"fixing" a BY cable modem :/

[suicidal_monkey]

recently I've been experiencing severe ping spiking. My ping will jump up to like 400-600 from its normal 30-60. I have a blueyonder 512k connection, and my server is running XPpro, as is my own pc. I've used netgraph and It's not caused by loss or choke. they both remain at or very near zero, but my ping continues to go mental. it's like the info is cache-ing somewhere and I'm getting the packets in bursts.

It's not server specific so its my connection to the web thats at fault.
It's not my housemate because I unplugged him and the pings were still going mental.
It's not other applications like kazaa because I turned all those off...

I seem to be able to rectify the problem sometimes by restarting my pc, the server and the modem most of the time, and my guess is its the cable modem somehow. I think blueball said something on the server about it but I cant remember what :roll:
Could be the server dying :/

[Anonymous]

The problem is due to the BY UBRs (Universal Broadband Routers) being unable to cope with the amount of traffic on each channel. Cable Modems can have up to 6 channels and you can choose which one you use from http://192.168.100.1/config.html and editing the box named "Upstream Channel ID". Interestingly, BY are not particularly good at load balancing and, in my area, everyone apart from a few people were on channel 3.

BEFORE YOU DO ANYTHING, write down the channel you are currently using so you can revert to it if all alse fails. I had been on channel 3 which was giving atrocious ping times. Channel 2 works great for me. Interestingly, to get channel 2 I had to enter channel 5 as my desired channel. To get back to 3 I had to enter 6. Don't know why but it seemed to reduce any number entered by 3 - go figure :-) Anyway, once you enter a number, click "SAVE CHANGES" and then "RESTART CABLE MODEM".

Carrying out the above actions got me from pings of over 250 to less than 50 :-) I started looking at this when I noticed the problem didn't exist during the day (i.e., not too much traffic). It would only start after about 4:30 or 5:00 pm. There is lots of talk in the BY newsgroups about this and a very good site at  http://homepage.ntlworld.com/robin.d.h.walker/ but it is not for the faint hearted.

Don't worry if some channels don't work or give equally poor results. Not all are enabled/available and some will be heavily loaded. Keep trying til you get one you like :-)

HTH?

[suicidal_monkey]

nice one
knew I'd seen that config page before.

I did find my ping restored itself almost to normal after I restarted the server pc though :/ But I will be giving it away soon. Then I just have to work out the best way to share the cable connection without a server. I was hoping to just be able to plug the modem into my hub along with the two pc's but I'm told I will need a router :? but then I read this:

The SURFboard cable modem can be used as a gateway to the Internet by a maximum of 32 users on a Local Area Network (LAN). When the Cable Modem is disconnected from the Internet, users on the LAN can be dynamically assigned IP Addresses by the Cable Modem DHCP Server. These addresses are assigned from an address pool which begins with 192.168.100.11 and ends with 192.168.100.42. Statically assigned IP addresses for other devices on the LAN should be chosen from outside of this range

now I'm confused

[OldBloke]

You don't need a router but it's the best solution.

You two main choices are a gateway PC or a router. You could use your own PC as a gateway but it would mean having it switched on at all times. You would need to have two nics installed in it. One connected to the Surfboard and one connected to a hub (for multiple access). Then any other PC can connect to the hub and by using ICS get to the web.

A router is a far better solution.

Connect the router to the surfboard, connect PCs or hubs to the router and there you go. This will normally allow up to 254 PCs to be connected.
My advice is to switch off DHCP in the router and give all PCs static IP addresses in the 192.168.X.X range. This will allow you to do any port forwarding necessary.

I've got the Linksys BFSR81 and I've had no problems with it.

HTH

[Anonymous]

I got the Linksys BEFSR41 (http://www.linksys.com/products/product.as...scid=29&prid=20) and similarly no probs (as long as you use latest firmware). You can also look at Netgear and SMC. Don't bother with any cheap no-name routers - believe me, more trouble than their worth. You should be able to get a decent solution for about £70 if you shop around. The two linksys models mentioned have built in switches. if you want to be a bit flashy then look at BEFVP41 which has good VPN support with IPSEC: http://www.linksys.com/products/product.as...cid=29&prid=411

[Stryker]

at last something interesting :-)

ur right, my BY cable modem was on channel 1, changed it to channel 2 and shaved around 10ms average off my pings to blackadder COOL.

