is correct for I am able to post this thread.
The problem is, at times, the access 'drops off' but Skype will stay available. Would it be too many people trying to access the net via the router at any one time? Can the router accept more that eight people using it at any one time, there are eight ports available for network cables? Rebooting the router fixes the problem but only for a short while.
Any ideas would be welcome.

  rizlo29 15:57 10 Mar 2010

Well if skype still works when this happens, you are still connected to the Internet.

Here's a couple of suggestions. It could be your firewall blocking port 81 every so often or more than likely its something to do with the domain name service.

Domain name service (dns) is a server which converts addresses we use such as 'yahoo.com' into the servers address so the computer can recognise the address. Computer communicate with ip address such as (dns) allows us to type in the address and it converts it for us.

If your computer is configured to assign you an dynamic IP address then it automatically assigns you to your isp's dns server. I'm thinking when so many computer connect to the router, it conflicts with the dns. Without dns functioning, you cant surf the web.

You could set up a static ip and use a open dns to stop the conflict. Before you do that, next time you have this problem do this.

start> run> type cmd and press enter. On the prompt screen type ping "yahoo.com" without the quotes but make sure there is a space between ping and yahoo.

If it ping that means you can connect to the yahoo server so the problem is with the dns server. If it doesn't ping then you cant connect and could be a firewall problem blocking http port 81. To confirm its port 81, when it happens again send an email as emails use a different port.

If you can send emails its definitely a prob with port 81. If you cant then its something more than just the firewall.

Hope this makes a tad of sense to you lol.


  dvdcllns 06:01 11 Mar 2010

Thanks for the response, I'll give it a try later today when it goes down, which it will.
One small problem though, how do I send an email if I can't access a mail account such as Yahoo?
Meanwhile I will try as much as you suggest as possible.

  mgmcc 12:16 11 Mar 2010

I think the suggestion was to use an email program, such as Outlook Express, Windows Mail, Thunderbird etc, where outgoing mail is via an SMTP server on port 25. If your mail is "web-based" and managed through a web browser, you're up against the same problem with port 81 connections.

  mgmcc 12:20 11 Mar 2010

Actually, it's Port 80 that is used by http connections, not 81.

  rizlo29 13:00 11 Mar 2010

Yes, thanks for clearing thinks up, mgmcc.

  dvdcllns 14:21 11 Mar 2010

Thanks for clearing that up, I'll get one of the guys who doesn't use a 'web based' mail like Yahoo to try it.
Meanwhile, I'm still waiting for the system to go down. Why today??

  dvdcllns 16:36 12 Mar 2010

A chap with Outlook Express on his laptop says he cannot send emails when we have the problem.
When we have the problem pinging yahoo.com fails.
The router settings are:
System Name: FVG318_NETGEAR
Firmware Version: v2.1.2-67R (this is the latest!)
MAC Address: 00:22:3f:50:93:34
IP Address:
DHCP: Enabled
IP Subnet Mask:

Wireless Status: Disabled (we use the devolo homeplug rather than the wireless offering)
Mode: g only
Security Settings: None
Region: Asia
Channel: 6
AP MAC Address: 00:22:3f:50:93:34

WAN State: UP
NAT: Enabled
Connection Type: DHCP
Connection State: Connected
IP Address:
Subnet Mask:
Primary DNS:
Secondary DNS:
MAC Address: 00:22:3f:50:93:35

I am offered the following in the WAN ISP setting page of the router:

Internet (IP) Address (Current IP Address) help Domain Name Server (DNS) Servers help

Get Dynamically from ISP (radio button)
Use Static IP Address (radio button)
IP Address: . . .

IP Subnet Mask: . . .

Gateway IP Address: . . .

Get Automatically from ISP (radio button)
Use These DNS Servers (radio button)
Primary DNS Server : . . .

Secondary DNS Server: . . .

Any further thoughts will be very welcome.
The above readings are a cut 'n paste will the system is working, hence this new info.
I am able to listen to a UK radio staion via Pure Lounge when the system is down, similar to the Skype access (we are in Denmark)
Many thanks in advance

  mgmcc 11:56 14 Mar 2010

Can you see if you can get similar settings for the router when the internet connection has failed? The details as shown above are fine while it is working.

  dvdcllns 15:06 14 Mar 2010

Hi mgmcc
These settings on the router are the same whether the link is up or down. These are the settings i see when I connect to the router from another machine be it by wireless or direct netork cable.
I was wondering whether I should use the static IP & DNS option and enter the addresses as shown.

Thanks for the reply.

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