[Anonymous]

Was that good enough to get the target removed from my back (or at least made smaller)?

[suicidal_monkey]

You two main choices are a gateway PC or a router.

Atm I use a gateway pc that sits in a cupboard in the hall but it'll probably be given away sometime in the next month or two.

The SURFboard cable modem can be used as a gateway to the Internet by a maximum of 32 users on a Local Area Network (LAN). This little bit of info off the modem page makes me think that the modem can handle the routing itself, albeit for only 32 ip's but then I only need 2 of them

I will keep the router offered in mind, though I also know a mate down the road from me who might be replacing his router with a wireless version *sigh* at about the time I might be giving my gateway pc away would be nice to have a switch in place of the current 10T hub, thats for sure.

[Stryker]

Was that good enough to get the target removed from my back (or at least made smaller)?

if I cut you down with a beautiful TK then at least you'll know it was a genuine accident :-)

[Anonymous]

You can only do this in 1 of 2 ways. Either Dual-home a PC to use as a gateway or use a router. The text on the cable modem pages is misleading. It means that there can be 32 clients behind the modem. Not 32 directly connected to it. This is probably a limitation of the DHCP server in the modem. The cable modem will only supply 1 IP address from your ISPs network therefore you cannot plug 32 PCs into it. You need to set up NAT for that. HTH?

The Following was lifted from http://www.rodmac.pwp.blueyonder.co.uk/FAQs.htm

==========================

Although you only get 1 IP Address with the Cable Modem, you can set up some sort of home network with as many computers as you want and all can access the Cable Modem.  You may need to get a Router to do this, or set up one computer as a server and have two network cards in it (one for the Cable Modem & one to connect to your hub or other computer .  Since only 1 IP Address is given out, only 1 Computer can be connected to the Cable Modem.  Any other Computers would need to be connected to this computer to access the Internet through the Cable Modem.  See the links page for sites that explain this in more detail, or visit the newsgroup news:blueyonder.self-help.networking.  

If you have more than one computer on a LAN at home, and you want to make the cable modem available to them all, you cannot just plug the cable modem into your LAN hub, because the cable modem will communicate with only one MAC address, and will issue only one IP number via DHCP. There are two possibilites:

1. Kit out one of your PCs with two ethernet cards, one which is on your LAN hub, and the other which is connected solely to the cable modem. Then turn on Microsoft Internet Connection Sharing, or another IP routing program, to enable your other PCs to communicate to the cable modem. The disadvantage of this approach is that the ICS/routing PC has to stay online all the time: if it crashes, or has to restart, the other PCs lose their connection.

2. Purchase a DSL/Cable Router, such as the Linksys BEFSR41. This is a dedicated device with one WAN port which connects to the cable modem, and four LAN ports available for PCs.

In both these cases, the router is the single device to which the cable modem issues the single IP number, and the other PCs communicate with the internet via a process of Network Address Translation (NAT) performed by the router. For connections initiated by the PCs (e.g. web browsing, e-mail, news), this process works almost infallibly. However, for connections initiated by remote computers trying to connect to you (some games, instant messengers, Napster, some real-time streaming protocols), there will be problems because the router receives the incoming call, but does not know to which PC to pass it (this problem applies even for games on the ICS machine itself). Hence the need for port forwarding. The router can be configured to recognise that incoming calls on a certain port should be passed to a nominated PC. The restriction is that only one local PC can respond to incoming calls on any given port. The advantage is that the NAT router becomes a simple firewall by default, because all incoming calls are dropped unless an explicit port-forward is configured.

[suicidal_monkey]

nice. thanks for clearing that one up. I guess I could make my pc the gateway as it is on most of the time :roll: or I might get one the routers I have been told are/might-be on offer

btw, someone mentioned turning DHCP off to asssign static ip's, I imagine for port-mapping and firewalls? I got around this in the XP firewall by mapping ports using the pc's network names instead of an actual ip. i.e. instead of 192.168.0.99 port 3078 I just added schnell port 3078 or server port 3078 seems to be working fine, although I guess it depends on the application...

p.s. I changed the network channel thing on the modem and my pings have gone back down to the 30-region rather than the 60-region I was using channel "4" before, and now I'm using channel "5"

[Anonymous]

Great stuff.

The port forwarding using names or IPs will depend on what your network/firewall supports. The linksys port forwards based on IP address.